讓一個視圖控制器消失

Question

我正在嘗試一個多視圖應用程序，但我似乎無法得到第一個視圖控制器消失，當我把新的視圖控制器。我在索引0處放置第二個（即將到來的）視圖控制器，並將它放置在背景中。我認爲[going.view removeFromSuperview]將刪除原視圖 - 控制，但是這不是發生了什麼......

UIViewController *coming = nil; 
    UIViewController *going = nil; 
    UIViewAnimationTransition transition; 

    if (answer == YES) 
    { 
     coming = boyController; 
     going = getInfoController; 
     transition = UIViewAnimationTransitionFlipFromLeft; 
    } 
    else 
    { 
     coming = girlController; 
     going = getInfoController; 
     transition = UIViewAnimationTransitionFlipFromLeft; 
    } 
    NSLog(child); 
    [UIView setAnimationTransition:transition forView: self.view cache:YES]; 
    [coming viewWillAppear:YES]; 
    [going viewWillDisappear:YES]; 
    [going.view removeFromSuperview]; 
    [self.view insertSubview:coming.view atIndex:0]; 
    [going viewDidDisappear:YES]; 
    [coming viewDidAppear:YES]; 

    [UIView commitAnimations]; 

Answer 1

首先一點重構：

coming = (answer ? boyController : girlController); 

可以刪除going和transition，因爲它們只用過一次。然後，要實際執行動畫，您需要將所有內容放入動畫塊的上下文中。

[UIView beginAnimations:@"flipAnimation" context:NULL]; 
[UIView setAnimationTransition:transition forView:self.view cache:YES]; 
[getInfoController.view removeFromSuperview]; 
[self.view addSubview:coming.view]; 
[UIView commitAnimations]; 

viewWillAppear:和viewWillDisappear:是委託方法。這些將在這些視圖的代表中自動調用，如果有的話。他們不應該被手動調用。