分段按钮未显示在 iPhone 的导航栏上

Posted 2023-03-15

【中文标题】分段按钮未显示在 iPhone 的导航栏上

【英文标题】：Segment Button is not displaying on the navigation bar in iphone

【发布时间】：2011-05-30 08:55:15

【问题描述】：

你好 我在导航栏上显示分段按钮时遇到问题 我试试这段代码它不起作用 我有标签栏为了调用这个标签栏，我使用 此代码 TabBar 工作正常，但导航栏上的 Button 未显示

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
    UITabBarController *tabcontroller = [[UITabBarController alloc] init];

    UITabBarController *vc1 = [[TMapViewController alloc] init];
    UITabBarController *vc2 = [[TShareController alloc]init];
    UITabBarController *vc3 = [[TSpeedometerController alloc]init];
    UITabBarController *vc4 = [[TReviewsController alloc]init];
    NSArray *viewControllers = [NSArray arrayWithObjects:vc1,vc2,vc3,vc4,nil];



    [tabcontroller setViewControllers:viewControllers];

    [vc1 release];
    [vc2 release];
    [vc3 release];
    [vc4 release];

    [self.navigationController pushViewController: tabcontroller animated: YES];

然后将此代码放入 TMapViewController.m 以进行调用 导航栏上的按钮

-(id)init 

    UITabBarItem *tbi = [self tabBarItem];
    [tbi setTitle:@"Map"];
    UIImage *i = [UIImage imageNamed:@"mapper_f.png"];
    [tbi setImage:i];


    UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:
                                            [NSArray arrayWithObjects:
                                             [UIImage imageNamed:@"Activitieslist.png"],

                                             nil]];
    [segmentedControl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];
    segmentedControl.frame = CGRectMake(0, 0, 50, 35);
    segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar;
    segmentedControl.momentary = YES;

    UIBarButtonItem *segmentBarItem = [[UIBarButtonItem alloc] initWithCustomView:segmentedControl];
    [segmentedControl release];

    self.navigationItem.rightBarButtonItem = segmentBarItem;
    [segmentBarItem release];

    return self;

我在 - (void)viewDidLoad [超级viewDidLoad];

UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:
                                        [NSArray arrayWithObjects:
                                         [UIImage imageNamed:@"Activitieslist.png"],

                                         nil]];
[segmentedControl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];
segmentedControl.frame = CGRectMake(0, 0, 50, 35);
segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar;
segmentedControl.momentary = YES;

UIBarButtonItem *segmentBarItem = [[UIBarButtonItem alloc] initWithCustomView:segmentedControl];
[segmentedControl release];

self.navigationItem.rightBarButtonItem = segmentBarItem;
[segmentBarItem release];
[[self.navigationBar topItem] setTitleView:segmentedControl]; 
[[[self.navigationBar topItem] titleView] setUserInteractionEnabled:YES]; 



TLocationManager *manager = [[TLocationManager alloc] init];
self.locationManager = manager;
self.locationManager.delegate = self;
[manager release];

TMapRoutes *routes = [[TMapRoutes alloc] init];
self.mapRoutes = routes;
self.mapRoutes.mapView = self.myMapView;
[routes release];

self.myMapView.delegate = self;

/* Run the simulator */
[locationManager startUpdatingLocation];

即使它不起作用，它也会给我同样的错误。 提前致谢 哈里什

【问题讨论】：

我认为我没有正确解决您的问题。抱歉，我不能在这里提供更多帮助。

当我不使用选项卡时，它会显示 segmentBarItem >这意味着当我使用导航直接调用另一个视图时，推送视图认为它的工作是显示段项，但是当调用所有选项卡项时它不显示段项，但 Tabbar 正在工作

【参考方案1】：

设置为[self.navigationBar titleView:segmentedControl]

-(void)loadView  
 UITabBarItem *tbi = [self tabBarItem];
    [tbi setTitle:@"Map"];
    UIImage *i = [UIImage imageNamed:@"mapper_f.png"];
    [tbi setImage:i];

UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:
                                        [NSArray arrayWithObjects:
                                         [UIImage imageNamed:@"Activitieslist.png"],

                                         nil]];
[segmentedControl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];
segmentedControl.frame = CGRectMake(0, 0, 50, 35);
segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar;
segmentedControl.momentary = YES;

UIBarButtonItem *segmentBarItem = [[UIBarButtonItem alloc] initWithCustomView:segmentedControl];
[segmentedControl release];

[[self.navigationBar topItem] setTitleView:segmentedControl]; [[[self.navigationBAr topItem] titleView] setUserInteractionEnabled:YES];
[segmentBarItem release];

【讨论】：

我在 -(id)init 方法中使用了这个所有代码都是这个 [self.navigationBar titleView:segmentedControl]; 它给了我对成员“navigationBar”的错误请求，而不是结构或联合

试试这个方法，[[self.navigationBar topItem] setTitleView:segmentedControl]; [[[self.navigationBAr topItem] titleView] setUserInteractionEnabled:YES];

不要写在 init 方法中。在 loadview 方法中编写整个代码。

@Anand 看上面我做出改变

我想说的是。在 init 方法中不会创建导航控制器，它将在 loadview 中创建，并且您正在尝试为其设置对象。因此你得到了错误。