iOS：無法更改UIBarButtonItem的顏色

Question

我基本上有一個ViewController，它是UINavigationController的根ViewController。基本上我有一個UIBarButtonItem，當用戶按下它時，它的色彩應該在紅色和綠色之間切換。但顏色似乎沒有改變。我的代碼：

@interface TestButtonColorViewController(){ 
    BOOL colorMode; 
} 
@end 

@implementation TestButtonColorViewController 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    colorMode = NO; 

    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Change" style:UIBarButtonItemStyleBordered target:self action:@selector(changeColor)]; 


} 

- (void)didReceiveMemoryWarning 
{ 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

- (void)changeColor{ 
    colorMode = !colorMode; 

    if (colorMode) { 
     [[UIBarButtonItem appearanceWhenContainedIn:[UINavigationBar class], nil] setTintColor:[UIColor redColor]]; 
    } 
    else { 
     [[UIBarButtonItem appearanceWhenContainedIn:[UINavigationBar class], nil] setTintColor:[UIColor greenColor]]; 
    } 
} 

Answer 1

由於CSmith：它曾建議，你應該直接設置色調：

- (void)changeColor { 
    colorMode = !colorMode; 

    if (colorMode) { 
     [self.navigationItem.rightBarButtonItem setTintColor:[UIColor redColor]]; 
    } else { 
     [self.navigationItem.rightBarButtonItem setTintColor:[UIColor greenColor]]; 
    } 
}