how to draw a path on canvas after a specific time delay?

Question

I want to draw a path on canvas after a specific time delay, i have checked this link Draw a Path as animation on canvas but it does not explain the problem i am looking for.

i just want a delay before i draw a path.

private void OnPainSurface(object sender, SKPaintSurfaceEventArgs args)
 {
      canvas = args.Surface.Canvas;
      canvas.Clear();


      foreach (SKPath path in inProgressPaths.Values)
      {
           //Delay before drawing a path, ex: 5 seconds
           canvas.DrawPath(path, paint);
      }

}

Amine · Answer 1 · 2019-04-29T10:17:31.720

0

You can use postInvalidateDelayed method on a View

In your example that would be

foreach (SKPath path in inProgressPaths.Values)
  {
       //Delay before drawing a path, ex: 5 seconds
       TimeUnit.SECONDS.sleep(5);
       canvas.DrawPath(path, paint);
  }

EDIT

You can just use Handler to give a delay in each iteration, in Kotlin it's done like this

Handler().postDelayed({
    canvas.DrawPath(path, paint);
}, 5000)

EDIT 2

You can try this

Handler handler = new Handler();
Action action = () => 
{
   canvas.DrawPath(path, paint);
};

handler.postDelayed(action, 5000);

edited Apr 29 '19 at 10:17

answered Apr 23 '19 at 16:23

Amine

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this did not work, it is drawing everything instantly. – VINNUSAURUS Apr 23 '19 at 16:32
I edited the answer, can you try the new solution ? – Amine Apr 23 '19 at 16:36
yes i did that, i am calling `invalidate` on button press and inside the above `OnPaintSurface` method `foreach` loop i am calling this `canvasView.PostInvalidateDelayed(2000); canvas.DrawPath(path.Item2, paint);` – VINNUSAURUS Apr 23 '19 at 16:37
tried it crashed the app `Handler h = new Handler(); Action myAction = () => { canvas.DrawPath(path.Item2, paint); }; h.PostDelayed(myAction, 1000);` – VINNUSAURUS Apr 23 '19 at 16:45
What the crash says ? – Amine Apr 24 '19 at 09:32
i will check again tomorrow and revert :) – VINNUSAURUS Apr 24 '19 at 18:39
@LeonLu-MSFT Still waiting for the crash log – Amine Apr 29 '19 at 10:13

how to draw a path on canvas after a specific time delay?

1 Answers1