Home

Accessible UIP client for Windows Phone 8

1. 3 0 6 Rendering the Ul The information about UI elements comes from the server in form of XML description This description is parsed into inner object representation classes shown in figure 4 After this is done InterfaceManager will call the Render method of the Renderer class This method will traverse the tree of the newly created instances of classes from figure 4 and for each one creates a new class instance which will wrap the platform native UI controls as described in the next section class UlElements mm ModelManager Control object FrameworkElement Render object void SetupGeneralProperties IRenderable void SetupPositionProperties void SetupProperties IRenderable void SetupTextStyles IRenderable TextStylable void UipBase IRenderable property Class string Position Position Figure 6 UipBase class diagram 3 0 7 Representing the Platform native UI Components There is one more step toward the controls that are rendered to the user which involves the transition from the inner object representation to the platform native components The platform native components will be wrapped into wrapper classes whose names will indicate the component which is wrapped inside i e UipPasswordBox will be the wrapper class of WP8 s PasswordBox There will be an abstract base class UipBase which will contain everything the wrapper classes have in common methods for binding to models and
2. HandlelfinterfaceRequest Model void property IsModelUpdate string bool Id string ModelManager ModelProperties Dictionary lt string ModelProperty gt WaitForModel string Task lt Model gt hm a modelReference property Models Dictionary lt string Model gt Property INotifyPropertyChanged ModelProperty z _modelReference Model readOnly InterfaceManager Interpolate void ModelProperty XElement Model rootPanelRef Panel readOnly OnPropertyChanged string void Addinterfaces XDocument List lt string gt property Behaviours XElement Dictionary lt string Behavior gt Duration int InterfaceManager Panel Interpolation string Renderinterface string void Value string property event Interfaces Dictionary lt string Interface gt PropertyChanged EventHandler Figure 5 Model and interface management class diagram 23 3 Design 3 0 5 Managing Interfaces Interface is the root element for all UI controls in UIP documents An application can contain a large number of interfaces We therefore need a class to keep the interface information InterfaceManager will serve as a place for storing information about received and requested interfaces The most important methods implemented in it will be for adding received interfaces obtaining an interface and rendering The process of rendering is described more closely in the next paragraph
3. Dictionary lt string Property gt Styles UipStyle class Document Container XElement Element XElement HandleNestediF XElement bool void property Interfacelnclusion XElement string Behaviours Dictionary lt string Behavior gt WaitForiface string Task lt Interface gt Class string property Elements List lt IRenderable gt Class string Position Position Elements List lt IRenderable gt Properties Dictionary lt string Property gt Layout Layout Styles UipStyle Position Position Properties Dictionary lt string Property gt Styles UipStyle Figure 4 Class diagram of the classes representing UIP interface container and element An important component is the IRenderable interface which is implemented by the Interface Container and Element classes This interface represents the function ality all of the classes have in common most importantly the UIP class i e type of the 22 UI control see 2 4 for example of public input text which represents the C s TextBox UIP properties and contained elements IRenderableContainer only extends the IRenderable interface by adding a method for obtaining layout Since layout is a container feature only Interface and Container classes will implement it 3 0 4 Managing Models and Binding To conform the UIP specification the client must be thin i e it will only store as much data as is needed to render the reg
4. In particular the extensions may include StackPanel layout panel The StackPanel is a simple layout panel that arranges its child elements into a single line that can be oriented horizontally or vertically Currently the app supports Grid and Canvas panels to which UI controls can be added StackPanel should be implemented to widen the choice of layout panels More UI controls The client comes with a small set of implemented UI controls New UI controls can be implemented Wider support for styling The app could support more font styles such as font family font decoration e g italic bold These features can be easily added Performance optimization The performance of the current client is satisfactory it could however be improved by technigues such as interface pre fetching Error handling The client ignores errors received from the server for example if a reguested interface is not found at the server It also assumes all data it receives is correct Support for different screen orientations When a user rotates the phone the UI remains the same This is not so important for the NUIP project but an UIProtocol client should have this feature implemented Support for Ul generator API Screen reader friendliness Currently the implementation redraws the whole UI when interface is embedded into another one This approach was chosen for its simplicity It is however discouraged by the accessibility guidelines for WP Additional acc
5. The solution uses a real time algorithm to match particular references extracted from pictures taken by a body mounted camera which periodically takes pictures of the surroundings The extraction uses 3D landmarks which the system first has to learn by going through a path along which the user later wants to navigate It follows that the system is not suitable in environments that are visited for the first time Accordingly to the authors for the case when it has learned the way the system performs well 15 2 Analysis 2 4 6 System by Ozdenizci et al Authors of 33 developed a system for general navigation and propose to use NFC tags They claim the NFC navigation system is low cost and doesn t have the disadvantages present with the systems which use dead reckoning or triangulation The proposed system consists of NFC tags spread in key locations of the building and a mobile device capable of reading the tags The device runs an application which is connected to a server containing floor plans The application is able to combine the information from the sensor with the floor plan and navigate the user using simple directions The paper only proposes a system and does not contain any testing 2 4 7 System by Luis et al Luis et al 34 propose a system which uses an infrared transmitter attached to the white cane combined with Wiimote units the device of the Wii game console The units are placed so that they can determine the use
6. are used extensively within many classes including Layout Event or Element In all classes they will be stored in dictionaries identified by their name The ModelProperty class used in Model will inherit from Property class 3 0 10 Layouts Windows Phone 8 supports two main types of layouts absolute and dynamic In an absolute layout child elements are arranged in a layout panel by specifying their exact locations relative to their parent element Absolute positioning doesn t consider the size of the screen In a dynamic layout the child elements are arranged by specifying how they should be arranged and how they should wrap relative to their parent With dynamic layout the user interface appears correctly on various screen resolutions Both layout types will be supported in our client Even though absolute layout is not recommended by the accessibility guidelines 39 it is a basic form of layout and decision has been made to support it Layouts are a feature of containers and interfaces which support it through the TRenderableContainer interface Every container therefore can place its content into one of the two layouts As with any property the positioning will be binding enabled 25 3 Design The client will support a container with scrollable content through ScrollViewer so that content which does not fit in the screen can be reached by scrolling 3 0 11 Configuration Client will have support for basic configurat
7. color is used to express some information developer has to keep in mind there might be color blind users who need an alternative like text or icons 39 Additional Guidelines There is a number of other guidelines for developing accessible applications For ex ample it is recommended to not automatically refresh an entire app canvas unless it is really necessary for app functionality This is because the screen reader assumes that 18 2 5 Windows Phone Accessibility Guidelines a refreshed canvas contains an entirely new UI even if the update considered only a small part of it and must recreate and present the description to the user again 39 Since Windows Phone 8 1 there is IsTextScaleFactorEnabled property avail able for every text element which if set to true will override the app s font size setting and set the font size to whatever value it was set by user in the Ease of Access control panel 39 19 3 Design After analyzing the problem this chapter will go through the design of the application architecture of our UIProtocol client The design phase is of crucial importance as it is the time when important design decisions are made In this phase the application s architecture needs to be thought through so that its future extensions are relatively easy to implement and cost of maintenance is low From the analysis we conclude requirements for the application which will be de veloped Further on the sec
8. connects to the server and goes through the connection procedure described in 14 the server sends the XMLs describing the UI The UML diagram of the classes responsible for the communication is shown in figure 3 Since some of the methods will only work with the passed parameters and not modify the object s state they will be made static _interfaceManager nterfaceManager _bw BackgroundWorker E Er er clientDone ManualResetEvent k ieee clientDone2 ManualResetEvent eh feral socket Socket null Connect string MaxBufferSize int HandleModelReceived XDocument void TimeoutMilliseconds int HandshakeStrin strin interfaceRequestString string strin bw DoWork object DoWorkEventArgs void InterfaceRequeststring string string Close void IsValidXmi string XDocument on Pa eee Launch string string ConnectClient string int string PO Receive void ProcessAnyXmiResponse string void Send string string Reguestinterface string void RequestPubli lication strin SendDataAsync string string UipConnection Panel dieters Figure 3 Class diagram of communication classes Apart from the mentioned classes that will serve for communicating the XML mes sages there there will be another class responsible for acquiring resources such as images from the server For this purpose the server is awaiting a HTTP connection on another port and the client can open a connection and make a standard HT
9. elements such as Panels or Grids do not provide their accessible name because it would in most cases be meaningless 39 Therefore containers are not covered in the table It is the container elements that carry the accessible name and other information not the container itself Role and Value Role is the type of the UI elements e g Button Image Calendar Menu etc 40 Every UI element therefore has a role Value on the other hand is only present at the UI elements that display some content to user e g TextBox The UI elements and controls that are the standard part of the Windows Runtime XAML set already implement support for role and value reporting 40 Keyboard Accessibility For screen reader users a hardware keyboard is an important part of application control as they use it to browse through the controls to gain under standing of the app and interact with it An accessible app must let users access all interactive UI elements by keyboard 39 This enables the users to navigate through the app by tab and arrow keys trigger an action e g a button click by space or enter keys and use keyboard shortcuts 39 Visual experience accessibility Some lightly visually impaired people elderly for example prefer to consume the apps content with increased font size and or contrast ration 39 Since WP8 1 an accessible app UI can scale and change its font size according to the settings in Ease of Access control panel If
