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moving view well by UIPanGestureRecognizer but sometimes goes jumpy



i am moving views by this code, it is moving well but sometimes they are very jumpy, any idea about this ?







[[[(UITapGestureRecognizer*)sender view] layer] removeAllAnimations];



[self.view bringSubviewToFront:[(UIPanGestureRecognizer*)sender view]];

CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];



if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {



firstX = [[sender view] center].x;

firstY = [[sender view] center].y;

}



translatedPoint = CGPointMake(firstX+translatedPoint.x, firstY+translatedPoint.y);



[[sender view] setCenter:translatedPoint];



if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {



CGFloat finalX = translatedPoint.x + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].x);

CGFloat finalY = translatedPoint.y + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].y);





[UIView beginAnimations:nil context:NULL];

[UIView setAnimationDuration:.35];

[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];

[[sender view] setCenter:CGPointMake(finalX, finalY)];

[UIView commitAnimations];




Comments

  1. It doesnt seem like anything in your code above would slow down panning. Any slow response on the UI is 99% of the time caused by re-drawing. Take a look at you drawRect code (if you have implemented it) for the views you are panning. If this is getting called everytime you pan, that may be causing you issues. You can resolve this by setting the rasterize property to YES in your view.

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