UIButton随中心更改大小

Question

I am animating the change in width and height of a UIButton in this way:

[UIView animateWithDuration:0.5
delay:0.0
                                    options: UIViewAnimationCurveEaseInOut
                                 animations:^{

                                     CGRect frame = [[sender view] frame];
                                     frame.size.width = 0;
                                     frame.size.height = 0;
                                     [[sender view] setFrame:frame];

                                 }
                                 completion:^(BOOL finished){

}];

The button is changing size just fine, but I would like it to close down on its centre, not on its corner. I know this is because it closes on the x and y coords, but can I make it close it down to the centre?

Answer 1

这是您在动画块中想要的：

[sender view].frame = (CGRect){[[sender view] center],CGSizeZero};

Answer 2

How about:

[UIView animateWithDuration:0.5
delay:0.0
                                options: UIViewAnimationCurveEaseInOut
                             animations:^{

                                 CGRect frame = [[sender view] frame];

                                 frame.origin.x += frame.size.width / 2.0f;
                                 frame.origin.y += frame.size.height / 2.0f;
                                 frame.size.width = 0;
                                 frame.size.height = 0;
                                 [[sender view] setFrame:frame];

                             }
                             completion:^(BOOL finished){

}];