10. makes it easily accessible from any point of the application Its purpose is to wrap the event into an UIP Document header and forward the event to Socket Worker class instance which does the actual job of sending it to the server 4 0 24 Constants The code contains a large number of string constants that are used to acguire XML elements from the XML documents or to create events that are sent to the server typically in static methods of the UipConnection or Event classes To make the maintenance of these constants easy they are all stored centrally in the Consts class and split into the following categories Ulelements All constants used while parsing the UIP documets into the inner object representa tion Examples are public scroll or public input text Events Constants used for constructing events such as public request interface Styling Constants that have to do with appearance of UI controls or layouts Examples include width font color or public grid General Constants that do not fit into any of the previous categories 4 0 25 Configuration The client connects to the UIP server and HTTP server on ports that are settled on by the specification ahead of time The port default IP address and socket buffer size are all stored in the Settings class where they can be easily modified 32 4 0 26 Problems in Implementation We encountered several problems in the development and some of them are described in this section Fi
11. place Therefore ModelManager is a singleton class The code which acquires the models and creates bindings between model proper 28 ties and properties of UI elements makes heavy use of asynchronous methods The async await operations were introduced with C 5 0 and provide the developer with a comfortable way to deal with operations that are potentially blocking Because reguesting and receiving models typically happens over a wireless connec tion it can be considered potentially blocking If a model reguest and its receiving was blocked within a synchronous process the entire application would be forced to wait However by taking advantage of the asynchronous programming the application continues with other work that does not depend on the web resource This is also the reason why sometimes the UI is drawn gradually This happens when properties refer to models which have to be reguested and received from the server for example if a button text color is specified in a model In such case the button is rendered with the standard text color and only once the model arrives the font color is changed to whatever value is specified in the model The delay before the update is noticeable but very short and therefore does not limit the app usage in any way The same happens to resources images from the HTTP server which are also fetched asynchronously 4 0 18 Interpolations animations Interpolation allows to move UI controls on the
12. support a range of languages Speech Features Users can interact with the phone using speech There are three speech components that a developer can integrate in her app and the user can take advantage of voice commands speech recognition and text to speech TTS We will explore these features in the following paragraphs At the time of writing the speech features support 15 major languages ranging from English to Russian or even English with the Indian accent Czech however is not supported To use the speech features the user has to download a language pack Speech Recognition Users can give input to an app or accomplish tasks with it using speech recognition An example usage can be dictating the content of a short text mes sage SMS 15 This is very similar to the Voice Command feature but the difference is that speech recognition occurs when user is in the app and Voice Commands occur from outside of the app 15 The second key difference is that the Voice Commands are defined on a finite and usually small set of words commands whereas the Speech Recognition should recognize words from a much larger dictionary in the ideal case a whole human language Voice Commands When a user installs an app they can automatically use voice to access it by speaking open or start followed by the app name 16 The range of actions that can be triggered by Voice Commands is much wider the full list of available speech commands tha
13. support for styling element dimensions and positioning Any particular UI element needs to inherit from the base class in order to support rendering model updates and other functionality provided by the base class 3 0 8 Events The application is designed to support the client to server communication in form of events Events are the only data sent by the client and their intent is to inform server of an user action or request missing data models 24 Events could be divided into two categories Static Events that are static and are hard coded within the application These events are used rarely typically while going through the procedure of connecting to the server Currently these are the public connection connect and public reguest model as well as public application Dynamic Other events are the ones triggered by the user or by the client itself when it reguests a model These events are dynamic created at runtime The event firing i e notifying server of an action taking place is a relatively simple process which will be handled by two classes Its working is described in the Implementation chapter EventManager AddProperty string string void SendEvent Event void AddProperty Property void Event string property Id string Properties Dictionary lt string Property gt Figure 7 event class diagram 3 0 9 Properties Properties are the most nested objects in UIP documents They
14. vi Introduction 1 Loz IMOLIVACIO z r ud seba te ch a A ets oe te aa ec BB ARA ce za by Sts 1 1 2 Assipnment 0 2 de su eb F Boa ea Bale ad bee eda es 2 1 3 Document Outline e 2 Analysis 4 2 1 About Windows Phone 8 e o 4 2 1 1 About CF and NET Framework 4 212 AULPTOLOCOL i usec a aa e das e hea cp s ba ZE i 5 2 2 1 About UIProtocol soss so sc ca eee Aa sad as 5 UlProtocol Cliente z a tie ted ala ga ee bodec p A 6 UlProtocol Server lt lt lt lt lt 4 444 444 44444444 7 2 2 2 Syntax of UIProtocol lt lt lt lt 44 44 lt 4 0002005 7 2 2 3 Elements of UlProtocol Communication 8 Tnitertaces 23 osipe d j A S a ln eee me O aa 8 Evens fos cach Seas aoe hye a E BA RE ae a a na 8 Models and Model Binding 9 2 3 Accessibility of Current Mobile Platforms 9 2 3 1 Windows Phone 8 Accessibility lt lt lt 4 4 44 9 Speech Features e 10 Other Tools for Ease of Access lt lt lt lt lt lt lt lt 11 Conclusi ns maca Gg a ER a RG Gok ee hed Goes 11 2 3 2 Android Accessibility o 022000 11 Speech Features lt lt lt 44 44 ee 11 Other Tools for Ease of Access lt lt lt lt lt e 4 12 CONClUSIONS a eas ia A je dokon A we 12 2 3 3 iOS Accessibility OER 00020208 12 Speech Features e
15. 01 04 2014 Narrator on Windows Phone 8 1 2014 URL http www windowsphone com en us how to wp8 settings and personalization use narrator on my phone visited on 05 14 2014 Microsoft releases Windows Phone 8 1 SDK Development Tools RC 2014 URL http www wpcentral com microsoft releases windows phone 81 sdk development tools visited on 05 20 2014 Android ends the year on top but Apple scores in key markets 2014 URL http www kantarworldpanel com Global News Android ends the year on top but Apple scores in key markets visited on 01 06 2014 Developing Android Applications with Voice Recognition Features 2014 URL https software intel com en us articles developing android applications with voice recognition features visited on 12 14 2013 Google Now 2013 URL http www google com landing now visited on 12 14 2013 Google Text to Speech 2013 URL https play google com store apps details id com google android tts visited on 12 14 2013 Android Accessibility 2014 URL http developer android com design patterns accessibility html visited on 01 04 2014 Android and iPhone accessibility comparison Switching to Android full time an experiment 2014 URL http www marcozehe de 2013 04 05 switching to android full time an experiment visited on 01 01 2014 iOS Accessibility 2013 URL https www apple com accessibi
16. 07 aspx visited on 05 04 2014 Exposing basic information about UI elements XAML 2014 URL http msdn microsoft com en us library windows apps hh868160 aspx visited on 05 06 2014 App monitoring for Windows Phone 8 2013 URL http msdn microsoft com en us library windowsphone develop 33215907 v vs 105 aspx visited on 05 15 2014 App profiling for Windows Phone 8 2013 URL http msdn microsoft com en us library windowsphone develop 33215908 v vs 105 aspx visited on 05 15 2014 43
17. 13 Other Tools for Ease of Access lt lt lt lt lt lt lt lt 44 13 COMCIUSIONS a ps aop a A Pa AG e SSS 13 2 3 4 Comparison of Analyzed Platforms 13 2 4 Navigation Systems Analysis lt lt lt 00000002 ee eee 14 ZA Navi Vernier ss 2104 2h a ug ae Ge aoe ea ee gh sky dob A v l vena He Del tn as 14 242 PERCEPT 2 9 5 zku e Gees Ae ee aD Pack alah wd 14 2 43 Blindshopping s ui do ed GBM eee ed ole eS 15 2 4 4 System by Riehle etal lt lt lt lt lt lt lt 15 2 4 5 System by Treuillet at al lt lt lt lt lt lt lt lt 15 2 4 6 System by Ozdenizci et al lt lt lt lt lt lt lt lt 16 2 4 7 System by Luis etal lt lt ee 16 DAB ODER T z ea Pos BE dock ee SR A doo ee a M 16 2 4 9 Conclusions and Comparison lt 4 16 2 5 Windows Phone Accessibility Guidelines 17 Reasons for Developing Accessible Applications 17 Screen Reading lt lt lt lt 4 ce 2 dd na ee es 17 Visual experience accessibility lt 4 4 18 Additional Guidelines lt lt lt e e 18 3 4 5 Design 3 0 1 Requirements Summary of Requirements 3 0 2 Client server Communication 3 0 3 Parsing XML Into Inner Object Representation 3 0 4 Managing Models and Binding 3 0 5 Managing Interf
18. 26 26 27 27 27 28 28 29 29 30 30 32 32 32 32 33 34 34 35 35 36 36 36 37 38 38 39 40 40 41 vil Abbreviations The list of abbreviations used in this document FEE CTU UIP UI WP WP8 WP8 1 TTS OS API NFC IDE XAML viii Faculty of Electrical Engineering of the Czech Technical University in Prague UI Protocol developed for research purposes at the FEE CTU User Interface Windows Phone Windows Phone 8 Windows Phone 8 1 Text to Speech Operating System Application Programming Interface Near Field Communication Integrated Development Environment Extensible Application Markup Language 1 Introduction Spatial navigation and mobility is an integral part of everyday living Whether a person wants to go on a field trip go shopping or visit a physician they need to be able to navigate themselves For certain groups of people however independent exercise of these actions is harder than for others These include especially visually and motor impaired elderly or people with other disabilities With today s development of technology there are new means of helping such peo ple to navigate in various environments without being dependent on another person s help Development of navigational solutions has been of interest of both commercial and academic research groups and with the availability of GPS there were great ad vancements in various fields ranging from navigation of individu
19. 50219467810003937 URL http www worldscientific com doi abs 10 1142 S0219467810003937 B Ozdenizci et al Development of an Indoor Navigation System Using NFC Technology In Information and Computing ICIC 2011 Fourth International Conference on Apr 2011 pp 11 14 pot 10 1109 1C1C 2011 53 Luis A Guerrero Francisco Vasguez and Sergio F Ochoa An Indoor Naviga tion System for the Visually Impaired In Proceedings of Sensors 2012 2012 pp 8237 8258 URL http www ncbi nlm nih gov pubmed 22969398 P Espinace et al Indoor Scene Recognition through Object Detection In Pro ceedings of the 2010 IEEE International Conference on Robotics and Automation 2010 pp 1406 1413 A Quattoni A Torralba Recognizing Indoor Scenes In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition 2009 pp 413 420 Anna Bosch Xavier Mu oz and Robert Mart Review Which is the Best Way to Organize Classify Images by Content In Image Vision Comput 25 6 June 2007 pp 778 791 ISSN 0262 8856 DOI 10 1016 j imavis 2006 07 015 URL http dx doi org 10 1016 3 imavis 2006 07 015 J A Hesch and S I Roumeliotis Design and analysis of a portable indoor local ization aid for the visually impaired In Int J Robot Res 2010 pp 1400 1415 Guidelines for designing accessible apps 2014 URL http msdn microsoft com en us library windows apps hh7004
20. Abstract Class D ITextStylable 2 TextStylable UipTextBlock y UipPanel y UipButton y Class Class Class gt UipBase gt UipBase gt UipBase ITextStylable MextStylable UipRadioBox h UiplmageCanvas Y UipTextBox Y Class Class Class gt UipBase gt UipBase gt UipBase Figure 8 Inheritance tree of several sample UI classes 4 0 21 Rendering Rendering is always triggered by InterfaceManager class which calls the Render method of Renderer class Part of method body is shown in listing 4 2 The method receives an IRenderable item i e instance of Interface Container or Element and a parent container The method traverses the tree of UI elements calling itself recursively if it encounters a container The foreach loop iterates over all elements in the container and creates a wrapper class for each of the IRenderables Note the graceful degradation taking place This wrapper class contains a platform native UI control and sets it up according to the TRenderable UipBase s Render method is called at the end of the foreach loop From then on rendering continues in the UipBase which adds all of the UI controls to the parent Panel this makes them visible to the user 30 public void Render IRenderable item object parent foreach var element in item Elements if element is IRenderableContainer Render element pass return UipBase uib null switch Gracefu
