Android - Inactivity/Activity regardless of top app

Question

I need to find out when the last user interaction was, regardless of which application is on top. I don't care about where or what the event was I just need to know when it was. Or alternatively, as it happens, I receive an event.

I've tried multiple things:

1. Create service with a window and added a touch listener. This ate the touch event and didn't pass it down
2. Looked for a shell command. getevent works (new line comes in every time a touch is received) however you need root and so it is not an appropriate solution for me.
3. Looked for "time until lock" but came up with nothing.

Also note: There is no security concern with this as I don't need any identifying information such as touch location. Just a type stamp (or live event).

I'm open to using reflection to figure it out as well.

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@user2558882 has a very good solution. As of now, that's the best approach I've come across.

While that's great, it still requires the user to manually enable our application in the accessibility controls. We have customers with thousands of devices and we have a way to automatically update and change settings. We try and keep manual configuration to a minimum, but some things still require user input such as enabling Device Admin mode. So this solution is acceptable however I'm still open to a way that doesn't require any user input to enable.

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I ended up implementing @user2558882's idea to use an accessibility service. Though other ideas are welcome.

Answer 1

This is just an idea, and may not be fully transferable.

Here's what an AccessibilityService can do:

An accessibility service runs in the background and receives callbacks by the system when AccessibilityEvents are fired. Such events denote some state transition in the user interface, for example, the focus has changed, a button has been clicked, etc.

You will be informed of the event inside onAccessibilityEvent(AccessibilityEvent):

@Override
public void onAccessibilityEvent(AccessibilityEvent event) {

    // Some event

    timeSinceLastInteraction = System.currentTimeMillis();

}

You could periodically log the updates:

Log.i("LOG_TIME_ELAPSED", "Last user interaction was " + 
             ((System.currentTimeMillis() - timeSinceLastInteraction) / 1000) + 
                      " seconds ago.");

There are two ways in which you can configure your AccessibilityService:

1. In code, inside onServiceConnected(). (API 4 onwards)

2. In xml, using the meta-data tag in your service. (API 14 onwards)

In your application's case, you could probably set AccessibilityServiceInfo.eventTypes to:

accessibilitySeviceInfo.eventTypes = AccessibilityEvent.TYPES_ALL_MASK;

But, TYPES_ALL_MASK will include notifications such as: AccessibilityEvent.TYPE_ANNOUNCEMENT, AccessibilityEvent.TYPE_NOTIFICATION_STATE_CHANGED etc. which I am guessing you do not care to intercept. So, you'll need to choose a subset of AccessibilityEvent.TYPE_X.

Another thing you should be careful about is the notification timeout:

The timeout after the most recent event of a given type before an AccessibilityService is notified.

The event notification timeout is useful to avoid propagating events to the client too frequently since this is accomplished via an expensive interprocess call. One can think of the timeout as a criteria to determine when event generation has settled down.

So, be generous with the timeout value.

You'll find this page very helpful in case you decide to go with the AccessibilityService option: Developing an Accessibility Service.

From your comments to Chloe's answer, it seems that the device is under your control: meaning, to some extent, you don't have to rely on the user for enabling the service:

The lifecycle of an accessibility service is managed exclusively by the system and follows the established service life cycle. Additionally, starting or stopping an accessibility service is triggered exclusively by an explicit user action through enabling or disabling it in the device settings.

You can enable the AccessibilityService at time of deployment, and perhaps restrict access to Settings menu using an app like AppLock.

Another option is to check whether your AccessibilityService is enabled from time to time:

AccessibilityManager am = (AccessibilityManager)
                               getSystemService(ACCESSIBILITY_SERVICE);

List<AccessibilityServiceInfo> listOfServices = 
                             am.getEnabledAccessibilityServiceList(
                               AccessibilityServiceInfo.FEEDBACK_ALL_MASK);

for (AccessibilityServiceInfo asi : listOfServices) {

    // Check if your AccessibilityService is running

}

In case the AccessibilityService has been disabled by a inquisitive/notorious user, you can lock the device by displaying a fullscreen view with text: Device has been locked. Contact a Sales Rep to unlock this device.

Answer 2

I believe you have to return false to indicate that your transparent service window did not consume the touch event. That way the event loop will pass it down the stack to the lower windows.

https://developer.android.com/reference/android/view/View.OnTouchListener.html

Another possibility, is to add a service which listens for motion/accelerometer events.

https://developer.android.com/guide/topics/sensors/sensors_motion.html

Another possibility is to listen for ACTION_USER_PRESENT

https://developer.android.com/reference/android/content/Intent.html#ACTION_USER_PRESENT

or ACTION_SCREEN_ON

https://developer.android.com/reference/android/content/Intent.html#ACTION_SCREEN_ON