ios - 将刷新按钮添加到导航栏

Question

大家好，如果您可以查看下面的代码然后提供一些帮助，我很难尝试让这个导航栏包含一个刷新按钮，这是我的原始代码以及我找到的 UIBarbutton 片段来自谷歌上另一个用户项目的刷新按钮。我遇到了以下错误:

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self.tableView setBackgroundView:nil];
    self.tableView.backgroundColor = [ColorHelper charcoalBackgroundImage];
    UIBarButtonItem *refresh = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(refresh:)];
    self.navigationItem.leftBarButtonItem = refresh;
    // [button release]; remove this line if you're using ARC
}
- (void) refresh
{

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

Answer 1

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self.tableView setBackgroundView:nil];
    self.tableView.backgroundColor = [ColorHelper charcoalBackgroundImage];

    UIBarButtonItem *button = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(refresh:)];
    self.navigationItem.rightBarButtonItem = button;
}

这样写你的方法是因为你在调用中传递了 UIBarButton 对象。

- (void) refresh:(id)sender
{

}

或

UIBarButtonItem *button = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(refresh)];