21. IP documents and define the visual appearance of UI controls their positioning content and much more They are heavily used in many UIP s structures in Models in styling and more Every property has to have a name which defines what feature of the connected object the property describes For example the property in listing 2 2 with name text defines the text displayed in the text field Value is a constant that will define the text The mentioned property can also contain a key attribute which if set binds the displayed value to a model property see the next paragraph lt element class public input text gt lt property name text key modelName modelPropertyName gt lt element gt Models and Model Binding Models serve as a storage for data Within models data is stored in properties which are uniquely identified by model name and name of the property within that model As explained in the previous paragraph properties can be used to define content and appearance of UI elements and more The property value can be provided as a constant or it can refer to a model using the key The key is separated by colon into two parts the first referencing a model and the second referencing a property within the model see listing 2 4 for an example For example consider the element in listing 2 4 The property representing the UI control s text contains a nonempty key It follows that the modelName model is requested from t
22. PI support The non functional requirements were also met The UI loading times are below 0 5 s in all interfaces of the testing application The execution profiling has shown increased CPU usage in some situations but when idle the consumption of phone s resources is normal 6 2 Accessibility On Windows Phone 8 the app accessibility could be improved by not redrawing the whole Ul when one interface is embedded into other Also support for voice commands could be added to UlProtocol Windows Phone 8 1 brings new accessibility features and ways to provide content to users with special needs particularly interesting is the Narrator screen reader or the option to increase font size in all apps UlProtocol can easily facilitate additional information that might be needed by these features such as alternative text for images 36 6 3 Future Work WP8 1 was released at a late stage of this work and therefore could not be incorpo rated in it much We tried to run the developed app on a WP8 1 emulator and explore the new features but the Hyper V feature reguired to run the emulator was not sup ported by our OS version We therefore could not directly evaluate the new platform This is a subject of future work as discussed in the next section 6 3 Future Work Implementing the full feature set of an UIProtocol client was not possible in the scope of this work Therefore there is a number of features by which the client could be extended
23. TP re quest for the resource This functionality will be implemented in the HttpConnection class 21 3 Design 3 0 3 Parsing XML Into Inner Object Representation After the UIP documents will be received by the UipConnection class they will be passed to instances of ModelManager and InterfaceManager classes ModelManager will be responsible for processing possible new models or model up dates and will be discussed later in more detail All of the UIP elements need to be represented by objects so that they are easily manipulated To create the object representation InterfaceManager class will pro cess the XML data that describes the UI by recursively traversing the XML tree and creating instances of Interface Container and Element classes based on the type of the considered XML node These instances will represent the UIP elements of the same name UIP interface UIP container and UIP element respectively This way every UIP element will be parsed into an inner object representation that will be easy to handle in further work with the objects interface Renderer Renderable Renderer IRenderableContainer ECT Elements List lt IRenderable gt Position Position Properties Dictionary lt string Property gt Styles UipStyle Interface string Interface XElement property Class string Container IRenderable Elements List lt IRenderable gt Layout Layout Position Position Properties
24. aces 3 0 6 Rendering the Ul 3 0 7 Representing the Platform native UI Components 30 85 Bv nbS ics A ek ce dob eee ap a E 3 0 9 Properties lt lt lt 44 3 0 10 Layouts lt lt lt 44 4 3 0 11 Configuration lt lt 3 0 12 Behaviors lt lt 3 0 13 Interpolation lt lt lt lt Implementation 4 0 14 Development Environment 4 0 15 Overview of the Core Classes 4 0 16 Communication With UIP Server 4 0 17 Model Updates and Binding 4 0 18 Interpolations animations 4 0 19 Binding Converters 4 0 20 Implementing the UI Element Classes 4 0 21 Rendering 4 0 22 Graceful Degradation 4 0 23 Event Communication 4 024 Constants noni Be aS 4 0 25 Configuration 4 0 26 Problems in Implementation Testing 5 1 Functional Testing 5 2 Unit Testing lt lt 4 5 3 Monitoring and Profiling Conclusions and Future Work 6 1 Current Features 6 2 Accessibility o 4 4 44 6 3 Future Work Appendices A Speech Accessibility Features A 1 Windows Phone Speech Commands A 2 Android Speech Commands User Manual B 1 Contents of the Attached CD Bibliography 20 20 20 21 22 23 24 24 24 24 25 25 26
25. als on roads and in cities to agriculture and marine or aviation applications Still indoor navigation where GPS or similar systems typically are not available remains a not so developed part of the field Various tools are used to navigate people indoors such as maps and visual navigation systems including banners signs on the floor flashing light and etc These systems however assume that their user does not suffer from visual impairment and generally is able bodied Indeed research shows that for a healthy person sight accounts for 70 90 of infor mation that the brain receives 1 Visually impaired therefore lack the most important information source and have to use their other senses and assistive tools to navigate and orient themselves It should be noted that there are situations when not only visually impaired have problems to orientate themselves In large and complex buildings such as hospitals airports university or government facilities and other navigating can be a tough task even for a healthy and fit person 1 1 Motivation The World Health Organization states 2 there are 285 million people estimated to be visually impaired worldwide of whom 39 million are blind and 246 have low vision Also the number of elderly people who often suffer some form of motor or other impairment is growing This is true especially in the developed economies of western Europe USA or Japan and according to the US Census Bureau re
26. ane acts as an RFID reader and communicates with a smartphone which as in other projects uses TTS to give directions The Android application is also used for product recognition using embossed QR codes placed on product shelves The authors conducted a small usability study from which no conclusions can be drawn 2 4 4 System by Riehle et al An indoor navigation system to support the visually impaired is presented in 31 The paper describes creation of a system that utilizes a commercial Ultra Wideband UWB asset tracking system to support real time location and navigation information The paper claims that the advantage of using UWB is its resistance to narrowband interference and its robustness in complex indoor multipath environments The system finds user position using triangulation and consists of four parts tracking tag to be worn by the user sensors that sense the position of the tracking tag handheld navigator and a server which calculates the location of the tracking tag and communicates it to the navigator The handheld device runs software which can produce audio directions to the user In tests the system proved useful it was however tested only on blindfolded subjects Testing showed that they found their way faster with the navigation system 2 4 5 System by Treuillet at al Treuillet and Royer 32 proposed a computer vision based localization for blind pedes trian navigation assistance in both outdoors and indoors
27. as a container for more UI elements This class has its own position a Container instance and can be embedded into another interface as specified in listing 2 2 Container This class stores the information about particular UI elements A Container can contain instances of other Containers and instances of Element class Element Class representing particular UI elements such as button textbox and more 27 4 Implementation Table 5 UIP Server connection classes UipConnection Initiates the connection and is responsible for sending events to the server and processing its responses Does basic XML validation Socket Worker Handles the socket communication with UIP server Sends events and runs a separate thread for receiving server s re sponses HttpConncetion Class responsible for acquiring resources via HTTP Table 6 ModelManager and InterfaceManager classes ModelManager Keeps and updates all reguested and received models Is imple mented as a singleton class InterfaceManager Stores all received interfaces Provides getter method and method for rendering an Interface Is also implemented as a singleton 4 0 16 Communication With UIP Server As shown in table 5 the communication with server is implemented in UipConnection class which exposes its functionality for sending events to the rest of the application namely the EventManager class It also is responsible for processing any XML data
28. as to describe the application once and the application then runs on all platforms with UIP client implementation This should simplify the development process and make one application easily available to multiple platforms UlProtocol client uses platform native UI components which makes it different from HTML based applications UIProtocol is an application protocol that allows for describing the hierarchical struc ture of GUIs along with the placement and visual appearance of the containers and components It is designed for a client server system and for facilitating client server applications it defines the communication rules between the two The communication is based on exchange of XML or other supported documents The client first initiates the communication and receives a UI description document from the server The description can be of two different types interfaces i e the UI components and containers and models which contain the data displayed in the UI components The communication from client to server only consists of event descriptions that is actions that the user has done e g a button click The architecture of UIProtocol is shown in figure 1 which also indicates the information flow between the client and server The figure also shows Actions which are an advanced optional feature and we will not cover it Thttp www iso org iso home store catalogue tc catalogue detail htm csnumber 42926 2http www ecma interna
29. ate a mental model of the presented UI Information conveyed by the screen readers includes details about the UI elements and visually impaired users depend heavily on it Therefore it is important to present it sufficiently and correctly A correctly provided UI element information describes its name role description state and value 39 Name Name is a short descriptive string that the screen reader uses to announce an UI element to the user 39 It should be something that shortly describes what the UI element represents For different elements this information is provided differently The Table 3 gives more details on accessible names for different XAML UI elements 17 2 Analysis Table 3 Accessible name for various UI elements Static text UI elements For TextBlock and RichTextBlock elements an ac cessible name is automatically determined from the visible inner text All of the text in that element is used as the name Images The XAML Image element does not have a direct analog to the HTML alt attribute of img and similar elements WP8 does not provide an alternative text WP8 1 provides AutomationProperties Name Buttons and links The accessible name of a button or link is based on the visible text using the same rules as described in the first row of the table In cases where a button contains only an image WP8 does not provide an alternative text WP8 1 provides AutomationProperties Name The container
