I want to flash an UIImageview on the iPad, how do I do that?

Question

I want to let a UIImageView flash several times.

Currently I don\'t know how to do that.

Actual code:

-(void)arrowsAnimate{
    [UIVi         


        

Answer 1

Use

+ (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion

and pass the UIViewAnimationOptionRepeat and probably UIViewAnimationOptionAutoreverse in your options. You shouldn't need to provide a completion block and only perform the first animation.

Edit: here is some sample code for an image that fades in and out indefinitely.

[UIView animateWithDuration:1.0 
                      delay:0.0 
                    options:(UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse) 
                 animations:^{
                     self.myImageView.alpha = 1.0;
                 }
                 completion:NULL];

Edit 2: I see you actually need to flash it 10 times only. I wasn't able to do that with blocks actually. When the completion block executed, the animation seemed to complete instantly the remaining 9 times. I was however able to do this with just the old-style animations quite easily.

[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:1.0];
[UIView setAnimationRepeatCount:10.0];
[UIView setAnimationRepeatAutoreverses:YES];

self.myImageView.alpha = 1.0;

[UIView commitAnimations];

Edit 3: I found a way to do this with blocks.

- (void)animate
{
    if (self.animationCount < 10)
    {
        [UIView animateWithDuration:1.0 
                         animations:^{
                             self.myImageView.alpha = 1.0;
                         }
                         completion:^(BOOL finished){
                             [self animateBack];
                         }];
    }
}

- (void)animateBack
{
    [UIView animateWithDuration:1.0 
                     animations:^{
                         self.myImageView.alpha = 0.0;
                     }
                     completion:^(BOOL finished){
                         self.animationCount++;
                         [self animate];
                     }];
}