在 UINavigationbar 中添加栏按钮

Question

我是 iPhone 开发者的新手，

我想在导航栏上的后退按钮旁边再添加一个按钮，我正在使用导航控制器，所以后退按钮已经在左侧。在最右侧，我使用

添加了一个按钮

self.navigationItem.rightBarButtonItem = ModeButton;

但是当我写的时候，

self.navigationItem.leftBarButtonItem = NewButton;

NewButton 覆盖了我的后退按钮，我想将我的新按钮放在后退按钮旁边。

我们将不胜感激。

Answer 1

UINavigationItem 有一个属性leftItemsSupplementBackButton，你可以使用它。

leftItemsSupplementBackButton 一个布尔值，指示除了后退按钮之外是否显示左侧项目。

@property BOOL leftItemsSupplementBackButton

讨论 通常，自定义左栏按钮项目的存在会导致移除后退按钮以支持自定义项目。将此属性设置为 YES 会导致 leftBarButtonItems 或 leftBarButtonItem 属性中的项目显示在后退按钮的右侧——也就是说，它们显示在后退按钮的旁边，而不是代替后退按钮。当设置为 NO 时，将显示这些属性中的项目而不是后退按钮。此属性的默认值为 NO。

来自UINavigationController Class Reference。

UIBarButtonItem *leftBarButtonItem =[[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(logout)];
self.navigationItem.leftBarButtonItem = leftBarButtonItem;
self.navigationItem.leftItemsSupplementBackButton = YES;

Answer 2

我认为你应该有一个灵活的空间让它不与其他空间重叠，也许这样的东西应该让你开始。

    UIBarButtonItem *back = [[UIBarButtonItem alloc] initWithTitle:@"Back" style:UIBarButtonItemStyleBordered target:self action:@selector(Back:)];
    UIBarButtonItem *flexibleSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
    UIBarButtonItem *newButton = [[UIBarButtonItem alloc] initWithTitle:@"newButton" style:UIBarButtonItemStyleBordered target:self action:@selector(newButtonMethod:)];

    NSArray *navBarItems = [[NSArray alloc] initWithObjects:back, flexibleSpace, newButton, nil];

编辑：

NSMutableArray* buttons = [[NSMutableArray alloc] initWithCapacity:3];  
UIBarButtonItem *back = [[UIBarButtonItem alloc] initWithTitle:@"Back" style:UIBarButtonItemStyleBordered target:self action:@selector(Back:)];
[buttons addObject:back];
    UIBarButtonItem *flexibleSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
[buttons addObject:flexibleSpace];
    UIBarButtonItem *newButton = [[UIBarButtonItem alloc] initWithTitle:@"newButton" style:UIBarButtonItemStyleBordered target:self action:@selector(newButtonMethod:)];
[buttons addObject:newButton];

UIToolbar* myToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 100, 45)];
        [myToolbar setTintColor:[self.navigationController.navigationBar tintColor]];
 [myToolbar setItems:buttons animated:NO];

UIBarButtonItem *myButton = [[UIBarButtonItem alloc] initWithCustomView:myToolbar];

self.navigationItem.leftBarButtonItem = myButton;

Answer 3

创建一个包含两个按钮的自定义视图，然后按如下方式创建条形按钮项：

UIBarButtonItem *leftBarButtonItem =[[UIBarButtonItem alloc] initWithCustomView:userCustomView];

self.navigationItem.leftBarButtonItem = leftBarButtonItem;

编辑： 下面的代码只是一个如何创建两个按钮的示例，

UIView *customView = [[UIView alloc] init];
customView.frame = CGRectMake(0, 0, 100, 40);

UIButton *button1 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button1 setTitle:@"Add" forState:UIControlStateNormal];
button1.frame = CGRectMake(0, 0, 50, 40);

UIButton *button2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button2 setTitle:@"del" forState:UIControlStateNormal];
button2.frame = CGRectMake(60, 0, 50, 40);
[customView  addSubview:button2];
[customView addSubview:button1];

UIBarButtonItem *barItem =[[UIBarButtonItem alloc] initWithCustomView:customView];


self.navigationItem.leftBarButtonItem = barItem;

Answer 4

为了实现这一点，您必须创建一个自定义UIBarButtonItem。答案是，您必须分别放置 BackButton（用户定义）和 NewButton 这两个按钮，如下所示：

UIView *viewForLeftBarButton = [[UIView alloc] initWithFrame:CGRectMake(5, 5, 100, 35)];
[viewForLeftBarButton addSubview:BackButton];
[viewForLeftBarButton addSubview:NewButton];

UIBarButtonItem *leftBarButtonItem =[[UIBarButtonItem alloc] initWithCustomView:viewForLeftBarButton];

self.navigationItem.leftBarButtonItem = leftBarButtonItem;