Question

i currently have a default looping animation which fade in and out once the view appear, when background processing of data are completed it will stop the current animation an load new animation, in terms of new picture.

i can’t seen to stop the animation using [self.view.layer removeAllAnimations]; [self.imageViewBottom.layer removeAllAnimations]; [self.imageViewTop.layer removeAllAnimations];

-(void)nextAnimation:(float)previousWidth {

//picture loop
imageViewTop.image = imageViewBottom.image;
imageViewBottom.image = [imageArray objectAtIndex:[imageArray count] - 1];

[imageArray insertObject:imageViewBottom.image atIndex:0];
[imageArray removeLastObject];
imageViewTop.alpha = 1.0;
imageViewBottom.alpha = 0.0;

[UIView animateWithDuration:4.0
                 animations:^{ 
                     imageViewTop.alpha = 0.0;
                     imageViewBottom.alpha = 1.0;
                     } 
                 completion:^(BOOL  completed){
                     [self nextAnimation:stringsize.width];
                 }
 ]; 



-(void)foundSetup
{   
    //[imageViewTop removeFromSuperview];
    //[imageViewBottom removeFromSuperview];
    //[buttonCaption removeFromSuperview];
    [self.view.layer removeAllAnimations];
    [self.imageViewBottom.layer removeAllAnimations];
    [self.imageViewTop.layer removeAllAnimations];


    //[self.imageArray removeAllObjects];
    //self.imageArray = foundImageArray;
} 

Answer 1

[UIView animateWithDuration:4.0                  
    animations:^{                       
   imageViewTop.alpha = 0.0;                      
    imageViewBottom.alpha = 1.0;                      
    }                   
    completion:^(BOOL  completed){                      
    [self nextAnimation:stringsize.width];                  
    } 

Here, in your completion block, you will call the next animation method again regardless of the animation being cancelled or not.

Inside your completion block, only call nextAnimation if completed == YES:

completion:^(BOOL  completed){                      
if (completed)        
    [self nextAnimation:stringsize.width];                  
    }

This, coupled with removing animations from the views that are actually being animated as suggested by Till, should do it for you.