Developer tool for creating accessible GUIs in Android mobile OS

Paperback – October 2011

1. Android accessibility overview (I)

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• Android OS Accessibility

– Accessibility API quite powerful

• Widgets containing states and meta information

• Accessibility services and events

– Multilingual TTS

– Haptic (Vibration)

– Sounds

– Insufficent system-level accessibility

• Mechanisms provided are not enough

• Big problem!

2. Android accessibility overview (II)

• Some conclussions

– Expensive developements

• More requistes

• More money and time

– Leads into fragmentation

• “Each developer , each Look&Feel”

– Trouble to developers

• Small targetting & Big effort Low interest

2. Android accessibility overview (Ii)

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3. Solving problems

• Provide accessible resources

– Avoiding trouble

• Accessible applications by default

• Hiding complexity to developers (total transparency)

• Without regarding on resources or requirements

– Maximizing compatibility

• Working from 1.6 to current Android version

• No kernel modifications or root required

– Flexible + Scalable + Extendable + Customizable

– Enhancing Android’s native accessibility

Android accessibility framework

3. Solving problems

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4. Accessibility framework – Accessibility service

• Accessible service

– Integrated with the Android OS • Operating on user’s demand (settings)

– Accessible backend • Shared by all the applications using the framework

• Working in background as follows:

4. Framework – Accessibility service

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4. Accessibility framework – Widgets

• Widget accessible behaviour extension

– Relying on accessible containers

– TTS based feedback for blind users

• New accessible components

– Calendar, charts, switch… and so on

4. Framework – Accessible widgets

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5. Accessibility framework – Containers

• Set of accessible layouts

– Extending Android’s default layouts

– Different layouts for different solutions

• Enhancing Android accessibility

– Screen reading

– Main behaviour

• The selected components are remarked

• For each selected component, its information is secuentially spoken

5. Accessible containers

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5. Accessibility framework – Containers (II)

– User touch inputs • Selects the complete layout or just the tapped component

• One tap selects, another confirms action

– User trackball motions • Allows screen navigation

• Each motion selects the next component in the target direction

• Clicking the trackball perform action

– Gesture navigation • Allows screen navigation with simple gestures

5. Accessible containers (II)

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5. Accessibility framework – Containers (III)

• Containers overview and gestures sample

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5. Accessible containers (III)

6. Use case

• A developer has created a very nice application

• He wants to turn it accessible

– In short time

– In a cheap way

• He just

– Adds the resources and libraries provided to his WS

– Locates the GUI XMLs and their source code

• Changes the default layouts for the accessible ones

– May need to refactor the xml

• Links the program and gestures functionallity (2 single LOCs)

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6. Use case

7. Accessibility framework – GUIs design assistant

• Tool for create GUIs

– Branch of the original DroidDraw tool

– Helps developers to create GUI

• Integrating the accessible components and layouts

• Generating the XML files

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7. GUIs Assistant

7. Accessibility framework – GUIs design assistant

Thank you for your time

Please suggest and ask

End of presentation