objective-c - 如何在过渡时不停止动画的情况下过渡到 modalViewController

Question

我注意到，如果我在 Controller “A”的某个元素上启动 UIView 动画并呈现带有过渡的 Controller B，则之前提交的动画不会启动。
例如:

//apply a UIView animation before transitioning
[UIView animateWithDuration: 1 delay:0 options:UIViewAnimationOptionCurveEaseOut             animations:^{
        someUIView.frame = newFrame;
 }completion:nil];
//transition from  controller A to controller B
controllerB.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController: controllerB animated:YES];

如果动画已经开始并且我尝试转换到 Controller B，则 A 中的动画将停止。我注意到这种行为取决于使用的转换类型。例如，如果使用“UIModalTransitionStyleCoverVertical”，则不会出现问题。
有什么想法吗？

Answer 1

只需从动画完成 block 中展示您的 Controller B

[UIView animateWithDuration: 1 
                      delay:0
                    options:UIViewAnimationOptionCurveEaseOut
                 animations:^{
                     someUIView.frame = newFrame;
                }completion:^{
                   //transition from  controller A to controller B
                   controllerB.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
                   [self presentModalViewController: controllerB animated:YES];
 }];