设置导航栏背景为透明

   我们项目里面一般会用一个公用的导航栏,但是有时候我们在某个控制里面的导航栏,不想用公用的颜色背景,比如这里我们需要透明的背景

  

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    
    for (UIView *aView in self.navigationController.navigationBar.subviews) {
        
        if ([aView isKindOfClass:NSClassFromString(@"_UINavigationBarBackground")]) {
            
            aView.hidden = YES;
            
        }
        
    }
    
}
- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    
    for (UIView *aView in self.navigationController.navigationBar.subviews) {
        
        if ([aView isKindOfClass:NSClassFromString(@"_UINavigationBarBackground")]) {
            aView.hidden = NO;
        }
        
    }
    
}

  

viewWillAppear是弄透明

viewWillDisappear是为了离开该控制器还原为公用的导航栏