使用动画以编程方式更改 tabbarController 的选项卡

Question

我想通过带有动画的代码更改选项卡。确切的情况是有 2 个选项卡具有以下层次结构。

First tab
  - Navigation controller
    - Login controller
    - Some other controller
Second tab
  - Navigation controller
    - Screen with Logout button

现在，如果用户按下注销，我需要显示登录屏幕。为此，我需要将选项卡切换到 FirstTab，然后 popToRootViewController。

所以我正在做的是按下注销按钮我将NSNotification 发送到LoginController，然后执行下面的方法。

- (void)logoutButtonPressed
{
    // Go to root controller in navigation controller of first tab.
    [self.navigationController popToRootViewControllerAnimated:YES];

    // Change tab to "First tab". This happens sharply without animation.
    // I want to animate this change.
    self.tabBarController.selectedIndex = 0;
}

我尝试了以下方法来制作动画。但这仅在用户更改选项卡而不是通过代码更改时才会显示动画。

- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
{
    NSArray *tabViewControllers = tabBarController.viewControllers;
    UIView * fromView = tabBarController.selectedViewController.view;
    UIView * toView = viewController.view;
    if (fromView == toView)
        return false;
    NSUInteger fromIndex = [tabViewControllers indexOfObject:tabBarController.selectedViewController];
    NSUInteger toIndex = [tabViewControllers indexOfObject:viewController];

    [UIView transitionFromView:fromView
                        toView:toView
                      duration:0.3
                       options: toIndex > fromIndex ? UIViewAnimationOptionTransitionFlipFromLeft : UIViewAnimationOptionTransitionFlipFromRight
                    completion:^(BOOL finished) {
                        if (finished) {
                            tabBarController.selectedIndex = toIndex;
                        }
                    }];

    return true;
}

Answer 1

下面是我用来为具有滑入滑出效果的屏幕制作动画的代码。发现于SO question。

- (void)logoutButtonPressed
{
    [self.navigationController popToRootViewControllerAnimated:NO];

    [self animateTransitionBetweenControllers];
}

// Animates view transition that happens from screen with logout button to login screen
- (void)animateTransitionBetweenControllers
{
    // Get the views to animate.
    UIView * fromView = self.tabBarController.selectedViewController.view;
    UIView * toView = [[self.tabBarController.viewControllers objectAtIndex:0] view];

    // Get the size of the view.
    CGRect viewSize = fromView.frame;

    // Add the view that we want to display to superview of currently visible view.
    [fromView.superview addSubview:toView];

    // Position it off screen. We will animate it left to right slide.
    toView.frame = CGRectMake(-self.view.bounds.size.width, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);

    // Animate transition
    [UIView animateWithDuration:0.3 delay:0.0 options:UIViewAnimationOptionTransitionNone animations:^{
        // Animate the views with slide.
        fromView.frame = CGRectMake(self.view.bounds.size.width, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);
        toView.frame = CGRectMake(0, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);
    } completion:^(BOOL finished) {
        if (finished)
        {
            // Remove the old view.
            [fromView removeFromSuperview];
            self.tabBarController.selectedIndex = 0;
        }
    }];
}

Answer 2

试试这个

- (void)logoutButtonPressed
{
    // Go to root controller in navigation controller of first tab.
    [self.navigationController popToRootViewControllerAnimated:YES];


    NSArray *tabViewControllers = self.tabBarController.viewControllers;


    UIView * fromView = self.tabBarController.selectedViewController.view;


    UIView * toView = self.view;

    NSUInteger fromIndex = [tabViewControllers indexOfObject:self.tabBarController.selectedViewController];


    NSUInteger toIndex = [tabViewControllers indexOfObject:self];

    [UIView transitionFromView:fromView
                        toView:toView
                      duration:0.3
                       options: toIndex > fromIndex ? UIViewAnimationOptionTransitionFlipFromLeft : UIViewAnimationOptionTransitionFlipFromRight
                    completion:^(BOOL finished) {

                            self.tabBarController.selectedIndex = 0;

                    }];


}

Answer 3

对不起 Geek，我周末断线了。

我在我的应用程序中采用的解决方案是创建一个调用popToRootViewControllerAnimated: 的方法，然后将performSelector: 消息发送到self，将创建的方法作为选择器传递：

- (void)delayPopAnimation {
    [self.navigationController popToRootViewControllerAnimated:YES];
}

// in logoutButtonPressed make some like this
self.tabBarController.selectedIndex = 0;
[self performSelector:@selector(delayPopAnimation) withObject:nil afterDelay:1.5];

也许它不是最好的和执行良好的解决方案，但它是一种选择，因为做这项工作。它将选择选项卡，并在 1.5 秒延迟后播放动画。希望对您有所帮助。