animation - iPhone - UINavigationController - 使用 CATransaction 自定义动画

Question

我正在尝试为 UINavigationController 创建一个类别，以便我可以将一些自定义动画放在一起。我遇到了this question这让我开始了。我提出了以下推送功能:

- (void)pushViewControllerMoveInFromBottom:(UIViewController *)viewController {
    [CATransaction begin];
    CATransition *transition;
    transition = [CATransition animation];
    transition.type = kCATransitionMoveIn;
    transition.subtype = kCATransitionFromBottom;
    transition.duration = 0.7;

    [CATransaction setValue:(id)kCFBooleanTrue
                     forKey:kCATransactionDisableActions];

    [[[[self.view subviews] objectAtIndex:0] layer] addAnimation:transition forKey:nil];
    [self  pushViewController:viewController animated:YES];
    [CATransaction commit];
}

我不明白通过 subview 调用访问哪个 View /层。因此，如果有人能帮助我理解这一点，那将会很有帮助。它似乎会影响即将出现在屏幕上的任何 View 。

但是我的主要问题是我正在尝试创建一个弹出窗口来“撤消”上述功能。为了清楚起见，假设我有两个 View ，A 和 B。A 是屏幕上显示的第一个 View 。上面的函数将移入 B 而不将 A 推出。很像模态视图。但下面的函数将 A 滑回 B 上方，而不是将 B 向上滑动并将 A 留在原处。

- (void)popViewControllerMoveInFromTop {
    [CATransaction begin];
    CATransition *transition;
    transition = [CATransition animation];
    transition.type = kCATransitionMoveIn;
    transition.subtype = kCATransitionFromTop;
    transition.duration = 0.7;

    [CATransaction setValue:(id)kCFBooleanTrue
                     forKey:kCATransactionDisableActions];

    [[[[self.view subviews] objectAtIndex:0] layer] addAnimation:transition forKey:nil];
    [self  popViewControllerAnimated:YES];    
    [CATransaction commit];
}

我不想使用模态视图，也不想使用自定义动画 block 来更改 View 的框架。

Answer 1

我已经完成了类似的事情，尽管我没有费心将它移到它自己的函数中:

CATransition *transition = [CATransition animation];
transition.duration = 0.5;
transition.type = kCATransitionMoveIn;
transition.subtype = kCATransitionFromBottom;
[self.navigationController.view.layer addAnimation:transition forKey:nil];

[self.navigationController popViewControllerAnimated:NO]

你可以把它抽象出来。使用您的代码，它看起来像:

- (void)popViewControllerMoveInFromTop {
[CATransaction begin];
CATransition *transition;
transition = [CATransition animation];
transition.type = kCATransitionMoveIn;
transition.subtype = kCATransitionFromTop;
transition.duration = 0.7;

[CATransaction setValue:(id)kCFBooleanTrue
                 forKey:kCATransactionDisableActions];

[self.view.layer addAnimation:transition forKey:nil];
[self  popViewControllerAnimated:NO];    
[CATransaction commit];
}

您还可以使用 UIView 的动画为弹出窗口创建自定义过渡。在这里，您将动画应用于即将消失的 View ，然后将其从 View 堆栈中弹出:

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.75];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.navigationController.view cache:NO]; 

[self.navigationController popViewControllerAnimated:NO];

[UIView commitAnimations];