30. ations when a model update is sent from the server including a linearly interpolated model update which is used to animate the position of a button Interface embedding This test evaluates whether embedding nesting one interface into other works as expected Interfaces can be included using both UIP element and container Model wide binding In our testing application we bound several properties to models The binding was tested with text color text size position of UI control interpolation integer value Events Testing application contained several events that were triggered by different user actions The events were sent by different button presses button radiobutton and using several UIP Behaviors Table 8 Testing device details Phone model HTC 85 OS version 8 0 10327 77 Screen resolution 480x800px RAM 512MB Processor Qualcomm 4 1 GHz Dual core 34 5 2 Unit Testing 5 2 Unit Testing To widen the coverage of testing we also added unit tests of the core functionality They are added as a separate Visual Studio project The tests all pass 5 3 Monitoring and Profiling Visual Studio contains several features that help to understand the guality of the ap plication ranging from code analysis to profiling The app monitoring feature aims to capture key metrics that are relevant from a guality perspective and then to rate the application based on these metrics 41 The goal of profiling is to
31. bachelor s thesis Accessible UIP client for Windows Phone 8 Vojt ch Nov k May 23 2014 Mac k Miroslav Ing Czech Technical University in Prague Faculty of Electrical Engineering Dept of Computer Graphics and Interaction Acknowledgement I would like to thank my advisor Ing Miroslav Mac k for his help and explanations of UIProtocol Also I would like to thank my family for continuous support in my studies for which I am very grateful Lastly I want to thank all my friends from the International Student Club CTU in Prague who made this past year very special and supported me a great deal Declaration I declare that I worked out the presented thesis independently and I guoted all used sources of information in accord with Methodical instructions about ethical principles for writing an academic thesis Prague May 23rd 2014 GG GG Gr iii Abstract UIProtocol je jazyk pro specifikaci u ivatelsk ch rozhran je je vyv jen na FEL VUT pro ely v zkumu Je navr en jako klient server syst m kde server m k dispozici sou bory popisuj c aplikaci a jej u ivatelsk rozhran Tento popis je poskytnut klientu kter vykresluje ono u ivatelsk rozhran informuje server o akc ch u ivatele a zpra cov v odpov di serveru na tyto ud losti Tato pr ce popisuje v voj p stupn ho UI Protocol klienta pro platformu Windows Phone 8 Tento klient je vyv jen jako sou st koplexn ho naviga n ho s
32. canvas Because interpolation uses model updates the prereguisite for it is that the UI control s coordinate which we want to change is bound to a model e g if we want to move a button horizontally we need to bind the x coordinate of its Position to a model property It is triggered by an event which is fired by activating some UI control The server responds by a model update whose body contains interpolation and duration attributes An example of such model update is shown in listing 4 1 lt UIProtocol version 1 0 gt lt models gt lt model id cz ctu bp sampleModel update partial duration 500 interpolation public number linear gt lt property name x value 100 gt lt model gt lt models gt lt UIProtocol gt Interpolation works through model wide binding The ModelManager when it receives an interpolation model starts a new Task which periodically updates the given property value property x considering our example Because of the data binding this update also triggers update of the UI control s position on the canvas which causes the UI control to move animate 4 0 19 Binding Converters It has been said that any property can be bound to a model However properties in UIP document can convey a wide range of information including color font size row and column position in a grid and etc Since the model updates are always received as string the binding has to be provided with a converter whic
33. em works on a principle of sequential presentation of carefully prepared description of the building to the user by the mobile phone voice output This system does not keep track of the user location Instead it breaks the directions into small pieces and then sequentially gives the pieces to the user who follows them and asks for next portion when ready This system is being integrated with UI Protocol platform which is another research project of FEE CTU developed for the purpose of creating user interfaces customized to abilities and preferences of individual users The result is navigation system called NaviTerier UIP NUIP 5 which combines the navigational part of NaviTerier and UIP the context sensitive UI generator that can adapt the user interface based on several criteria device navigation terminal smartphone etc user visually impaired elderly and environment inside outside etc Over the course of development the system has been tested several times with a total of about 100 visually impaired 2 4 2 PERCEPT A promising approach toward an indoor navigation system is shown in the PERCEPT 29 project Its architecture consists of three system components Environment the Windows Phone 8 1 contains a screen reader feature called Narrator 2 Google Indoor Maps https www google com maps about partners indoormaps 14 2 4 Navigation Systems Analysis PERCEPT glove and an Android client and the PERCEPT serv
34. eople on earth by the end of 2014 The world smartphone market is dominated by three main platforms Android with market share of about 78 iPhone with 17 and Windows Phone with 3 8 Since the thesis is developed with the NaviTerier in mind it is clear we will develop a client for one of the mobile platforms UIProtocol clients for iPhone and Android are already implemented and we have therefore chosen Windows Phone as the platform we will develop for Reports show that Windows Phone is experiencing an overall growth in the world market 8 Recently Microsoft released a new version of the OS Windows Phone 8 1 and we assume that Windows Phone will keep or strengthen its position which is also indicated by a report 9 from idc Before moving onto the design and implementation we will introduce the technol ogy used for development an analysis of UIProtocol an overview of other navigation systems and an accessibility analysis of the current mobile platforms 2 1 About Windows Phone 8 The Windows Phone 8 is the first of Microsoft s mobile platforms to use the Windows NT Kernel which is the same kernel as the one in Windows 8 10 Therefore some parts of the API are the same for both systems A significant subset of Windows Runtime is built into Windows Phone 8 with the functionality exposed to all supported languages 11 This gives a developer the ability to use the same API for common tasks such as networking working with sensor
35. er In the environment there are passive i e no power supply needed RFID tags R tags deployed at strategic locations in a defined height and accompanied with signage of high contrast letters and embossed Braille The users part of the environment are kiosks Kiosks are where the user tells the system her destination They are located at key locations of the building such as elevators entrances and exits and more The R tags are present here and the user has to find the one she needs and scan it using the glove The glove is used to scan the R tags and also has buttons on it that the user can press to get instructions for the next part of the route repeat previous instructions and get instructions back to the kiosk Also after scanning the R tag the glove sends its information to the app running on user s Android phone The Android app connects to the internet and downloads the directions from the PERCEPT server These are then presented to the user through a text to speech engine and the user follows them The system was tested with 24 visually impaired users of whom 85 said that it provides independence and that they would use it 2 4 3 Blindshopping Another example of where RFID is used for indoor navigation is presented by Lopez et al 30 The system is devised to allow visually impaired people to do shopping autonomously within a supermarket The user is navigated by following paths marked by RFID labels on the floor The white c
36. essibility features based on WP8 1 An accessibility analysis of WP8 1 should follow assessing the changes that should be made to UIProtocol and the client to take the full advantage of WP8 1 37 Appendix A Speech Accessibility Features The following two tables describe the speech commands which can be used in WP8 and iPhone respectively A 1 Windows Phone Speech Commands Table 10 Windows phone 8 speech commands from 16 Call someone from your contact list Call contact name where contact name is the name of someone in your contact list If the person has only one phone number in your contact card the call will start If he or she has multiple phone numbers you ll see an option to choose one Call any phone number Call phone number where phone number is any phone number whether it belongs to a contact or not Redial number the last Redial Send a text mes sage Text contact name where contact name is the name of some one in your contact list This will start a text message to that person Then you can dictate and send the message hands free Call your voice mail Call voicemail Open an applica tion Open application or Start application where application is the name of any application on your phone such as Calendar Maps or Music Search the web 38 Find search term or Search for search term where search term is what you re lo
37. f access which can help lightly visually impaired users User can change font size in selected built in apps The API for determining if the font size was changed by user is available only from WP 8 1 and the app developer can decide whether she will respect the user font size settings 17 switch the display theme to high contrast colors and use the screen magnifier 18 Mobile Accessibility is a set of accessible apps with a screen reader which helps use the phone by reading the application content aloud These applications include phone text email and web browsing 18 When Mobile Accessibility is turned on notifications like alarms calendar events and low battery warnings will be read aloud This feature however is only available in version 8 0 10501 127 18 or later For an unknown reason an update to this version is not available for our device Windows Phone 8 1 contains a new accessibility feature called Narrator which allows to read aloud the content of the screen 19 The feature is intended for visually impaired but since the WP8 1 SDK was released in April 20 and the Windows Phone 8 1 devices are yet to come we did not have the chance to evaluate the feature Conclusions Windows Phone 8 platform offers some features to make its usage to users with special needs more pleasant However there are still gaps to be filled such as the non existence of a built in screen reader Its absence puts Windows Phone 8 out of the que
38. from different base classes and provide different interfaces for setting their text For example the text of the Button class is indicated by Content property whereas the text of TextBlock is indicated by Text property Also some components such as combo boxes have multiple items whose text can be set Therefore we introduced the ITextStylable interface which contains methods for setting the text and for binding 33 5 Testing Testing is an important part of any application s development cycle By testing we want to show that the client is able to process valid UIP documents We will perform two types of tests test using an verification UIP application on a Windows Phone 8 device and unit tests Visual Studio offers means for running and debugging the application 5 1 Functional Testing Testing was primarily done by directly running the developed solution on a HTC device whose details are listed in table 8 For the purpose of testing we developed a testing app written in UIProtocol XML which was then run on the client The testing application covers the following scenarios Interface switching Switching of the interfaces is one of the basic tasks a UIProtocol client has to imple ment since this is the mechanism of navigating through the application Our testing app contains several interfaces with different UI components and layouts Models and their updates including interpolated The testing application contains several situ
39. h considering the given examples converts the received string to SolidColorBrush double and integer types respectively All of our converters implement IValueConverter interface which is the standard way to apply custom logic to a binding 29 4 Implementation 4 0 20 Implementing the UI Element Classes When deciding how to represent the platform native components which are displayed to the user we chose to use wrapper classes which will expose the wrapped object s methods and at the same time be able to set up its properties from an instance of Element class i e from the inner object representation All supported native components are therefore wrapped into other classes whose names indicate the enclosed UI element e g UipButton is a wrapper class of the stan dard Button class All of these wrapper classes inherit from abstract class UipBase which provides common support for model binding for all inherited components This way adding new UI components with binding support is made easy The ITextStylable interface is implemented by classes which contain text which can be styled For example a UipTextBlock implements this interface in order to be able to set font size color and more UipPanel on the other hand does not implement it because a container itself does not have any text to be styled The figure 8 shows a class diagram of a few wrapper classes and also Text Stylable being implemented UipBase y
