Notifying an assistive technology application when the UI changes

You can enable a BlackBerry® device application that uses custom UI components to send information to an assistive technology application by using the the net.rim.device.api.ui.accessibility package. When a custom UI component changes, an assistive technology application receives a notification about the change and can retrieve more information about the change from the custom UI component.

The notification about the change contains the following information:
  • name of the custom UI component
  • type of event, for example, the contents of the custom UI component changing or the custom UI component getting focus
  • value of the custom UI component before the event
  • value of the custom UI component after the event

For example, consider a BlackBerry device application that uses a custom class called myTextField that extends the TextField class. When a BlackBerry device user changes the text in a myTextField instance, an assistive technology application receives a notification and retrieves information about the text that the user changed.


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