android - SlidingDrawer to only take up the space it needs?

Question

I am trying to make a System Overlay in android such that another view will be able to slide in from the side.

However, the problem is that the SlidingDrawer always fills the screen up for it to work. If, for example, I set it to wrap_content, it wouldn't work because the sliding drawer does not actually show until the button starts sliding, but since the button already filled up the whole of the view, there is no space for it to slide to.

Here are some pictures (the white part is the RelativeLayout, black is the handle, and blue is the drawer):

WRAP_CONTENT: https://i.stack.imgur.com/AV5fW.png

MATCH_PARENT: https://i.stack.imgur.com/KH8sf.png

I tried to set a OnTouchListener, so that when the user touches the handle, the SlidingDrawer will be set to MATCH_PARENT, but it does not work:

handle.setOnTouchListener(new View.OnTouchListener() {
        public boolean onTouch(View v, MotionEvent event) {
            if (event.getAction() == MotionEvent.ACTION_DOWN) {



            slidingdrawer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
            return true;
            }
            return false;
        }
});

This is another part of the code:

@Override
public boolean onTouchEvent(MotionEvent event) {

     if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {

        onTouchEvent_Press(event);

    } else if (event.getActionMasked() == MotionEvent.ACTION_UP) {

        onTouchEvent_Up(event);

    } else if (event.getActionMasked() == MotionEvent.ACTION_MOVE) {

        onTouchEvent_Move(event);

    }

    return super.onTouchEvent(event);

}


@Override
protected void onTouchEvent_Up(MotionEvent event) {
    if (!slidingdrawer.isOpened())
    {
        slidingdrawer.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

    }

    else{

        slidingdrawer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
    }
}

@Override
protected void onTouchEvent_Press(MotionEvent event) {
    slidingdrawer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
}

Can anyone help? It seems so easy, but I just can't get it to work.