40. has been said that the app architecture was not influenced by any of the ex isting implementations The client server communication however was observed from another already implemented client Inspecting the communication logs helped to develop this client 4 0 14 Development Environment As previously said the application was written in the Visual Studio 2013 IDE and using C a programming language developed by Microsoft The reasons for choosing Visual Studio VS are clear VS is the main development tool for the whole NET platform fully supports C and Windows Phone development and debugging VS is therefore the main tool to be used for most NET development The programming was backed up by running the code directly on a Windows Phone 8 device namely HTC 85 We also used ReSharper a useful plugin for code inspection maintenance refactoring and coding assistance 4 0 15 Overview of the Core Classes In this section we will cover the most important classes of the application to give a brief idea of how the UIP documents are handled stored processed and how the UI is rendered There are several tables in the following pages documenting classes for inner UIP Document representation table 4 rendering support table 7 the communication with the server table 5 and the classes for management of interfaces and models table 6 Table 4 UIP Document representation classes Interface This class represents the UIP interface
41. he computing into a white cane However the solution has the limitations of being too heavy and large 2 4 9 Conclusions and Comparison There are two main approaches to the problem of navigation In the first the navigation system consists of active parts which using triangulation or other methods are able to determine the user s position at all times and then give her directions based on knowing where she is In the second approach the system does not possess the information about user s position at all times Instead it synchronizes the position at the beginning of the Dead reckoning The process of calculating one s position by estimating the direction and distance travelled rather than by using landmarks or astronomical observations Triangulation is the process of determining the location of a point by measuring angles to it from known points at either end of a fixed baseline rather than measuring distances to the point directly 16 2 5 Windows Phone Accessibility Guidelines navigation task and then gives the user directions broken into small chunks When the user believes she reached the destination described by the first chunk she asks for the next one and etc The disadvantage of this approach is that the user can get lost and not end up at the expected location This problem can be solved by adding more synchronization points to strategic locations of the building These synchronization points are often done t
42. he server Upon its arrival the modelPropertyName property is looked up in the model and the text of the UI control is set to this UIP property s value Also a data binding between the modelPropertyName property and the UI element s text property is created so that when the client receives an update of the modelPropertyName property the UI element s text gets immediately updated When updating the value of a model property all UI elements bound to the model property are updated For example there may be two representations of humidity level in a given environment text and a graphical representation If they are both bound to the same model property update of the given property will be immediately reflected by both Note that Models in UIP are application wide so they can be referred to from any point of the application 2 3 Accessibility of Current Mobile Platforms In this section we will analyze the accessibility features of today s most common mobile platforms Windows Phone Android and iPhone Since this thesis is about develop ment of a UIP client for Windows Phone 8 we will put an emphasis on this OS 2 3 1 Windows Phone 8 Accessibility For the purposes of this project we are particularly interested in features that may help users with special needs From this point of view one of the most important are the 2 Analysis voice commands and speech recognition features which Windows phone 8 has built in and which
43. help understand the performance of an application 42 Visual Studio offers app performance testing using Execution and Memory profilers Execution profiler analyzes the performance of drawing visual items and method calls in the code 42 Memory profiler analyzes object allocation and the use of textures in the app 42 We performed all of the tests and summarized the results into table 9 The results revealed that sometimes the application probably has a high CPU usage Significant bugs or errors were otherwise not found However it must be noted that the testing application was not large scale and so the testing might not have been thorough Table 9 Results of monitoring and profiling Monitoring App startup time meets requirements App is responsive Execution profiler In some parts throughout the profiling execution profiler reports high CPU usage by system threads Memory profiler No issues found Full content of one of the reports System and other apps are using 32 71 of the CPU This CPU usage may be caused by other tasks that are running on the system or they may be caused by system operations that are triggered by our app 35 6 Conclusions and Future Work Navigation and mobility are key abilities to a comfortable living Navigating outdoors is thanks to global systems such as GPS significantly simplified Indoor navigation remains a less developed field There are research projects that develop solution
44. her This is done by an element or container with class name corresponding to different interface s class The interfaces are uniquely identified by the class attribute unlike most other objects in UlProtocol and other markup languages identified by id attribute lt interfaces gt lt interface class ui Interfacel gt lt interface description gt lt interface gt lt interface class ui Interface2 gt lt container class public container panel gt lt element class public input text id nameTextBox gt lt property name text value Enter first name gt lt element gt lt element class ui Interfacel gt lt container gt lt interface gt lt interfaces gt Events Events inform the server that some action was triggered at the client side e g a button press or that there was some other update e g change in sensor readings This is the mechanism of client to server communication and therefore has to be supported by the client The event element contains a unique id which specifies the event source An event can contain any number of properties which describe it in greater detail An example is shown in listing 2 3 lt events gt lt event id login gt lt property name username value user gt lt property name password value pass gt lt event gt lt events gt 2 3 Accessibility of Current Mobile Platforms Properties Properties are the most nested elements of U
45. hrough NFC tags A quick review of the analyzed navigation systems is given in table 2 Table 2 Quick comparison of the analyzed navigation systems NaviTerier mobile device kiosk visually impaired PERCEPT RFID mobile device kiosk visually impaired Blindshopping RFID mobile device visually impaired Luis et al infrared Wiimote mobile de blindfolded users vice Riehle et al UWB tracking system mobile blindfolded users device Treuillet at al camera laptop not found Ozdenizci et al NFC mobile device not relevant 2 5 Windows Phone Accessibility Guidelines Microsoft specifies a set of rules that ought to be followed by a developer in order to create an application which is friendly toward users with special needs which is called Guidelines for designing accessible apps and is accessible online 39 If a developer follows the principles of accessible design the application will be accessible to the widest possible audience Reasons for Developing Accessible Applications Users of an application may have different kinds of needs By keeping in mind the rules of accessible development a developer can improve the user experience Also it is one of the goals of this work to develop an accessible UIProtocol client In the rest of the section we will cover several accessibility scenarios Screen Reading Users who have some visual impairment or are blind use screen readers to help them cre
46. igation description generator which creates description of the route with respect to the users limitations was developed Finally a context sensitive UI generator 6 adapts the user interface according to navigation terminals and personal devices used during the navigation For this system to be available to as wide a set of users we need to have UIP clients for the most common smartphone platforms So far UIP clients are built for Windows iOS and Android Since there is no client for Windows Phone 8 WP8 within this thesis we intend to build a UIProtocol client application for this platform 1 2 Assignment The goal of this thesis is to develop an accessible UIProtocol client for Windows Phone 8 We will analyze the UIProtocol and introduce the reader to its features and architecture Since the developed client is intended to work in conjunction with the NaviTerier project we will also cover the state of the art of indoor navigation systems The platform of development was chosen to be Windows Phone 8 Still we will perform an accessibility analysis of the most common smartphone platforms to be able to compare the platform s friendliness toward users with special needs and put it into the context of its competitors The main part of the thesis is the actual development of the UIProtocol client which will be covered extensively The last task is to verify the functionality of the imple mented client for which we developed a testing applica
47. ile platforms that we analyzed is given in table 1 The table compares the three analyzed platforms 13 2 Analysis based on features that are important for visually impaired users It can be easily seen that to date iOS has the widest support for accessibility Table 1 Quick comparison of the accessibility features of today s mobile platforms Windows no yes yes no Phone 8 Android yes yes yes no iPhone yes yes yes yes 2 4 Navigation Systems Analysis There is a number of research projects in the field of navigation systems for disabled A large number of them are oriented toward visually impaired or people with movement disabilities Generally speaking there are ongoing efforts to create maps for indoor en vironments with the Google Indoor Maps being the head of this movement Currently the Google Indoor Maps are in beta and are not a priori intended for navigation but merely to provide the user with an approximate idea of where they are In this chapter we will analyze some of the existing works which specifically address the problem of indoor navigation 2 4 1 NaviTerier NaviTerier 4 is a research project at FEE CTU which aims at the problem of navi gating visually impaired inside buildings This system does not require any specialized technical equipment It relies on a mobile phone with voice output which for a visually impaired is a natural way of communicating information The navigation syst
48. ion i e the default IP address and ports on which the socket is tying to connect to the UIP and the HTTP server Also the constants which are used in the portions of XML throughout the application will be stored in one static class so that they are easy to maintain 3 0 12 Behaviors Behaviors are used to attach event listeners to UI controls C has a built in support for events through Event and Delegate classes and we will take advantage of it Behaviors will be attached to the classes inheriting from UipBase as event handlers Each handler is for one type of behavior and when the event is fired the event handler catches it 3 0 13 Interpolation The client will support interpolation of UI controls In the context of UIProtocol in terpolation means animation of UI elements For example some action may trigger interpolation which will cause an UI element to move on the screen of the phone A model update will specify the direction duration and position where the UI element should move UIProtocol specifies multiple types of interpolation our client will only support linear public number linear and immediate public immediate in terpolations 26 4 Implementation After providing an analysis of UIProtocol settling down on the reguirements and work ing out the design of the app we can now present how the application was developed what technologies were used what problems were encountered and how they were tack led It
