Determining the current foreground application fro

Question

I wish to have one application that runs in the background, which knows when any of the built-in applications (messaging, contacts, etc) is running.

So my questions are:

1. How I should run my application in the background.

2. How my background application can know what the application currently running in the foreground is.

Responses from folks with experience would be greatly appreciated.

Answer 1

For cases when we need to check from our own service/background-thread whether our app is in foreground or not. This is how I implemented it, and it works fine for me:

public class TestApplication extends Application implements Application.ActivityLifecycleCallbacks {

    public static WeakReference<Activity> foregroundActivityRef = null;

    @Override
    public void onActivityStarted(Activity activity) {
        foregroundActivityRef = new WeakReference<>(activity);
    }

    @Override
    public void onActivityStopped(Activity activity) {
        if (foregroundActivityRef != null && foregroundActivityRef.get() == activity) {
            foregroundActivityRef = null;
        }
    }

    // IMPLEMENT OTHER CALLBACK METHODS
}

Now to check from other classes, whether app is in foreground or not, simply call:

if(TestApplication.foregroundActivityRef!=null){
    // APP IS IN FOREGROUND!
    // We can also get the activity that is currently visible!
}

Answer 2

This worked for me. But it gives only the main menu name. That is if user has opened Settings --> Bluetooth --> Device Name screen, RunningAppProcessInfo calls it as just Settings. Not able to drill down furthur

ActivityManager activityManager = (ActivityManager) context.getSystemService( Context.ACTIVITY_SERVICE );
                PackageManager pm = context.getPackageManager();
                List<RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
                for(RunningAppProcessInfo appProcess : appProcesses) {              
                    if(appProcess.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                        CharSequence c = pm.getApplicationLabel(pm.getApplicationInfo(appProcess.processName, PackageManager.GET_META_DATA));
                        Log.i("Foreground App", "package: " + appProcess.processName + " App: " + c.toString());
                    }               
                }

Answer 3

The ActivityManager class is the appropriate tool to see which processes are running.

To run in the background, you typically want to use a Service.

Answer 4

This is how I am checking if my app is in foreground. Note I am using AsyncTask as suggested by official Android documentation.`

`

    private class CheckIfForeground extends AsyncTask<Void, Void, Void> {
    @Override
    protected Void doInBackground(Void... voids) {

        ActivityManager activityManager = (ActivityManager) mContext.getSystemService(Context.ACTIVITY_SERVICE);
        List<ActivityManager.RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
        for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
            if (appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                Log.i("Foreground App", appProcess.processName);

                if (mContext.getPackageName().equalsIgnoreCase(appProcess.processName)) {
                    Log.i(Constants.TAG, "foreground true:" + appProcess.processName);
                    foreground = true;
                    // close_app();
                }
            }
        }
        Log.d(Constants.TAG, "foreground value:" + foreground);
        if (foreground) {
            foreground = false;
            close_app();
            Log.i(Constants.TAG, "Close App and start Activity:");

        } else {
            //if not foreground
            close_app();
            foreground = false;
            Log.i(Constants.TAG, "Close App");

        }

        return null;
    }
}

and execute AsyncTask like this. new CheckIfForeground().execute();

Answer 5

Do something like this:

int showLimit = 20;

/* Get all Tasks available (with limit set). */
ActivityManager mgr = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
List<ActivityManager.RunningTaskInfo> allTasks = mgr.getRunningTasks(showLimit);
/* Loop through all tasks returned. */
for (ActivityManager.RunningTaskInfo aTask : allTasks) 
{                  
    Log.i("MyApp", "Task: " + aTask.baseActivity.getClassName()); 
    if (aTask.baseActivity.getClassName().equals("com.android.email.activity.MessageList")) 
        running=true;
}

Answer 6

I combined two solutions in one method and it works for me for API 24 and for API 21. Others I didn't test.

The code in Kotlin:

private fun isAppInForeground(context: Context): Boolean {
    val appProcessInfo = ActivityManager.RunningAppProcessInfo()
    ActivityManager.getMyMemoryState(appProcessInfo)
    if (appProcessInfo.importance == IMPORTANCE_FOREGROUND ||
            appProcessInfo.importance == IMPORTANCE_VISIBLE) {
        return true
    } else if (appProcessInfo.importance == IMPORTANCE_TOP_SLEEPING ||
            appProcessInfo.importance == IMPORTANCE_BACKGROUND) {
        return false
    }

    val am = context.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
    val foregroundTaskInfo = am.getRunningTasks(1)[0]
    val foregroundTaskPackageName = foregroundTaskInfo.topActivity.packageName
    return foregroundTaskPackageName.toLowerCase() == context.packageName.toLowerCase()
}

and in Manifest

<!-- Check whether app in background or foreground -->
<uses-permission android:name="android.permission.GET_TASKS" />