CODEWITHSUNDEEP
iosconcurrencyuiimageview
Manifestor
Manifestor

Reputation: 615

UIImageView draw with delay

I got a problem with drawing on UIImageView with delay. I got method [className drawPoint:(CGPoint)point] (this method can draw point and it works fine )

Next I want to draw 3 points from array in circle with a 1 sec delay, and if I use [self performSelector:withObject:afterDelay:] I will see all 3 points on UIImageView after 3 seconds delay. But I want it to draw point1 then after 1 second point2 and then after 1 second point3.

I've also tried to play with dispatch_async but didn't get desired result

Upvotes: 0

Views: 184

Answers (2)

xexe
xexe

Reputation: 346

Try to use:

 [self performSelectorInBackground:@selector(drawThreePoints) withObject:nil];

The drawThreePoints method:

-(void)drawThreePoints{
    [NSThread sleepForTimeInterval:1];
    [self performSelectorOnMainThread:@selector(drawPoint:) withObject:POINT1 waitUntilDone:NO];
    [NSThread sleepForTimeInterval:1];
    [self performSelectorOnMainThread:@selector(drawPoint:) withObject:POINT2 waitUntilDone:NO];
    [NSThread sleepForTimeInterval:1];
    [self performSelectorOnMainThread:@selector(drawPoint:) withObject:POINT3 waitUntilDone:NO];
}

The drawPoint: method:

-(void)drawPoint:(CGPoint)point{
     [className drawPoint:point];
}

UPD: Or, if points are from array, you can do it in the loop, of course :)

Upvotes: 1

Dylan Kirkby
Dylan Kirkby

Reputation: 1427

If you want to stagger the drawing of a view, drawRect is not the place to do it. A better solution would be to draw everything you want to draw in drawRect (or separate out your staggered elements into different views each with their own drawRect) and to toggle the hidden property with UIView's class method animateWithDuration.

Upvotes: 2

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