49. lity ios visited on 12 14 2013 iOS VoiceOver 2013 URL https www apple com accessibility ios voiceover visited on 12 14 2013 Aura Ganz et al PERCEPT Indoor Navigation System for the Blind and Visu ally Impaired Architecture and Experimentation In Int J Telemedicine Appl 2012 Jan 2012 19 19 19 19 ISSN 1687 6415 DOI 10 1155 2012 894869 URL http dx doi org 10 1155 2012 8948609 31 32 33 34 35 38 39 40 41 42 Bibliography Diego L pez de Ipi a Tania Lorido and Unai L pez Blindshopping Enabling Accessible Shopping for Visually Impaired People Through Mobile Technologies In Proceedings of the 9th International Conference on Toward Useful Services for Elderly and People with Disabilities Smart Homes and Health Telematics ICOST 11 Montreal Canada Springer Verlag 2011 pp 266 270 ISBN 978 3 642 21534 6 URL http dl acm org citation cfm id 2026187 2026232 N A Giudice T H Riehle P Lichter An Indoor Navigation System to Support the Visually Impaired In 30th Annual International IEEE EMBS Conference 30 2009 pp 4435 4438 SYLVIE TREUILLET and ERIC ROYER OUTDOOR INDOOR VISION BASED LOCALIZATION FOR BLIND PEDESTRIAN NAVIGATION ASSISTANCE In International Journal of Image and Graphics 10 04 2010 pp 481 496 Dot 10 1142 50219467810003937 eprint http www worldscientific com doi pdf 10 1142
50. llyDegrade element Class case Consts UIelements TextBox uib new UipTextBox element break case Consts UIelements InputTime uib new UipTimePicker element break if uib null uib Render pass UI elements can be rendered into containers with absolute or grid layouts If the in terface is larger than the screen dimensions it should be put into the public scroll container That ensures it is rendered into a scrollable container making all its elements reachable for the user When using public scroll the position tag specifying interface dimensions should be placed as an direct ancestor If the dimensions are not provided the client will assume the interface has screen dimensions The InterfaceManager is implemented as a singleton because we only need one place to store the Interface instances Table 7 contains an overview of the classes taking care of the rendering mechanism Table 7 Classes ensuring the rendering of UI elements Renderer The main class responsible for rendering the elements stored in the classes of table 4 Its rendering method walks through the tree structure of UIP Document and invokes rendering of each element It also does the graceful degradation of unsupported elements IRenderable An interface which defines methods for acguiring class style position and other properties of UIP elements It is implemented by all classes in table 4 IRenderableCon Extensi
51. more than 40 languages including even minor languages such as Czech The text to speech only supports the world s most common languages 11 2 Analysis Speech Recognition Users can give input to an app or accomplish tasks with it using speech recognition An example usage can be dictating content of an SMS As men tioned above this feature supports many languages but on the other hand internet connection is required 22 because the recognition is done at Google servers We do not consider this a drawback as the UIP client assumes internet availability anyway Voice Action Commands In Android Voice Action Commands are closely related to the Google Now feature Google Now has a wide range of uses It can also serve well to users with special needs because it allows to get information using voice In general Google Now should provide the user with relevant information when they need it Google describes it by the phrase The right information at just the right time This includes telling the user the weather forecast showing the best route to work calling someone creating a reminder and more 23 The full list of Voice action Commands is in table 11 Appendix A Note that for some commands the system gives the user a spoken answer The current drawback of the system is that it only supports English French German Spanish and Italian 24 With other languages user can only make a voice induced Google search with no voice respo
52. n i e no application code is executed on the client side 14 The device running the client is thought to be the one user directly interacts with that is it renders the content to the user and receives input from her From the UIProtocol point of view the client device is also considered insecure i e the device may be misused to send invalid data to the server and may be used to attack it The UIP client may not implement the whole feature set defined by UlProtocol 14 What has to be implemented is the minimal functionality i e a client that is able to render user interfaces send event information to the server and update the application by data coming from it A use case diagram of actions performed by user in the client 2 2 UIProtocol app is shown in figure 2 UlProtocol Server UIProtocol server is the part of the architecture which is responsible for evaluating the client events and sending a correct response this is where the application logic is executed 14 Server must be able to service multiple clients simultaneously and is intended to run on a machine which is considered safe 14 A use case diagram of server actions is shown in figure 2 uc Use Case Model UlProtocol client o Send UI om Description em rem Figure 2 Use case diagram for user and server 2 2 2 Syntax of UlProtocol The UIP document syntax in listing 2 1 shows the four possible tags and the root element with the actions tag being
53. nse Text to Speech TTS TTS can be used to speak text to the user via the phone s speaker or headset The spoken text can be simple strings The industry standard Speech Synthesis Markup Language SSML is not mentioned in the API documenta tion Supported are only major world languages enlisted in the previous paragraph TTS is also used in TalkBack which is described in the next paragraph Other Speech Features TalkBack is an important functionality that strives for more accessible phone control for visually impaired 25 Basically it is a touch controlled screen reader When enabled user can drag finger across the screen selecting the components and getting their acoustic description By double tapping anywhere in the screen user can open use the last selected item TalkBack also supports gestures This way a user can get a complete description of the user interface 25 The blog post of a blind accessibility engineer from Mozilla Foundation 26 claims that visually impaired users of this system still have to overcome some obstacles Other Tools for Ease of Access Android too comes with more features for ease of access which can help lightly visually impaired users which include change of font size and a screen magnifier Conclusions To date Android has better accessibility options when compared to Windows Phone especially for visually impaired Android comes with the usual functions such as text to speech speech recognition o
54. oking for If you say Find local pizza for example Bing will bring up a map of nearby pizza places A 2 Android Speech Commands Open A 2 Android Speech Commands Table 11 Android speech commands from 23 App name Open Gmail Show me my schedule for the weekend Say What does my day look like tomorrow to see tomor row s agenda Create a calen dar event Event description amp day date amp time Create a calendar event Din ner in San Francisco Saturday at 7 00PM Listen to TV Displays TV cards relevant to the TV show that s currently being broadcast While a TV show is being broadcast say Listen to TV Map of Address name business name type of business or other loca tion Map of Golden Gate Park San Francisco Directions to or Address name business name type of business or other des tination Directions to 1299 Colusa Av enue Berkeley California or Navigate to Navigate to Union Square San Francisco Post to What you want posted to Post to Google I m going Google Google out of town What s this When you hear a song ask song What s this song Remind me to What you want to be reminded about and when or where Remind me to call John at 6PM Go to Search string or URL Go to Google com Send email To amp contact name Sub ject am
55. on of TRenderable interface It provides support for tainer layouts and is implemented by instances of Interface and Con tainer 31 4 Implementation 4 0 22 Graceful Degradation Graceful degradation is a mechanism which replaces unsupported UI elements by sup ported ones while rendering is being done This replacement of course does not happen without loss To illustrate this let us consider the following example Server asks the client to render an element of class public input choice single an UI element known under the WP8 platform as ListPicker This element however may not be supported by the client If this is the case the graceful degradation takes place and degrades this to public input choice which will be rendered as a group of radiobuttons assuming this basic UI element is supported If the graceful degradation does not find a suitable ancestor an empty TextBox is rendered instead 4 0 23 Event Communication Event management is relatively simple two classes take care of it Event class represents a particular event that will be sent to the server It contains all the necessary information for the server to be able to identify the event that has been triggered as specified in 14 This identification information is stored in properties that are attached to the object EventManager class provides a method for sending an event The class does not contain any state and is therefore static which
56. optional The tags define the behavior of the application and are covered later in the chapter with the exception of the actions tag Every UIProtocol document must contain an XML header with the version and en coding UTF 8 recommended lt xml version 1 0 encoding UTF 8 gt lt UIProtocol version 1 0 gt lt interfaces gt lt interface deinitions gt lt interfaces gt lt models gt lt model definitions gt lt models gt lt events gt lt event definitions gt lt events gt lt actions gt lt action definitions optional gt lt actions gt lt UIProtocol gt 2 Analysis 2 2 3 Elements of UlProtocol Communication As mentioned previously the information exchange between client and server concerns interfaces and models which are sent from server to client and events sent from client to server In the following subsections we will describe these in greater detail and also include more information on UIProtocol syntax Interfaces Interface describes the structure and components of the user interface Every interface can nest containers and elements that form a part of user interface An example can be seen in listing 2 2 The listing includes containers and elements of different types for example public input text is a standard component which will be rendered as an UI control into which the user can enter text It also shows how one interface can be embedded into ot
57. orms without being rewritten 13 The CLR is Microsoft s implementation of the CLI stan dard Other CLI implementations include Mono DotGNU Portable NET and other In NET C source code is compiled into Common Intermediate Language and stored in an executable file typically with exe or dll extensions 13 When executing the program the CLR performs just in time compilation producing executable machine readable code and also handles garbage collection and other tasks The key point is that the CIL code compiled from C conforms to the Common Type Specification CTS and can interact with code that was generated from the NET versions of Visual Basic Visual C or any other CTS compliant language 13 2 2 UlProtocol This chapter introduces the reader to the UlProtocol its architecture and communica tion between UIP client and server 2 2 1 About UIProtocol Universal Interface Protocol UIProtocol UIP is a user interface specification language 14 being developed at FEE CTU for research purposes At the time of writing the specification is not publicly available UIProtocol provides means for describing user interfaces and transferring data related to interaction between user and an UIProtocol based application It is designed to be cross platform programming language indepen dent and easily localized 14 The goal of UIProtocol is to simplify development for various target platforms with UlProtocol a developer only h
58. p subject text Message amp message text speak punctu ation Send email to Hugh Briss subject new shoes message I can t wait to show you my new shoes period Note to self Message text Note to self milk remember the Set alarm Time or for amp time such Set alarm for 7 45 p m label as 10 45 a m or 20 minutes switch the laundry from now Label amp name of alarm Call The name of one of your con Call George Smith tacts 39 Appendix B User Manual Running the developed solution is simple Open the WP8uip sln file in Visual Studio and install in on your Windows Phone 8 device Alternatively you can also run it in an emulator Run the UIP server and connect to it by providing the client with server s IP address After connecting you can browse through the application freely B 1 Contents of the Attached CD E AAA da C sources A as o es ol o the thesis text directory A A A E o baky the TFX sources 40 Bibliography 10 11 12 13 14 David N Hyerle Visual Tools for Constructing Knowledge 1996 Visual impairment and blindness 2013 URL http www who int mediacentre factsheets fs282 en visited on 05 11 2014 An Aging Nation The Older Population in the United States 2014 URL http www census gov prod 2014pubs p25 1140 pdf visited on 05 11 2014 NaviTerier navigation system in buildings for the vi
