Question

我在右侧设置了两个按钮项目，在左侧设置了一个按钮项目。正确的一个在两个视图之间成功地改变，而右边的第二个是一个分段控件，它应该在两个视图之间改变，就像明智一样。这是我的代码，我想知道如何使用分段控件实现更改视图。

- (void)setupNavigationBar {
    UINavigationBar *navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0,  self.view.frame.size.width, 44.0f)];
    UINavigationItem *navItem = [[UINavigationItem alloc] initWithTitle:@"ContainerView"];
    navItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFastForward target:self action:@selector(switchViewControllers)];
    navBar.items = [NSArray arrayWithObject:navItem];
    segmented = [[UISegmentedControl alloc] initWithItems:
                                  [NSArray arrayWithObjects:
                                   [UIImage imageNamed:@"seg1.png"],
                                   [UIImage imageNamed:@"seg1.png"],
                                   nil]];
    segmented.frame = CGRectMake(0, 0, 50, 30);

    segmented.segmentedControlStyle = UISegmentedControlStyleBar;

    UIBarButtonItem * segmentedBarItem = [[UIBarButtonItem alloc]  initWithCustomView:segmented];
    navItem.leftBarButtonItem = segmentedBarItem;

    [self.view addSubview:navBar];
}

- (void)viewDidLoad {
    [super viewDidLoad];

    // This is just for the purpose of calling the switch method.
    [self setupNavigationBar];

    CGRect rect = CGRectMake(0, 44, 320, 436);

    currentViewController = [[FirstViewController alloc] init];
    currentViewController.view.frame = rect;

    nextViewController = [[SecondViewController alloc] init];
    nextViewController.view.frame = rect;

    [self addChildViewController:currentViewController];
    [self addChildViewController:nextViewController];

    [self.view addSubview:currentViewController.view];
}

- (void)switchViewControllers {
    [self transitionFromViewController:currentViewController toViewController:nextViewController duration:3.0 options:UIViewAnimationTransitionFlipFromRight | UIViewAnimationOptionCurveEaseInOut animations:nil completion:^(BOOL finished) {
        UIViewController *tempViewController = currentViewController;
        currentViewController = nextViewController;
        nextViewController = tempViewController;
        tempViewController = nil;
    }];
}

如何实现分段控件来更改视图？

Answer 1

在UISegmentedControl

上添加UINavigationBar

编辑：

NSArray *itemArray = [NSArray arrayWithObjects:
                      [UIImage imageNamed:@"1.png"],
                      [UIImage imageNamed:@"2.png"],
                      nil];

UISegmentedControl* menuSegmentedButton = [[UISegmentedControl alloc] initWithItems:itemArray];
menuSegmentedButton.momentary = YES;
menuSegmentedButton.selected = NO;
menuSegmentedButton.segmentedControlStyle = UISegmentedControlStyleBar;
   [menuSegmentedButton addTarget:self action:@selector(doMenu)
              forControlEvents:UIControlEventValueChanged];
[menuSegmentedButton sizeToFit];
UIBarButtonItem* barButton = [[UIBarButtonItem alloc]
                              initWithCustomView:menuSegmentedButton];
self.navigationItem.leftBarButtonItem = barButton;

为分段按钮添加此方法

-(void)doMenu
{
    /// code for segment button tapped
}

Answer 2

我认为性能问题可能需要单独的视图控制器而不是两个子视图，但它要复杂得多 - 你会有一个非常复杂的导航系统，需要为每个视图设置段控制。我确信有另一种方法可以对视图进行子类化，但我对此不熟悉，因此建议使用一个包含视图的视图控制器。

注意：如果您要以编程方式在每个视图中创建所有对象，则可以通过从任何隐藏视图中删除对象来获得出色的性能。

首先你有一个UISegmentedControl（在iPatel的回答中创建）。但请添加此行[ctrl addTarget:self action:@selector(switchViewControllers) forControlEvents:UIControlEventValueChanged];

然后在switchViewControllers put：

if (ctrl.selectedSegmentIndex == 0) {
    NSLog(@"One");
    self.viewOne.hidden = NO;
    self.viewTwo.hidden = YES;

    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults setObject:@"showView" forKey:@"viewOne"];
    [defaults synchronize];
}
else if (ctrl.selectedSegmentIndex == 1) {
    NSLog(@"Two");
}

-(void)viewDidLoad {
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    if ([[defaults objectForKey:@"showView"] isEqualToString:@"viewOne"]) {
        self.viewOne.hidden = NO;
        self.viewTwo.hidden = YES;
    }
    else if (...) {

    }
}

切换段控件时，上述操作应该有效。在每个if中，您可以切换两个视图的可见性。您可以创建不同的视图作为主视图的子视图;一个在另一个之上。您需要在Interface Builder或viewDidLoad中隐藏一个视图（我建议将当前视图存储在NSUserDefaults中并在用户首次加载视图控制器时显示该视图）。

用于更改视图的UI分段视图

2 个答案: