xcode UIButton 作为 UINavigationbar 按钮

UIButton as UINavigationbar button

提问by Rupert

I have a Tab bar application. and in one of the tab bars I have a navigation contorller. Im trying to set a UIButton with an image as the right button the navigation bar.

我有一个标签栏应用程序。在其中一个标签栏中，我有一个导航控制器。我试图将带有图像的 UIButton 设置为导航栏的右侧按钮。

    UIButton *refreshButton = [[UIButton alloc] init];
    [refreshButton setImage:[UIImage imageNamed:@"refresh_icon.png"] forState:UIControlStateNormal];
    [refreshButton addTarget:self action:@selector(refreshSection) forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithCustomView:refreshButton];
    //[rightButton setImage:[UIImage imageNamed:@"refresh_icon.png"]]; << DOESN'T WORK EITHER  
    self.navigationItem.rightBarButtonItem = rightButton;
    [refreshButton release];
    [rightButton release];

but the image doesn't show up. I get an invisible button.

但图像不显示。我得到一个隐形按钮。

EDIT:I want the button style to be plain or background to be transparent, so that only the image shows. Hence I am using a UIbutton instead of using a UIBarButton directly.

编辑：我希望按钮样​​式为纯色或背景为透明，以便仅显示图像。因此我使用 UIbutton 而不是直接使用 UIBarButton。

回答by Yannick Compernol

You don't have to create a UIButtonand use it as custom view in the UIBarButtonItem. You can create a UIBarButtonItemdirectly with an image:

您不必创建一个UIButton并将其用作UIBarButtonItem. 您可以UIBarButtonItem直接使用图像创建：

UIImage *myImage = [UIImage imageNamed:@"myImage.png"];
UIBarButtonItem *button = [[UIBarButtonItem alloc] initWithImage:myImage style:UIBarButtonItemStyleBordered target:self action:@selector(refreshSection)];  
self.navigationItem.rightBarButtonItem = button;    
[button release];

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Updated, according to comments

根据评论更新

Use a UIImageViewas custom view in the UIBarButtonItem:

在 中使用UIImageView作为自定义视图UIBarButtonItem：

UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"myImage.png"]];
UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithCustomView:imageView];
self.navigationItem.rightBarButtonItem = rightButton;
[imageView release];
[rightButton release];

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Updated

更新

Tried the last approach and while this does visually look like you want it to, I can't seem to get it to handle taps. Although the target and action has been set.

尝试了最后一种方法，虽然这在视觉上看起来像你想要的那样，但我似乎无法让它处理水龙头。虽然目标和行动已经确定。

--

——

Final update

最终更新

I've gotten your initial code in the question up & running. The reason the image is not showing, is because you haven't set the frame of the button. Once you set the frame, the image is shown in the navigation bar.

我已经启动并运行了问题中的初始代码。图像未显示的原因是因为您尚未设置按钮的框架。设置框架后，图像将显示在导航栏中。

Here's my snippet I used & tested:

这是我使用和测试的片段：

UIImage *myImage = [UIImage imageNamed:@"paw.png"];
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
[myButton setImage:myImage forState:UIControlStateNormal];
myButton.showsTouchWhenHighlighted = YES;
myButton.frame = CGRectMake(0.0, 0.0, myImage.size.width, myImage.size.height);

[myButton addTarget:self action:@selector(tapped:) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithCustomView:myButton];
self.navigationItem.rightBarButtonItem = rightButton;

[rightButton release];
[myButton release];

Note: I have set the showsTouchWhenHighlightedproperty of the UIButtonto visually hightlight the button when it is pressed.

注意：我已将 的showsTouchWhenHighlighted属性设置为在UIButton按下按钮时在视觉上突出显示按钮。

回答by Rupert

I ended up doing this

我最终这样做了

    UIButton *refreshButton = [[UIButton alloc] initWithFrame:CGRectMake(292, 9, 27, 27)];
    [refreshButton setImage:[UIImage imageNamed:@"refresh_icon.png"] forState:UIControlStateNormal];
    [refreshButton addTarget:self action:@selector(refresh) forControlEvents:UIControlEventTouchUpInside];
    [self.navigationController.navigationBar addSubview:refreshButton];
    [refreshButton release];

It works fine now but I am not really sure if this is the right way of doing it.

它现在工作正常，但我不确定这是否是正确的做法。