Animation not working on UIImageView

Question

I have a UIImageView added as a subview. I am trying to animate it using transform. The animation doesn't, however the imageview is Scaled properly, it's just not auto reversing. Am I doing something wrong?

UIImageView * iv_tap = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"gesture_tap"]];
    iv_tap.center = point;
    iv_tap.tag = 779;
    iv_tap.hidden = true;
    [UIView animateWithDuration:2.0
                          delay:.05
                        options: UIViewAnimationOptionAutoreverse | UIViewAnimationOptionRepeat | UIViewAnimationOptionCurveLinear
                     animations:^{
                         iv_tap.transform = CGAffineTransformScale(CGAffineTransformIdentity, 1.8, 1.8);
                     }
                     completion:NULL];


    [self addSubview:iv_tap];

Teja Nandamuri · Accepted Answer · 2015-12-18T20:49:07.107

1

You need to do the animation after you add the imageView into the view. If you do the animation before the addSubView where at point, the image view is not in the view heirarchy and you can't see any animation.

 UIImageView * iv_tap = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"gesture_tap"]];
[self.view addSubview:iv_tap];   //this could be self in your case
iv_tap.tag = 779; 

[UIView animateWithDuration:2.0 delay:0.05  options:UIViewAnimationOptionCurveEaseOut animations:^{

    iv_tap.center=self.view.center;
    iv_tap.transform = CGAffineTransformScale(CGAffineTransformIdentity, 1.8, 1.8);

    [self.view layoutIfNeeded];    //this could be self in your case

} completion:^(BOOL finished) {
        //do your stuff when animation is done
}];

If you are subclassing a UIView, then you can even put this in the drawRect method:

UIImageView * iv_tap = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"gesture_tap"]];
[self addSubview:iv_tap];   
iv_tap.tag = 779;

[UIView animateWithDuration:2.0 delay:0.05  options:UIViewAnimationOptionCurveEaseOut animations:^{

    iv_tap.center=self.center;
    iv_tap.transform = CGAffineTransformScale(CGAffineTransformIdentity, 1.8, 1.8);

    [self layoutIfNeeded];   

} completion:^(BOOL finished) {
        //do your stuff when animation is done
 }];

edited Dec 18 '15 at 20:49

answered Dec 18 '15 at 20:17

Teja Nandamuri

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Actually that didn't do anything. – user-44651 Dec 18 '15 at 20:18
call layoutifneeded after the animation – Teja Nandamuri Dec 18 '15 at 20:33
I called [iv_tap layOUtIfNeeded] and it did not work either. – user-44651 Dec 18 '15 at 20:34
updated the answer @Firemarble. This is working for me – Teja Nandamuri Dec 18 '15 at 20:34
no,not the imageview, u need to update the self.viewq layoutifneeded – Teja Nandamuri Dec 18 '15 at 20:35
you can change the animation options according to your need – Teja Nandamuri Dec 18 '15 at 20:35
My UIView was subclassed. Placing it in the DrawRect did work. But I use animations in other parts of the app and did not have to use the DrawRect method. Why do you think that would be? I have done no different initialization that I have with the other UIViews. – user-44651 Dec 20 '15 at 16:32

Animation not working on UIImageView

1 Answers1