onKeyEvent & Accessibility Service

Question

My users will be using TalkBack enabled or some other Accessible Service. I would like to capture the onKeyEvent events in our App but the event is dispatched to the enabled Accessibility Services. I have created the following basic Accessibility Service.

public class Accessibility_Service extends AccessibilityService {

    private String TAG = Accessibility_Service.class.getSimpleName();

    @Override
    public boolean onKeyEvent(KeyEvent event) {
        int action = event.getAction();
        int keyCode = event.getKeyCode();
        if (action == KeyEvent.ACTION_UP) {
            if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
                Log.d("Hello", "KeyUp");
            } else if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
                Log.d("Hello", "KeyDown");
            }
            return true;
        } else {
            return super.onKeyEvent(event);
        }
    }

    /**
     * Passes information to AccessibilityServiceInfo.
     */
    @Override
    public void onServiceConnected() {
        Log.v(TAG, "on Service Connected");
        AccessibilityServiceInfo info = new AccessibilityServiceInfo();
        info.packageNames = new String[] { "com.camacc" };
        info.eventTypes = AccessibilityEvent.TYPES_ALL_MASK;
        info.notificationTimeout = 100;
        info.feedbackType = AccessibilityServiceInfo.FEEDBACK_SPOKEN;
        setServiceInfo(info);

    }// end onServiceConnected

    /**
     * Called on an interrupt.
     */
    @Override
    public void onInterrupt() {
        Log.v(TAG, "***** onInterrupt");

    }// end onInterrupt

    @Override
    public void onAccessibilityEvent(AccessibilityEvent event) {
        // TODO Auto-generated method stub

    }
}// end Accessibility_Service class

When I check the logcat I am getting no response. Is it possible to consume the Volume Down and Up Events prior to TalkBack or other such Accessibility Services?

Thank you.

EDIT:

ADDED THE FOLLOWING FLAG STILL WITH NO LUCK:

info.flags = AccessibilityServiceInfo.FLAG_REQUEST_FILTER_KEY_EVENTS;

Answer 1

Try to configure the Accessibility Service like this in the xml resource, if you need more information look this: https://developer.android.com/guide/topics/ui/accessibility/services.html

<?xml version="1.0" encoding="utf-8"?>
<accessibility-service
xmlns:android="http://schemas.android.com/apk/res/android"
android:accessibilityEventTypes="typeContextClicked|typeViewClicked"
android:packageNames="com.example.andres.eventcapture"
android:accessibilityFlags="flagRequestFilterKeyEvents"
android:accessibilityFeedbackType="feedbackAllMask"
android:notificationTimeout="50"
android:canRetrieveWindowContent="true"
android:settingsActivity=""
android:canRequestFilterKeyEvents="true"
/>

It worked good!

Answer 2

Old question, but maybe this answer will help someone.

Yes, it's possible that another accessibility service consumes KeyEvent.

Please have a look at FLAG_REQUEST_FILTER_KEY_EVENTS documentation, there is: Setting this flag does not guarantee that this service will filter key events since only one service can do so at any given time. This avoids user confusion due to behavior change in case different key filtering services are enabled. If there is already another key filtering service enabled, this one will not receive key events.

So another accessibility service can consume KeyEvents.