ios - 在 Objective C 中切换 View

Question

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    //  UIScreen represents the entire screen. Its bounds method
    //  returns the rectangle that corresponds to the entire screen
    //  CGRect is a C struct that used to group four floating
    //  point values that represent the x and y coordinates of the upper left
    //  corner, as well as the width and the height.
    //

    CGRect windowRect = [[UIScreen mainScreen] nativeBounds];
    UIWindow *window = [[UIWindow alloc] initWithFrame:windowRect];
    [window setBackgroundColor:[UIColor lightGrayColor]];

   [self setWindow:window];
    UIViewController *vc = [[UIViewController alloc]init];
    window.rootViewController = vc;

    self.mainView = vc.view;
    [window makeKeyAndVisible];

    //Window is now visible
    //Add created views to the mainView to make them visible.

    //Example : add a "Hello World" label
    UIView *dealerView=[[UIView alloc]initWithFrame:self.mainView.bounds];

    UIView *view1=[[UIView alloc]initWithFrame:self.mainView.bounds];
    CGRect labelRect = { 150.0, 150.0, 150.0, 50.0 };
    UIButton *button1 = [[UIButton alloc] initWithFrame:labelRect];
    [button1 setBackgroundColor:[UIColor blackColor]];
    [button1 setTitle:@"ENTER HERE" forState: (UIControlState)UIControlStateNormal];
    [button1 addTarget:self action:@selector(enterHereClicked:)
      forControlEvents:UIControlEventTouchUpInside];
    [button1 setUserInteractionEnabled:YES];

    [view1 addSubview:button1];

    [dealerView addSubview:view1];

    return YES;
}

-(void) enterHereClicked:(UIButton *) button{

   CGRect labelRect = { 150.0, 400.0, 150.0, 50.0 };

    UIButton *sender=button;
    UIView *view1=[sender superview];
    UIView *view2=[[sender superview]superview];
   [view1 removeFromSuperview];

    UIView *view=[[UIView alloc]initWithFrame:self.mainView.bounds];

    UIButton *button2 = [[UIButton alloc] initWithFrame:labelRect];
    [button2 setBackgroundColor:[UIColor blackColor]];
    [button2 setTitle:@"Another View" forState: (UIControlState)UIControlStateNormal];
    [button2 addTarget:self action:@selector(clickView:) forControlEvents:
     UIControlEventTouchUpInside];

    [view addSubview:button2];
    [view2 addSubview: view];

}
-(void)clickView:(UIButton *) button{

    NSLog(@"anand");
    UIButton *sender=button;
    UIView *view1=[sender superview];
      UIView *view3=[[sender superview]superview];
    [view1 removeFromSuperview];
     CGRect labelRect = { 150.0, 400.0, 150.0, 50.0 };
    UIView *view=[[UIView alloc]initWithFrame:labelRect];
    [view setBackgroundColor:[UIColor greenColor]];

    [view3 addSubview:view];



}



I have edited the code as per you advise. But still not working.

我正在创建一个新 View dealerview 并从中添加和删除 subview 。我要去哪里错了，但仍然无法弄清楚。 看起来我在 -(BOOL) 应用程序方法中出错了。

Answer 1

在应用委托(delegate)中做这种事情是非常不典型的。最好在 UIViewController 的子类中执行此操作，并将该子类的实例添加为 rootViewController 的 UINavigationController 您在 didFinishLaunchingWithOptions 中设置为 key 和可见。

您也可能不想从 UIViewController 的 super View 中删除 Root View 。目前，您关心的是为按钮创建一个操作，从 View 层次结构中删除其父 View vc.view 。问题是 view1 和 self.mainView 是一样的:

UIView *view1=[sender superview];
[view1 removeFromSuperview];
[self.mainView addSubview:view];

您正在从 View 层次结构中删除一个 View ，然后将一个 View 添加到刚刚删除的 View 中并希望看到它。

您应该有一个 View 充当 button1 的容器，另一个 View 充当 button2 的容器，但都添加到 self.mainView 或从 ojit_code 中删除。