Back pressed events with system alert window

Question

I need to dismiss system alert window on back pressed and home button event.I have tried with onKeyEvent but in vain. As we can\'t cap

Answer 1

use below method to handle back button pressed.

  public void onBackPressed()
  {
        super.onBackPressed();
  }

Answer 2

You need to overwrite the onBackPressed method.

@Override
public void onBackPressed() {

    super.onBackPressed(); // remove this if u want to handle this event
}

Answer 3

It's simple. Follow these steps:

1. Create a view like Relative Layout, Linear Layout or Frame Layout Dynamically. 2. Override the dispatchKeyEvent while creating the view.
2. Add your original view into this dynamically created view with addView() method.
3. Add the dynamically created view to your Window Manager or Alert Dialog whichever you want.

Answer 4

Since it's a service that hosting an overlay window, It's a bit tricky solution but it is possible.

You should handle these 2 cases separately (overriding home button press, and back button press).

---

1. Overriding home button press:

Create this HomeWatcher class which contains a BroadcastReceiver that will notify when home button was pressed. Register this receiver only when your window comes up.

Android: associate a method to home button of smartphone

Inside your service onCreate method use this:

HomeWatcher mHomeWatcher = new HomeWatcher(this);
mHomeWatcher.setOnHomePressedListener(new OnHomePressedListener() {
    @Override
    public void onHomePressed() {
        yourWindow.hide()  //means: windowManager.removeView(view);
    }
    @Override
    public void onHomeLongPressed() {
    }
});
mHomeWatcher.startWatch();

---

2. Overriding back button press:

The idea is creating an empty layout as a data member of your window class, and attach your view to it (even if its an inflated XML layout).

For example, this is gonna be your window class:

public class MyWindow
{
    private WindowManager windowManager;
    private WindowManager.LayoutParams params;
    private View view;

    // Add this empty layout:
    private MyLayout myLayout;

    public MyWindow()
    {
        windowManager = (WindowManager) context.getSystemService(context.WINDOW_SERVICE);
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.your_original_window_layout, null);

        // Add your original view to the new empty layout:
        myLayout = new MyLayout(this);
        myLayout.addView(view, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
    }

    // And show this layout instead of your original view:
    public void show()
    {
        windowManager.addView(myLayout, params);
    }

    public void hide()
    {
        windowManager.removeView(myLayout);
    }
}

And now create the MyLayout class to override the back button press:

public class MyLayout extends LinearLayout
{
    private MyWindow myWindow;

    public MyLayout(MyWindow myWindow)
    {
        super(myWindow.context);

        this.myWindow = myWindow;
    }


    @Override public boolean dispatchKeyEvent(KeyEvent event)
    {
        if (event.getKeyCode() == KeyEvent.KEYCODE_BACK)
        {
            if (event.getAction() == KeyEvent.ACTION_DOWN  &&  event.getRepeatCount() == 0)
            {
                getKeyDispatcherState().startTracking(event, this);
                return true;

            }

            else if (event.getAction() == KeyEvent.ACTION_UP)
            {
                getKeyDispatcherState().handleUpEvent(event);

                if (event.isTracking() && !event.isCanceled())
                {
                    // dismiss your window:
                    myWindow.hide();

                    return true;
                }
            }
        }

        return super.dispatchKeyEvent(event);
    }
}

I know it's a bit complicated as I said since it's a system alert window hosted by a service, BUT it's working. I have the same issue as well and it has been solved exactly like that. Good luck.