在片段中使用onTouch绘图

Question

我有问题。我想在片段中画圆圈。当我触摸一个圆圈时，我想重新启动。所以所有被触摸的圈子都应该成为一种新的颜色。 问题是onDraw只启动一次。我试图使布局无效，但它没有帮助。 有谁知道如何解决这个问题？

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}



@SuppressLint("ClickableViewAccessibility")
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable final ViewGroup container, Bundle savedInstanceState) {
    final View fraglayoutv3 = inflater.inflate(R.layout.frag3_layout,null);

    final LinearLayout touchLayout = (LinearLayout) fraglayoutv3.findViewById(R.id.touchLayout);
    touchLayout.addView(new Leds(getActivity()));


    coordinates = "Coordinates: ";
    touchLayout.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if(event.getAction()==MotionEvent.ACTION_DOWN){
                int x=(int)event.getX();
                int y=(int)event.getY();
                int xy = 0;
                int d = 24;
                xPos=0;
                yPos=0;

                Log.v("TAG", x+" | "+y);
                for(int i=0;i<32;i++)
                {
                    if(x>xy && x<xy+d){
                        xPos = i;
                    }
                    xy+=d;
                }
                xy=0;
                for(int i=0;i<80;i++){
                    if(y>xy && y<xy+d){
                        yPos = i;
                    }
                    xy+=d;
                }
                coordinates += (xPos + ";" +yPos +";");
                xArray[nr] = x;
                yArray[nr] = y;
                nr++;
                data = true;
            }
            Log.v("Tag",coordinates);
            return true;
        }
    });
    return fraglayoutv3;
}

@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
}


private class Leds extends View{
    Paint paint = new Paint();
    Paint paintText = new Paint();
    Paint paintLeds = new Paint();

    public  Leds(Context context){
        super(context);
    }
    @Override
    public void onDraw(Canvas canvas){
        paint.setColor(Color.BLACK);
        paintText.setColor(Color.GREEN);
        paintLeds.setColor(Color.YELLOW);
        //int a=20;   // Offset x-Achse
        //int b=50;   // Offset y-Achse
        int a =12;
        int b=12;
        int nummer = 0;
        for(int j=0;j<80;j++){  // 80 Zeilen lang
            for(int i=0;i<32;i++){  // 32 Spalten
                canvas.drawCircle(a,b,12,paint);
                canvas.drawText(i+"|"+j,a-10,b,paintText);
                nummer++;
                a+=24;
            }
            //a = 20;
            b+=24;
            a=12;
        }
        Log.v("TAG", "Touch");
        for(int i=0;i<nr;i++){
            canvas.drawCircle(xArray[i],yArray[i],12,paintLeds);
        }
    }
}
}