交叉溶解根视图控制器变化的动画？答案

【问题标题】：Cross disolve the animation of RootViewController change?交叉溶解根视图控制器变化的动画？
【发布时间】：2012-09-23 21:44:20
【问题描述】：

如何更改 UIWindow 中的 RootViewController 并将其交叉溶解到新的根目录？

【问题讨论】：

标签： objective-c animation view controller root

【解决方案1】：

我建议在UIView 上使用transitionFromView 方法。例如，您可以使用以下代码来处理您的转换：

- (void)transitionToViewController:(UIViewController *)viewController
                    withTransition:(UIViewAnimationOptions)transition
{
    [UIView transitionFromView:self.window.rootViewController.view
                        toView:viewController.view
                      duration:0.65f
                       options: UIViewAnimationOptionTransitionCrossDissolve
                    completion:^(BOOL finished){
                        self.window.rootViewController = viewController;
                    }];
}

你可以找到这个方法的参考文档here。

【讨论】：

如果您想更好地控制何时设置根视图控制器，您还应该考虑使用transitionWithView:duration:options:animations:completion:，如本问题所述。

【解决方案2】：

让我们看看我的例子来了解如何切换rootviewcontroller。

 - (void)showTutorialsScreen:(BOOL)animated
{
   NUDTutorialsViewController *tutorialsVC = [[NUDTutorialsViewController alloc] initWithNibName:NSStringFromClass([NUDTutorialsViewController class]) bundle:nil];
   UINavigationController *tutorialsNavController = [[UINavigationController alloc] initWithRootViewController:tutorialsVC];

   [self switchRootViewController:tutorialsNavController animated:animated completion:nil];

}

- (void)showLoadingScreen:(BOOL)animated
{
   NUDLoadingViewController *loadingVC =  [[NUDLoadingViewController alloc]   initWithNibName:NSStringFromClass([NUDLoadingViewController class]) bundle:nil];

   [self switchRootViewController:loadingVC animated:animated completion:nil];

}

- (void)showMainScreen:(BOOL)animated
{
    NUDMainViewController *mainVC = [[NUDMainViewController alloc] initWithNibName:NSStringFromClass([NUDMainViewController class]) bundle:nil];
    UINavigationController *mainNavController = [[UINavigationController alloc] initWithRootViewController:mainVC];

    [self switchRootViewController:mainNavController animated:animated completion:nil];

}

 - (void)switchRootViewController:(UIViewController *)aRootViewController animated:(BOOL)animated completion:(void(^)())completion
 {
    if (animated) {
      [UIView transitionWithView:self.window duration:0.3 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
        BOOL oldState = [UIView areAnimationsEnabled];
        [UIView setAnimationsEnabled:NO];
        self.window.rootViewController = aRootViewController;
        [UIView setAnimationsEnabled:oldState];
    } completion:^(BOOL finished) {
        if (completion) completion();
    }];
 }
   else {
       self.window.rootViewController = aRootViewController;
        if (completion) completion();
   }
 }

【讨论】：