Android app start and end event

Question

I have an app which track user activity on app which include time etc, Now if user has opened the app, It will start an session and till user in this app , his session will continue, He can switch to multiple activity. Now meantime he switches to another app, His session logging should be stopped and written down to file

What I tried

I created one base activity and On resume event if counter is zero, I start session and increment counter and On stop event , i decrement counter and if counter is zero, I stop session

But this will not calculate actual problem of tracking as android doesn't stop activity as user switch to another app.

So is there any way to achieve such thing.

Additional:

If we can get whether app activity is active on screen so event can be used to start or end session.

Answer 1

1.Create a class named AppLifecycleTracker and paste this.

private class AppLifecycleTracker implements ActivityLifecycleCallbacks {
            private int numStarted = 0;
            private String TAG = "AppLifecycleTracker";


            private int numOfCreated = 0;

            @Override`enter code here`
            public void onActivityCreated(Activity activity, Bundle bundle) {
                if (numOfCreated == 0) {
                    Log.d(TAG, "onActivityCreated: app started");
                }
                numOfCreated++;
                Log.d(TAG, "onActivityCreated: " + numOfCreated);
            }

            @Override
            public void onActivityStarted(Activity activity) {
                if (numStarted == 0) {
                    // app went to foreground
                    Log.d(TAG, "onActivityStarted: foreground");

                }
                numStarted++;


            }

            @Override
            public void onActivityResumed(Activity activity) {

            }

            @Override
            public void onActivityPaused(Activity activity) {

            }

            @Override
            public void onActivityStopped(Activity activity) {
                numStarted--;
                if (numStarted == 0) {
                    // app went to background
                    Log.d(TAG, "onActivityStarted: background");

                }
            }

            @Override
            public void onActivitySaveInstanceState(Activity activity, Bundle bundle) {

            }

            @Override
            public void onActivityDestroyed(Activity activity) {
                numOfCreated--;
                Log.d(TAG, "onActivityDestroyed: " + numOfCreated);
            }
        }

* in onActivityCreate if numOfCreated = 0, then you can say app has started. * in onActivityDestroyed if numOfCreated = 0, then you can say app is closed.

2. Create a class extending Application, in onCreate, add this line

   registerActivityLifecycleCallbacks(new AppLifecycleTracker());

3. set application name as the Application class in manifest.xml

Thats it. You are good to go.

Answer 2

I can think of two ways of doing it:

Option 1:

You can create a service which scans for the current application on the foreground and see if it is your activity. Here is some code you can use, I took it from another answer:

There's an easy way of getting a list of running tasks from the ActivityManager service. You can request a maximum number of tasks running on the phone, and by default, the currently active task is returned first.

Once you have that you can get a ComponentName object by requesting the topActivity from your list.

Here's an example.

ActivityManager am = (ActivityManager) this.getSystemService(ACTIVITY_SERVICE);

     // get the info from the currently running task
     List< ActivityManager.RunningTaskInfo > taskInfo = am.getRunningTasks(1); 

     Log.d("topActivity", "CURRENT Activity ::"
             + taskInfo.get(0).topActivity.getClassName());

     ComponentName componentInfo = taskInfo.get(0).topActivity;
   componentInfo.getPackageName();

You will need the following permission on your manifest:

<uses-permission android:name="android.permission.GET_TASKS"/>

Link to the answer: Android: How can I get the current foreground activity (from a service)?

You can call this every one second or less to detect if your app is still active. Please note that it is a deprecated and is not recommended for using for this kind of things, according to official documentation:

getRunningTasks()

Note: this method is only intended for debugging and presenting task management user interfaces. This should never be used for core logic in an application, such as deciding between different behaviors based on the information found here. Such uses are not supported, and will likely break in the future. For example, if multiple applications can be actively running at the same time, assumptions made about the meaning of the data here for purposes of control flow will be incorrect.

---

Option 2:

The second option is to create a class that extends Application with a flag, for example isAppRunning, which will be true or false according if your application is on the foreground or not:

public class MyAppContext extends Application {

   public boolean isAppRunning = true;

   public void setIsAppRunning(boolean v){
      isAppRunning = v;
   }

   public boolean isAppRunning(){
      return isAppRunning;
   }

}

Then on your AndroidManifest.xml you have to add this class so it will be used when your application starts. Just add android:name=".MyAppContext" under the application tag:

<application
        android:name=".MyAppContext"

Now in every activity that you have you should override onResume() and onPause() and set the flag to the corresponding value:

class BaseActivity extends Activity {


    @Override
    protected void onResume() {
        super.onResume();
        ((MyAppContext)getApplication()).setIsAppRunning(true);
    }

    @Override
    protected void onPause() {
        ((MyAppContext)getApplication()).setIsAppRunning(false);
        super.onPause();
    }
}

On this way every time you start an Activity the value of isAppRunning in MyAppContext will be true, when you exit the Activity it will be false but if another Activity opens (for example if you pressed the back button so you are returning to the previous activity) the value will be immediately true again.

When you finally finish all your Activities none of the onResume() methods will be called and all the onPause() methods will be called so isAppRunning will be false and you know your Activity is no longer on the foreground.

So resuming, if isAppRunning is true your application is on the foreground (start the session tracking) otherwise it's gone (stop the session tracking). You can create a Timer in MyAppContext class to check the value of isAppRunning periodically, so it would be:

public class MyAppContext extends Application {

   public boolean isAppRunning = true;
   public final int timerRate = 500;    // Execute timer task every 500mS

   public void setIsAppRunning(boolean v){
      isAppRunning = v;
   }

   public boolean isAppRunning(){
      return isAppRunning;
   }

   @Override
   public void onCreate() {
      super.onCreate();
      Timer mTimer = new Timer();

      mTimer.scheduleAtFixedRate(new TimerTask() {
         @Override
         public void run() {
            if(isAppRunning) startSesionTracking();
            else stopSesionTracking();
         }
      }, 0, REFRESH_TIME);
   }

   private void startSesionTracking () { ... };
   private void stopSesionTracking () { ... };

}

You should modify timerRate according to the precision you want to get in your session tracking.