59. port 3 the number of elderly people citizens 65 years old and older in the United States is expected to double within the next four decades making up 21 of the US population The data show that the target group for an indoor navigation system is growing and technologies that assist with indoor navigation will become of greater importance To help tackling the problem there has been a number of research projects proposing solutions to indoor navigation of visually or motor impaired or elderly see section 2 4 One such project focused on visually impaired called NaviTerier 4 is being developed at FEE CTU The project described in greater detail in section 2 4 is intended to run on a handheld device a smartphone and works on the principle of sequential presentation of carefully prepared descriptions of the building segments to the user 1 Introduction by means of mobile phone voice output NaviTerier has been brought together with UIProtocol UIP another research project of FEE CTU whose goal is to create an platform indpendent UI description language and which is described in greater detail in the next chapter NaviTerier and UIP are being integrated to form NUIP which combines the naviga tional part of NaviTerier and UI generator running under UIP Server 5 NUIP consist of several sub systems firstly there is a route planner which supports customizing of the route according to the user abilities and preferences Secondly a nav
60. r font size settings It also offers a built in screen reader called TalkBack Android aims to be usable even for visually impaired 2 3 3 iOS Accessibility This chapter covers the accessibility of Apple s iOS Again we consider the latest iOS released at the time of writing which is version 7 0 4 Overall the accessibility features 12 2 3 Accessibility of Current Mobile Platforms of iOS are very similar to those of Android and therefore we will describe them more briefly Speech Features As with the previous two platforms iOS also offers users to interact with a device using speech iOS supports speech recognition and text to speech in 15 major languages the same number as Windows Phone 8 iOS also comes with a number of built in voice commands 27 but does not allow developers to expose their own Speech Recognition Dictation Users can give input to an app or accomplish tasks with it using speech recognition An example usage can be dictating content of a text As mentioned above this feature supports 15 languages and reguires an internet connection Voice Control Siri Siri in iOS can be thought of as an equivalent to Android s Google Now Siri can send emails set reminders and more 27 If asked a guestion it can read aloud the answer Text to Speech TTS TTS can be used to speak text to the user via the phone s speaker or headset and this feature was added only recently in iOS 7 0 The spoken text can be
61. r s cane position using triangulation The information from Wiimote units is communicated via Bluetooth to a computer which computes the position and then sends the directions to the user s smartphone via wifi The distance limit of 10 m imposed by Bluetooth can be extended by using wifi but the authors do not consider this relevant because the proposal is in a preliminary evaluation phase TTS engine running on the phone converts the directions to speech The system has undergone preliminary testing with two blind and seven blindfolded users and the authors claim that Results show that blind and blindfolded people im proved their walking speed when the navigation system was used which indicates the system was useful 2 4 8 Other There are also research works in the fields of robotics and artificial intelligence that study the problem of navigation More specifically they tackle the problem of real time indoor location recognition 35 36 37 Some of these solutions allow for creating a reference map dynamically Even though they proved to be useful in the domain of robotics and automotive industry their applications to navigating people are limited as they require expensive sensors and powerful computing resources Wearing these devices would make the traveling of the users more difficult and limited For these reasons the solution proposed by Hesch and Roumeliotis 38 is interesting because they integrated these devices apart from t
62. received from the server This data is forwarded to it from the SocketWorker instance SocketWorker is the low level socket communication class which sends events to the server It also runs an instance of BackgroundWorker class which in an extra thread awaits data from the server The reason there is a separate thread for receiving data is that we cannot make any assumptions about when the server will send data to the client Generally speaking server can decide to send model updates at any time not only as a response to a certain user action 4 0 17 Model Updates and Binding Any property of UIP document can instead of direct value contain a reference to a model and its property as described in 2 2 3 As an example let us consider a button The text displayed in the button its Content can be either hard coded into the UIP document or there can be a reference to a model property If the reference is present the ModelManager looks into an internally stored dictionary of models and if the model is present the value of its corresponding property is immediately used If that is not the case ModelManager makes a request for the model and once it arrives its corresponding property s value is used In both cases a binding is created so that the future updates of the model property are correctly propagated throughout the application The ModelManager class only needs to be instantiated once so that the application state is stored in one
63. rst issue was related to receiving communication from the server The difficulty was that the model updates can arrive at any time not only as a response to a certain user action The problem was solved by running the receive operation in an extra thread This way the client socket is always ready to receive data Another issue was related to chained UIP properties The UIP properties are tran sitive consider property A whose key refers to property B Property B also has a key which points to property C Property C contains a constant value The constant has to be propagated back to properties A and B Also when property C is updated the update has to be reflected in properties A B A simple solution would be to create a cus tom DependencyProperty and then create a binding However we were unable to create the chained binding and chose an alternative way instead The solution involves creating event listeners In the example given above the property B would create an event handler that would hook up on changes in C s value Similarly property A would be listening for updates of B Next rendering containers of the class public scroll into grid layout created unnecessary top and left margins of the container These margins were removed by set ting the VerticalAlignmentProperty and HorizontalAlignmentProperty so that UI controls in grid align in the direction of the top left corner Unfortunately some of the native UI control classes inherit
64. s a real windows core 12975 visited on 04 04 2014 Windows Phone 8 and Windows 8 platform comparison 2012 URL http msdn microsoft com en us library windowsphone develop 33681690 v vs 105 aspx visited on 04 04 2014 C Sharp Language Specification 2002 URL http download microsoft com download a 9 e a9e229b9 fee5 4c3e 8476 917dee385062 CSharp 20Language 20Specification 20v1 0 doc visited on 04 01 2014 Introduction to the C Language and the NET Framework 2014 URL http msdn microsoft com en us library z1zx9t92 aspx visited on 05 07 2014 V et al Slovacek UIProtocol specification draft 8 In CTU in Prague 2010 4 Bibliography 15 23 24 25 26 27 28 29 42 Speech for Windows Phone 8 Speech for Windows Phone 8 development center 2014 URL http msdn microsoft com en us library windowsphone develop 43206958 v vs 105 aspx visited on 01 01 2014 Voice commands for Windows Phone 8 2014 URL http msdn microsoft com en us library windowsphone develop 33206959 v vs 105 aspx visited on 01 04 2014 Meeting requirements for accessible text XAML 2014 URL http msdn microsoft com en us library windows apps hh868163 aspx vis ited on 05 06 2014 Accessibility on your phone 2014 URL http www windowsphone com en ZA how to wp8 settings and personalization accessibility on my phone visited on
65. s processing location data and more Therefore there is also more potential for code reuse Furthermore Windows Phone 8 and Windows 8 share the same NET engine 11 This is to deliver more stability and performance to the apps and improve battery life Most new devices are now dual or quad core and the operating system and apps are expected to run faster thanks to this 11 The development for Windows Phone 8 is supported by Visual Studio 2013 IDE 2 1 1 About C and NET Framework C is a multi paradigm programming language encompassing strong typing impera tive declarative functional generic object oriented and component oriented program ming disciplines 12 It was developed by Microsoft within its NET initiative and its first version was released in 2002 12 The latest release at the time of writing is C 5 0 C was developed at Microsoft by a team led by Anders Hejlsberg and was inspired by the C programming language NET Framework is a part of Windows OS which provides an virtual execution system called common language runtime CLR and also includes an extensive set of classes 2 2 UIProtocol and libraries that offer a wide range of functionality 13 The specification called the Common Language Infrastructure CLI is an international standard by ISO IEC 23270 2006 and ECMA 334 which specifies execution and development environment that allows multiple high level languages to be used on different computer platf
66. s for indoor navigation based on various technologies One of such projects is NUIP from FEE CTU which combines NaviTerier path planner and directions generator with UlProtocol We analyzed the state of the art in indoor navigation and compared the accessibility features of the most common smartphone platforms The reader was also introduced to UIProtocol its architecture and how it functions The goal of the thesis was to implement an UlProtocol client supporting the basic UIP features The platform of development was chosen to be Windows Phone 8 The client was expected to be able to be used within the NUIP project and consequently we researched ways of making it accessible to people with special needs We found however that the Windows Phone 8 platform is not very friendly toward visually impaired Yet the developed client remains a functional UIP client for the Windows Phone 8 platform 6 1 Current Features Within the bachelor thesis we successfully implemented a basic UlProtocol client which implements e Basic Ul controls e Binding and model wide binding e Graceful degradation of unsupported elements e Support for interpolated model updates animations e Support for absolute and grid layouts and scrollable containers e Support for styling background color font size and font color The features we implemented completely cover the functional requirements we have set in the Design chapter with the exception of Ul generator A
67. simple strings The industry standard Speech Synthesis Markup Language SSML is not mentioned in the API documentation Other Speech Features iOS comes with a screen reader called VoiceOver Google s TalkBack is very similar to it VoiceOver offers very similar functions and allows reading the content of the screen based on touch input and controlling the device by gestures 28 The mentioned blog post of the blind accessibility engineer from Mozilla Founda tion favors VoiceOver over TalkBack 26 Other Tools for Ease of Access iOS too comes with more features for ease of access which can help lightly visually impaired users The user can change font size invert colors and use the screen magnifier Zoom 27 iOS devices also support a number of Bluetooth wireless braille displays out of the box 27 User can pair their braille display with the device and start using it to navigate it with VoiceOver iPad iPhone and iPod touch include braille tables for more than 25 languages Moreover iOS offers compatibility with hearing aid devices Conclusions Apple s iOS was the first to offer advanced accessibility features and the first to become usable for visually impaired users Of all analyzed platforms iOS offers the widest accessibility feature set iOS allows developers to create apps accessible for a range of users 2 3 4 Comparison of Analyzed Platforms A quick overview of the accessibility features of the three most common mob
