Question

我在UIViewController的导航栏中以编程方式创建了一个UISegmentedControl，我希望能够在切换分段控件时切换视图控制器。

这是我到目前为止所做的：

 @interface TVExploreViewController : TVViewController

    @property (nonatomic, strong) UISegmentedControl *scopeControl;
    @property (nonatomic, assign) NSInteger scope;
    @property (nonatomic, strong) UIViewController *premiumContentViewController;
    @property (nonatomic, strong) UIViewController *trendingContentViewController;
    @property (nonatomic, strong) UIViewController *currentViewController;

 @end

TVExploreViewController的实现：

- (void)viewDidLoad {
      [super viewDidLoad];
      _scopeControl = [[UISegmentedControl alloc] initWithItems:[NSArray arrayWithObjects:@"TV & MOVIES", @"VIRAL CLIPS", nil]];
      [_scopeControl setFrame:CGRectMake(80, 0, 200, 30)];
      [_scopeControl addTarget:self
                     action:@selector(scopeChanged:)
                     forControlEvents:UIControlEventValueChanged];
      [[self navigationItem] setTitleView:_scopeControl];
      [_scopeControl setSelectedSegmentIndex:0];

      _premiumContentViewController = [[TVPremiumContentViewController alloc] init];
      _trendingContentViewController = [[TVTrendingFeedController alloc] init];
      [self setScope:0];
}

- (void)scopeChanged:(id)sender {
    [self setScope:self.scopeControl.selectedSegmentIndex];
}

- (void)transitionToViewController:(UIViewController *)controller
{
    [self.currentViewController willMoveToParentViewController:nil];
    if (controller) {
        [self addChildViewController:controller];
    }

    controller.view.frame = self.view.bounds;
    [self.view addSubview:controller.view];
    [self.currentViewController.view removeFromSuperview];
    [self.currentViewController removeFromParentViewController];
    [controller didMoveToParentViewController:self];
    self.currentViewController = controller;
}

- (void)setScope:(NSInteger)scope {
    if (scope != _scope) {
        _scope = scope;
        UIViewController *nextController = nil;

        if (_scope == 0) {
            nextController = self.premiumContentViewController;
        } else if (_scope == 1) {
            nextController = self.trendingContentViewController;
        }
        [self transitionToViewController:nextController];
    }
}

当我在TVExploreViewController中切换分段控件时，视图的其余部分保持白色并且没有加载视图控制器。谁知道我做错了什么？

Answer 1

这不是答案，但在这里写一些日志代码很方便。

你能告诉我方法中的日志吗？

- (void)transitionToViewController:(UIViewController *)controller
{
    [self.currentViewController willMoveToParentViewController:nil];
    if (controller) {
        [self addChildViewController:controller];
    }

    controller.view.frame = self.view.bounds;
    [self.view addSubview:controller.view];
    [self.currentViewController.view removeFromSuperview];
    [self.currentViewController removeFromParentViewController];
    [controller didMoveToParentViewController:self];
    self.currentViewController = controller;

    // can you show me the log here ?
    NSLog(@"%@, %@, %@", controller.view, controller.view.superview, self.view) ;
    // you should see the subviews that you added.
    NSLog(@"subviews:%@", [controller.view subviews]) ;
}

Answer 2

将Viewcontrollers添加到ViewController真的不是一个好主意，你应该总是在屏幕上有一个ViewController。您可以使用NavigationController执行此操作，而无需动画。

无法使用分段控制在2个视图控制器之间切换

2 个答案: