Android Accessibility

Notes

• Explore by touch was added in Android 4.0

Techniques

Adding an accessibility label to an element

To add some text for an image, button or view set the android:contentDescription to the relevant view in your layout xml file

android:contentDescription="@string/logo_alt"

There is also a method for doing this

public void setContentDescription (CharSequence contentDescription)

If you have some furniture which doesn't require some text use @null so you don't get an error in link

android:contentDescription="@null"

• android:contentDescription
• [setContentDescription](http://developer.android.com/reference/android/view/View.html#setContentDescription(java.lang.CharSequence)
• Android Accessibility Solution in 30 Seconds - video by Ted Drake showing how to use contentDescription attribute

Making a view focusable

If a view is not focusable by default you can make it focusable from the XML layout file by setting the android:focusable attribute to "true"

android:focusable="true"

There are also a methods for doing this

setFocusable(boolean)
setFocusableInTouchMode(boolean)

• android:focusable
• setFocusable
• attr_android:focusableInTouchMode
• setFocusableInTouchMode

Controlling focus order

You can provide explicit overrides to the ordering using the following XML attributes in the layout file

• android:nextFocusDown - Defines the next view to receive focus when the user navigates down.
• android:nextFocusLeft - Defines the next view to receive focus when the user navigates left.
• android:nextFocusRight - Defines the next view to receive focus when the user navigates right.
• android:nextFocusUp - Defines the next view to receive focus when the user navigates up.

For more detail see: Controlling focus order

Speak information to a user

announceForAccessibility(CharSequence)

h2. How do you do these?

1. Set a trait such as selected
2. Move focus to an element
3. Group content description on a container
4. Use a list so that a user knows how many items there are
5. How to navigate an application using directional control - e.g the D-pad

Resources

Google Documentation

• Android Design: Accessibility
• API Guide - Accessibility | developer.android.com
  • Making Applications Accessible
  • Accessibility Developer Checklist
  • Building Accessibility Services
• Implementing Accessibility | Training
  • Developing Accessible Applications
  • Developing an Accessibility Service
• Accessibility Testing Checklist
• android.view.accessibility
  • AccessibilityEvent
  • AccessibilityEventSource

Forums

• eyes-free

Articles

• Take These Steps to Make your Android App Accessible
• Vodaphone Developers Blog: Designing for Accessibility (Android)
• Making Android apps voice output accessible - by Henny Swan
• Android Developers Blog: Accessibility: Are You Serving All Your Users?
• Implementing Accessibility on Android
• Top 7 Android Accessibility Features

Blogs

• Android developers blog - tag:accessibility
• Henny Swan bog - tag:android
• Eyes-Free Android

Presentations / Slides

• TalkBack & Magnification Accessibility in Android 4.2+
• Leveraging Android Accessibility APIs To Create An Accessible Experience

Videos

• YouTube Channel: EyesFreeAndriod
• Google I/O 2011: Leveraging Android Accessibility APIs To Create An Accessible Experience
• Google I/O 2012 - Making Android Apps Accessible
• Developing with Accessibility - 2 day event

Misc

• Android Accessibility | http://eyes-free.googlecode.com/
• apps4android