68. stion for visually impaired users The platform has recently been experiencing growth of about 6 in some countries of Europe but only slow growth in others 21 With the Windows Phone 8 1 update there is a new screen reader feature included but it has not been out only for a short time and thus we cannot make any conclusions about its usefulness It should be noted that the other two major platforms iOS and Android both include a screen reader 2 3 2 Android Accessibility Similarly to the previous section here we will analyze the accessibility options for devices running the Android operating system The analysis covers the features of the latest Android OS released at the time of writing which is version 4 4 code name KitKat It should be noted that there were no major updates to the accessibility options since Android 4 2 2 Jelly Bean Speech Features Similarly to WP8 Android also offers the option to interact with the device using speech and has some interesting accessibility features Compared to Windows Phone 8 Android offers a wider language support Similarly to WP8 an Android developer can take advantage of speech recognition and text to speech TTS Android comes with a number of built in voice commands but unlike the Windows Phone Android does not allow developers to expose their own voice commands The last important feature on Android is the TalkBack screen reader At the time of writing the speech recognition supports
69. sually impaired 2013 URL http usability felk cvut cz naviterier visited on 01 01 2014 Zdenek Mikovec Jan Balata Miroslav Macik Context Sensitive Navigation in Hospitals In 30th Annual International IEEE EMBS Conference 2013 Miroslav Macik et al Platform Aware Rich Form Generation for Adaptive Sys tems through Code Inspection In Human Factors in Computing and Infor matics Ed by Andreas Holzinger et al Vol 7946 Lecture Notes in Computer Science Springer Berlin Heidelberg 2013 pp 768 784 ISBN 978 3 642 39061 6 DOI 10 1007 978 3 642 39062 3_55 URL http dx doi org 10 1007 978 3 642 39062 3_55 Cisco Visual Networking Index Global Mobile Data Traffic Forecast Update 2013 2018 2014 URL http www cisco com c en us solutions collateral service provider visual networking index vni white_paper_ c11 520862 html visited on 05 14 2014 Android and OS Continue to Dominate the Worldwide Smartphone Market with Android Shipments Just Shy of 800 Million in 2013 2014 URL http www idc com getdoc jsp containerId prUS24676414 visited on 05 06 2014 Despite a Strong 2015 Worldwide Smartphone Growth Expected to Slow to Sin gle Digits by 2017 2014 URL http www idc com getdoc jsp containerId prUS24701614 visited on 05 20 2014 Microsoft s Windows Phone 8 finally gets a real Windows core 2012 URL http www zdnet com blog microsoft microsofts windows phone 8 finally get
70. t are provided by the operating system is listed in table 10 Appendix A A developer can also define her own set of voice commands and allow users to carry out more advanced tasks within the app 16 This is important for our work since it allows for exposing a wider range of commands to potential visually impaired users Note that technically this still happens from the outside of the app as described in the previous paragraph Text to Speech TTS TTS can be used to speak the application content text only to the user via the phone s speaker or headset The spoken text can be simple strings or strings formatted according to the industry standard Speech Synthesis Markup Lan guage SSML Version 1 0 15 TTS is also used in some of the other features for ease of access which are covered in the next paragraph Other Speech Features A feature named Speech for phone accessibility allows the following 16 1 Talking caller ID When getting a call or receiving a text the phone can announce the name of the caller or the number 2 Speech controlled speed dial User can assign a number to a person from the contact list and then say Call speed dial number where number is the assigned number to call the person Assigning the speed dial number is also speech enabled 3 Read aloud incoming text messages 10 2 3 Accessibility of Current Mobile Platforms Other Tools for Ease of Access Windows Phone 8 comes with more features for ease o
71. tion and unit tests 1 3 Document Outline The document has five more chapters Chapter 2 Analysis Contains an analysis which was carried out before the development The analysis covers the UIProtocol itself discusses the accessibility of today s smartphone plat forms shows other projects in the field of indoor navigation and shortly explains the accessibility guidelines for WP8 development Chapter 3 Design The chapter goes through the design of the UIProtocol client We cover the out comes of the analysis reguirements for the app and how we designed the application architecture Several class diagrams are included Chapter 4 Implementation Establishing upon the design the fourth chapter covers the implementation of the UlProtocol client problems encountered during the development and how they were solved Chapter 5 Testing To finish the development cycle testing of the developed application is needed For 1 3 Document Outline that purpose a testing application and unit tests were developed This chapter covers the results of testing Chapter 6 Conclusions and Future Work The last chapter discusses the conclusions and future work 2 Analysis Mobile devices and technologies play an important role in today s everyday life The number of mobile phones tablets and other handheld devices has been increasing and according to a report by Cisco 7 the number of mobile connected devices will exceed the number of p
72. tion describes the design of several sub systems which are responsible for handling the communication models events inner representation of the UI elements their rendering and more The chapter contains several UML diagrams Note that most of them are simplified Even though there are existing implementations of UIProtocol client the design of this one was not influenced by any of them 3 0 1 Requirements The client application will be developed and run on a Windows Phone 8 device Since the entire user interfaces and information about events is intended to be transferred over wireless internet connection there will be a delay present in the application s reaction time which is a inescapable consequence of the client server architecture The delay should be reasonably small to allow for a comfortable usage of the application Even with this delay the application should perform well in terms of UI rendering times reaction time and overall feel There is a number of requirements an app should meet in order to be truly accessible In our analysis we found that the support of Windows Phone 8 for accessibility is lower than at the competing platforms Namely support for a key accessibility feature the screen reader is not present by default This can be a major flaw to the application accessibility especially for visually impaired who would have to use a third party screen reader in order to be able to navigate through the app We ma
73. tional org publications standards Ecma 334 htm 3Mono Framework http www mono project com Main Page 1DotGNU Portable NET http www gnu org software dotgnu pnet html 2 Analysis Client Server Event jr m fo o Inter Layer Bop Action Figure 1 the client server architecture of UIP taken from 14 Let us give an example of when an event is sent to the server Consider a situation when a user requests a weather app to his device As he enters his location and presses a button to request the weather information part of the job is done directly by the client and the other part is sent to the server The part done directly at the client are easy tasks such as visual effects when pressing the button The request for weather information is then sent to the server Server processes the request and responds by sending the interface structure information UI components description and the weather data This is displayed to the user who then has other options to interact with the app The documents of UIProtocol can be sent in either direction usually through a single channel without waiting for a request i e the server can send updates to the client as soon as the displayed information needs to be updated without waiting for an update request Should there be such need there is the possibility of both client and server running on the same machine although this is not a typical usage UIProtocol Client UlProtocol client is thi
74. uired interfaces and not execute any code on that data The data shown to the user can be either constant or come from models which are designed to be a data storage as discussed in 2 2 3 Models will be managed by one instance of ModelManager class If an UIP element has a property that refers to a model ModelManager will be responsible for reguesting the model containing this property Once the model is re ceived ModelManager will store all its properties and will manage future model up dates Note that the updates can come from the server at any time ModelManager will also need a reference to InterfaceManager because server s models can contain a reguest to render an interface The relationship between classes that are involved in model management is shown in figure 5 When a UIP property refers to a model a binding will be created so that when the UIP property is updated the update is shown in the UI For that reason there has to be a data binding between the two We will make use of the data binding API which is built in to the Windows Phone platform class Model interfaceManager InterfaceManager _mm ModelManager models Dictionary lt string Model gt AddOrUpdateModelPro A perty ModelProperty void _requestedModels HashSet lt string gt GetModelProperty string ModelProperty AddModels XDocument List lt string gt CheckKeysAndinterpolation void GetModel string Task lt Model gt Model string string
75. y propose some new features that could be implemented by UIProtocol to increase its own support for accessibility At any rate even with the Windows Phone 8 platform s low accessibility support the developed app will remain a functional UIP client capable of handling valid UIP documents Summary of Requirements We have developed the following lists of non functional and functional requirements respectively Non functional requirements e UI components have platform native look e Client app will be will be written in C e The client should not use much phone resources when idle Windows Phone 8 1 users may use the Narrator feature 20 App should be stable and able to process valid UIP documents Compatibility with UIP specification draft 8 Ability to run on any WP8 device UI loading times below 0 5 s for UIs of usual size with stable internet connections Functional requirements e Support for basic user interface elements Graceful degradation for unsupported elements Support for binding and model wide binding Support for interpolated model updates animations Support for UI generator API Support for Events Support for absolute and grid layouts Support for styling font size colors etc 3 0 2 Client server Communication The client will communicate with the server over TCP connection which will be handled by a standard socket Upon this communication channel UIProtocol XML files will be transferred Once the client
76. yst my jeho c lem je usnadnit navigaci posti en ch u ivatel uvnit budov Tato pr ce se proto zab v i zp soby jak zv it p stupnost aplikace pro hendikepovan u ivatele nap klad zrakov posti en Klient mus b t schopen prov d t standardn kony jako komunikace se serverem vykreslov n u ivatelsk ch rozhran obsluha akc u ivatele a dal Kl ov slova Navigace Generov n UI P stupnost Windows Phone 8 UIProtocol C Abstract UlProtocol is a user interface specification language being developed at FEE CTU for research purposes It is designed as a client server system where the server runs an app and provides its user interface description to the client The client renders the user interface informs the server of user triggered events and processes the server response This work describes the development of an accessible UIProtocol client for Windows Phone 8 platform The client is developed as a part of a complex system for navigation of visually impaired inside buildings Therefore we also explore the possibilities of making the application more accessible to people with disabilities such as visually impaired The client application has to be able to perform standard operations such as communicating with the server rendering the user interfaces handling user actions and more Keywords Navigation UI Generation Accessibility Windows Phone 8 UIProtocol C Contents 1

Accessible UIP client for Windows Phone 8

Contents

Download Pdf Manuals

Related Search

Related Contents