OnTouch method in OnDraw

I need to set an onTouch method to the rect that I have set up but I dont know how to do this in an OnDraw method. this but I dont know how here my code, Thanks for the help!

public class Tab3 extends View implements OnTouchListener
 {
     int x1, x2, y1, y2;
     Rect Rect = new Rect();
     public Tab3(Context context, AttributeSet attrs)
     {
         super (context, attrs);
         x1 = 0;
         x2 = 100;
         y1 = 0;
         y2 = 100;
 
     }
 
     @Override
     protected void onDraw(Canvas canvas) 
     {
         // TODO Auto-generated method stub
         super.onDraw(canvas);
 
 
         Rect.set(x1, y1, x2, y2);
 
         Paint blue = new Paint();
         blue.setColor(Color.BLUE);
         canvas.drawRect(Rect, blue);
     }
 
     @Override
     public boolean onTouch(View v, MotionEvent event) 
     {
 
         return false;
     }
 }
 

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