android intercept recent apps button

Question

I have an application meant for children and I do not want them to be able to click the "Recent Apps" button (the one that looks like two rectangles on top of each other). I am taking care of capturing the back button and the home button and I have searched and read a lot about about trying to capture the Recent Apps button, but most say you cannot or the way they do it is very questionable.

The App "Kids Place" pops up a view that says "Action Not Allowed" and redirects you to its home screen if you press the Recent Apps button, this works even if you are in a different app, so how are they doing this?

Any suggestions, hints would be appreciated.

Thanks.

Answer 1

After lots of searching and coding the current best solution I found is the following:

   @Override
public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);

    if (!hasFocus) {
        windowCloseHandler.postDelayed(windowCloserRunnable, 0);
    }
}

private void toggleRecents() {
    Intent closeRecents = new Intent("com.android.systemui.recent.action.TOGGLE_RECENTS");
    closeRecents.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
    ComponentName recents = new ComponentName("com.android.systemui", "com.android.systemui.recent.RecentsActivity");
    closeRecents.setComponent(recents);
    this.startActivity(closeRecents);
}

private Handler windowCloseHandler = new Handler();
private Runnable windowCloserRunnable = new Runnable() {
    @Override
    public void run() {
        ActivityManager am = (ActivityManager)getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
        ComponentName cn = am.getRunningTasks(1).get(0).topActivity;

        if (cn != null && cn.getClassName().equals("com.android.systemui.recent.RecentsActivity")) {
            toggleRecents();
        }
    }
}

This requires that you use <uses-permission android:name="android.permission.GET_TASKS" />

When using this approach when the user presses the recent apps button it will cause your activity will go through the activity lifecycle as follows: onPause -> onWindowFocusChanged -> onResume.

To the user the behavior appears that pressing the recent apps button has no response. NOTE: that I have found that if you press the recent apps button quickly it will display that view for brief time.

This is not the best solution, but it is a stab at it. If you have a better solution please share.

Answer 2

The best way I have found is to do this:

public class BaseActivity extends Activity {
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);

            Log.d("Focus debug", "Focus changed !");

        if(!hasFocus) {
            Log.d("Focus debug", "Lost focus !");

            Intent closeDialog = new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
            sendBroadcast(closeDialog);
        }
    }
}// all credit goes here: http://www.juliencavandoli.com/how-to-disable-recent-apps-dialog-on-long-press-home-button/

This is not my own code, but this just hides the recent apps list from showing.