UIView Animation not working to resize view

问题

I am using following code to animate the appearance of selectionMoreOptionView

[selectionMoreOptionView setFrame:CGRectMake(974, 56, 50, 0)];
[self.view insertSubview:selectionMoreOptionView aboveSubview:lightBoxView];
[lightBoxView setAlpha:0.0];

[UIView animateWithDuration:5.0
                      delay:0.0
                    options:UIViewAnimationOptionCurveLinear
                 animations:^{

                     [lightBoxView setAlpha:0.5];
                     [selectionMoreOptionView setFrame:CGRectMake(974, 56, 50, 100)];

                 } completion:^(BOOL finished) {
                 }];

But it is not animating instead it just appears at once without animating. What i am doing wrong?

回答1:

Simply try this

[UIView animateWithDuration:.5 animations:^(void){

   [lightBoxView setAlpha:0.5];
   [selectionMoreOptionView setFrame:CGRectMake(974, 56, 50, 100)];

}];

回答2:

The animation was working fine the problem was that i had two buttons inside the view big enough to cover all of the view. The views property Clip Subviews was unchecked. I had thought when a parent resizes it effects its child's automatically, but it don't in some cases when parent do not clip its subviews. Thanks everybody for your reply :)

回答3:

check your

[selectionMoreOptionView setFrame:CGRectMake(974, 56, 50, 100)];

I think XY co-ordinates going out of viewController. Try to bring it in the ViewController area,as of X should be possibly less than 320 and y<480 so that you can see your view.

来源：https://stackoverflow.com/questions/18184412/uiview-animation-not-working-to-resize-view