模拟 UINavigation 推送问题？

Question

我想在一个 XIB 中切换两个视图，但我不想为此使用 UINavigationController，因为它的效率非常低，因为只需要发生一个转换。这是我的代码：

// get the view that's currently showing
UIView *currentView = self.view;
// get the the underlying UIWindow, or the view containing the current view view
UIView *theWindow = [currentView superview];

// set up an animation for the transition between the views
CATransition *animation = [CATransition animation];
[animation setDuration:0.5];
[animation setType:kCATransitionPush];
[animation setSubtype:kCATransitionFromLeft];
[animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]];

[theWindow addSubview:webViewTwo];

[[theWindow layer] addAnimation:animation forKey:@"SwitchToView1"];

.h

@class WebViewTwo;
@interface SecondViewController : UIViewController {
IBOutlet WebViewTwo *webViewTwo;
}

现在它因错误而崩溃

2011-05-12 16:59:59.528 TableView[36627:207] -[WebViewTwo superview]: unrecognized selector sent to instance 0x603b660
2011-05-12 16:59:59.531 TableView[36627:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[WebViewTwo superview]: unrecognized selector sent to instance 0x603b660'

请帮忙！谢谢。

Answer 1

该错误往往表明WebViewTwo 不是UIView 的子类，或者之前已被释放并且不再指向UIView 子类的对象。检查定义WebViewTwo 的头文件，并可能在将其添加为子视图之前添加NSLog(@"%@", webViewTwo);，以查看它是什么类型。

希望这会有所帮助。