private void drawPath(){
    Paint p = new Paint();
    p.setStrokeWidth(5);
    p.setColor(Color.RED);
    p.setStyle(Paint.Style.STROKE);

    Canvas canvas = new Canvas(bitmap);

    Path path =new Path();
    path.moveTo(200, 200);
    path.lineTo(400, 200);
    path.lineTo(400, 400);
    path.close();
    canvas.drawPath(path, p);
}