iOS常见问题之动态修改UINavigationController的rightBarButtonItem的title

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1.初始化

在viewDidLoad里，为navigationItem添加名称为“添加分栏”的按钮

- (void)viewDidLoad
{
    [super viewDidLoad];
// Do any additional setup after loading the view.
    
    self.navigationItem.rightBarButtonItem.title = @"添加分栏";
    [self.navigationItem.rightBarButtonItem initWithBarButtonSystemItem:UIBarButtonSystemItemUndo
                                                                 target:self
                                                                 action:@selector(myAction)];
    
    
}

2.试图更改按钮名称失败

-(void)onSelectionChanged:(id)selection
{
    self.navigationItem.rightBarButtonItem.title = @"编辑";
     
}

3.原因分析

为何直接设置backBarButtonItem的title无效呢？

查看苹果文档UIBarButtonItem的父类UIBarItem的title属性描述：

You should set this property before adding the item to a bar. The default value is nil.故无法修改其title，只能重置这个控件本身。

4.正确代码

4.1思路一

self.navigationItem.rightBarButtonItem.title = @"编辑";

[self.navigationItem.rightBarButtonItem initWithBarButtonSystemItem:UIBarButtonSystemItemUndo
								target:self
								action:@selector(myAction)];

4.1思路二

UIBarButtonItem *temporaryBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemUndo
                                                                    target:self
                                                                    action:@selector(changeWellColumnAction)];
    temporaryBarButtonItem.title = @"编辑";
    self.navigationItem.rightBarButtonItem = temporaryBarButtonItem;
    [temporaryBarButtonItem release];

iOS常见问题之动态修改UINavigationController的rightBarButtonItem的title

标签：os   io   ar   for   div   问题   cti   代码   html   

原文地址：http://blog.csdn.net/wanglei9876/article/details/38932993