objective-c - 如何将图像添加到 UIBarButtonItem？

Question

我创建了一个自定义按钮并将其应用于 UIbarbuttonitem。没有错误，但导航栏上没有显示任何内容:(这是我的代码-

    //create a custom button
    UIImage *image = [UIImage imageNamed:@"TESTButton.png"];
    UIButton *myCustomButton = [UIButton buttonWithType:UIButtonTypeCustom];
    myCustomButton.bounds = CGRectMake( 0, 0, image.size.width, image.size.height );    
    [myCustomButton setImage:image forState:UIControlStateNormal];
    [myCustomButton addTarget:nil action:@selector(goBack:) forControlEvents:UIControlEventTouchUpInside];


    UIBarButtonItem *button = [[UIBarButtonItem alloc] initWithCustomView:myCustomButton];
    self.navigationItem.leftBarButtonItem = button;
    self.navigationController.navigationBar.barStyle = UIBarStyleDefault;

    [button release];
    [myCustomButton release];
    [image release];
    [navID release];

谁能修复我的代码？:)

Answer 1

从文档：

initWithImage:style:target:action:

试试看。

Answer 2

要设置任何具有正确颜色的图像，请使用 UIButton，设置“状态图像”，然后使用customView创建UIBarButtonItem

UIImage *btnImage = [UIImage imageNamed:@"button"];
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
btn.bounds = CGRectMake( 0, 0, btnImage.size.width, btnImage.size.height );
[btn addTarget:self action:@selector(action:) forControlEvents:UIControlEventTouchDown];
[btn setImage:btnImage forState:UIControlStateNormal];
_buttonItem = [[UIBarButtonItem alloc] initWithCustomView:btn];

Answer 3

最简单的方法之一是：

UIBarButtonItem *button2 = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"backk.png"] style:UIBarButtonItemStylePlain target:self action:@selector(backBtn:)];
self.navigationItem.leftBarButtonItem = button2;

行动方法：

- (IBAction)backBtn:(id)sender
{
    [self.navigationController popViewControllerAnimated:YES];
}