No callbacks from AccessibilityService on locked Android

Question

Next code stopped working in Android 8.1 when smartphone is locked (display is black)

it only works if phone is unlocked

In Android 8.0 I remember next code was working always

<service
    android:label="@string/accessibility_service_name"
    android:name=".WindowChangeDetectingService"
    android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE">
    <intent-filter>
        <action android:name="android.accessibilityservice.AccessibilityService"/>
    </intent-filter>
    <meta-data
        android:name="android.accessibilityservice"
        android:resource="@xml/accessibilityservice"/>
</service>

My AccessibilityService class

public class WindowChangeDetectingService extends AccessibilityService {

    @Override
    protected void onServiceConnected() {
        super.onServiceConnected();

        //Configure these here for compatibility with API 13 and below.
        AccessibilityServiceInfo config = new AccessibilityServiceInfo();
        config.eventTypes = AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED;
        config.feedbackType = AccessibilityServiceInfo.FEEDBACK_GENERIC;
        config.flags = AccessibilityServiceInfo.FLAG_INCLUDE_NOT_IMPORTANT_VIEWS;

        setServiceInfo(config);
    }

    @Override
    public void onAccessibilityEvent(AccessibilityEvent event) {
        if (event.getEventType() == AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED) {
            if (event.getPackageName() != null && event.getClassName() != null) {
                ComponentName componentName = new ComponentName(
                        event.getPackageName().toString(),
                        event.getClassName().toString()
                );
                Log.i("Component", componentName.flattenToShortString() + " " + componentName.getShortClassName());
            }
        }
    }

UPDATE

Cause such feature I need only for my phone I found next solution:

Options / Security & Location / Screen lock / None

(Select None)

`onAccessibilityEvent` isn't calledm it's only called if Phone display is active (not black) — user155, Jul 24 '18 at 06:05
@Khemraj when I press power button and phone's display becomes black (phone is locked) then it stops working and `onAccessibilityEvent` is never called — user155, Jul 24 '18 at 06:07
@Khemraj I selected **None** for **Screen lock** (`Options / Security & Location / Screen lock / None`) seems it works ok even if phone's display is turned off (black) — user155, Jul 24 '18 at 06:14

score 0 · Answer 1 · answered Jul 24 '18 at 06:20

0

Perhaps your Service is being killed by OS due to Doze mode or Standby.

In Doze mode, the system attempts to conserve battery by restricting apps' access to network and CPU-intensive services.

Now as solution for this you can check periodically (say by 2 hours) if your service is killed. Implement periodic task by WorkManager. And restart service if killed.

answered Jul 24 '18 at 06:20

Khemraj Sharma

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` check periodically (say by 2 hours)` - what do you mean? it's killed instantly after pressing power button (to lock phone) – user155 Jul 24 '18 at 06:26
See work manager link, you have to make another scheduler to check Accessibility service. – Khemraj Sharma Jul 24 '18 at 06:49

No callbacks from AccessibilityService on locked Android

1 Answers1