酒吧按钮不显示

Question

我想使用自定义barbutton，将有一些图像。 我正在做如下code.but barbutton不显示。

UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom]; 
[button setImage:[UIImage imageNamed:@"icon.png"] forState:UIControlStateNormal]; 

[button addTarget:self action:@selector(nowPlayingButtonClicked) forControlEvents:UIControlEventTouchUpInside]; 

nowPlaying = [[UIBarButtonItem alloc] initWithCustomView:button]; 
nowPlaying.action = @selector(nowPlayingButtonClicked); 
nowPlaying.target = self; 

self.navigationItem.rightBarButtonItem = nowPlaying; 

Answer 1

，你必须为你添加到BarButton

button.frame = CGRectMake(0, 0, 50, 30); 

按钮框架

Answer 2

你必须给图像的状态选择和正常。那么它会出现在你身上。这只是一个提示。但尝试一下。

UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom]; 
[button setImage:[UIImage imageNamed:@"icon.png"] forState:UIControlStateNormal]; 
[button setImage:[UIImage imageNamed:@"icon_pressed.png"] forState:UIControlStateSelected]; 

[button addTarget:self action:@selector(nowPlayingButtonClicked) forControlEvents:UIControlEventTouchUpInside]; 

nowPlaying = [[UIBarButtonItem alloc] initWithCustomView:button]; 
self.navigationItem.rightBarButtonItem = nowPlaying;