将分段控件添加到UINavigationBar的中心

Question

我正在尝试将UISegmentedControl添加到只有一个视图（不是整个视图控制器）的UINavigationBar的中间。我怎么能这样做呢？

我读过的其他答案只允许整个视图控制器包含UINavigationItem作为标题。我需要它只在一个视图上显示。

Answer 1

此代码可以帮助您。

UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:
                                            [NSArray arrayWithObjects:@"Add",@"Delete",
                                             nil]];
    segmentedControl.frame = CGRectMake(0, 0, 80, 30);
    segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar;
    [segmentedControl setWidth:35.0 forSegmentAtIndex:0];
    [segmentedControl setWidth:45.0 forSegmentAtIndex:1];

    [segmentedControl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];
    segmentedControl.momentary = YES;

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

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

此代码的结果是

修改

可行的确切代码：

UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:
                                            [NSArray arrayWithObjects:@"Add",@"Delete",
                                             nil]];
    segmentedControl.frame = CGRectMake(0, 0, 80, 30);
    segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar;
    [segmentedControl setWidth:35.0 forSegmentAtIndex:0];
    [segmentedControl setWidth:45.0 forSegmentAtIndex:1];

    [segmentedControl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];
    segmentedControl.momentary = YES;

    self.navigationItem.titleView = segmentedControl;

Answer 2

您可以将UISegmentedControl作为SubView添加到导航栏。

NSArray *arrayOfItems = [[NSArray alloc] initWithObjects:@"A",@"B",@"C", nil];
UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:arrayOfItems];
segmentedControl.frame=CGRectMake(60, 0, 200, 44);
[self.navigationController.navigationBar addSubview:segmentedControl];

Answer 3

如果要在任何视图中心添加UISegmentedControl，而不仅仅是UINavigationView：

UISegmentedControl *segmentedTab = [[UISegmentedControl alloc] initWithItems:[NSArray arrayWithObjects:@"a", @"b", @"c", nil]];
segmentedTab.center = CGPointMake(segmentedView.frame.size.width / 2, segmentedView.frame.size.height / 2);
[self.segmentedView addSubview:segmentedTab];

其中segmentedView是一个包含我们的UISegmentedControl的视图。