iphone - 从 UINavigationBar 中的按钮中删除发光效果

Question

如何去除导航栏按钮的光泽/光泽效果？如果我使用自定义图像自定义导航栏，按钮不受影响，我可以删除它们的效果(线条和光泽)，或者为整个按钮定义一个十六进制颜色代码，甚至为它们定义一个自定义图像？

Answer 1

我刚刚经历了解决这个问题的过程。基本上，您需要创建自定义的可拉伸(stretch)图像并将它们用作按钮的背景以消除光泽。替换 UINavigationController 中的后退按钮有点困难。为此，我使用 UINavigationControllerDelegate 将默认后退按钮替换为我的自定义按钮。

这是一些代码:

1. 在 UIBarButtonItem 上创建一个类别，用于创建您的自定义按钮。这是我的。我使用这个类别来自定义常规栏按钮和后退按钮:

   @interface UIBarButtonItem (UIBarButtonItem_customBackground)
   
   + (id) customBarButtonWithTitle:(NSString *)title target:(id)target selector:(SEL)selector;
   + (id) customBackButtonWithTitle:(NSString *)title target:(id)target selector:(SEL)selector;
   
   @end
   
   @implementation UIBarButtonItem (UIBarButtonItem_customBackground)
   
   + (id) customButtonWithImageNamed:(NSString *)imageName selectedImageNamed:(NSString *)selectedImageName leftCapWidth:(CGFloat)leftCapWidth edgeInsets:(UIEdgeInsets)edgeInsets title:(NSString *)title target:(id)target selector:(SEL)selector {
       UIButton* customButton = [UIButton buttonWithType:UIButtonTypeCustom];
       [customButton addTarget:target action:selector forControlEvents:UIControlEventTouchUpInside];
       customButton.titleLabel.font = [UIFont boldSystemFontOfSize:12.0f];
       customButton.titleLabel.shadowColor = [UIColor colorWithRed:0.0f/255.0f green:0.0f/255.0f blue:0.0f/255.0f alpha:0.25f];
       customButton.titleLabel.shadowOffset = CGSizeMake(0.0f, -1.0f);
       customButton.titleLabel.lineBreakMode = UILineBreakModeTailTruncation;
       customButton.titleEdgeInsets = edgeInsets;
       UIImage* navButtonBackgroundImage = [[UIImage imageNamed:imageName] stretchableImageWithLeftCapWidth:leftCapWidth topCapHeight:0.0f];
       UIImage* navButtonPressedBackgroundImage = [[UIImage imageNamed:selectedImageName] stretchableImageWithLeftCapWidth:leftCapWidth topCapHeight:0.0f];
       [customButton setBackgroundImage:navButtonBackgroundImage forState:UIControlStateNormal];
       [customButton setTitle:title forState:UIControlStateNormal];
       [customButton setBackgroundImage:navButtonPressedBackgroundImage forState:UIControlStateHighlighted];
       [customButton setBackgroundImage:navButtonPressedBackgroundImage forState:UIControlStateSelected];
   
       CGSize size = CGSizeMake(30.0f, 30.0f);
       if (title != nil) {
           size = [[NSString stringWithString:title] sizeWithFont:customButton.titleLabel.font];
       }
       customButton.frame = CGRectMake(0.0f, 0.0f, size.width + 20.0f, 30.0f);
       customButton.layer.shouldRasterize = YES;
       customButton.layer.rasterizationScale = [[UIScreen mainScreen] scale];
       return [[[UIBarButtonItem alloc] initWithCustomView:customButton] autorelease];
   }
   
   + (id) customBarButtonWithTitle:(NSString *)title target:(id)target selector:(SEL)selector {
       return [self customButtonWithImageNamed:@"navButtonBG.png" 
                    selectedImageNamed:@"navButtonPressedBG.png" 
                          leftCapWidth:6.0f 
                            edgeInsets:UIEdgeInsetsMake(0.0f, 5.0f, 0.0f, 5.0f) 
                                 title:title 
                                target:target 
                              selector:selector];
   }
   
   + (id) customBackButtonWithTitle:(NSString *)title target:(id)target selector:(SEL)selector {    
       return [self customButtonWithImageNamed:@"backButtonBG.png" 
                    selectedImageNamed:@"backButtonPressedBG.png" 
                          leftCapWidth:12.0f 
                            edgeInsets:UIEdgeInsetsMake(0.0f, 11.0f, 0.0f, 5.0f) 
                                 title:title 
                                target:target 
                              selector:selector];
   }
   
   @end
   

2. 将按钮添加到您的 UINavigationBar

   UIBarButtonItem* logoutButton = [UIBarButtonItem customBarButtonWithTitle:@"Logout" target:self selector:@selector(logout)];
   self.navigationItem.rightBarButtonItem = logoutButton;
   

3. 如果您还想替换 UINavigationController 的后退按钮，请设置 UINavigationControllerDelegate 并实现 willShowViewController 方法，如下所示:

   - (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
       if([navigationController.viewControllers count ] > 1) {
           UIViewController* backViewController = [navigationController.viewControllers objectAtIndex:(navigationController.viewControllers.count - 2)];
           NSString* backText = backViewController.title;
           UIBarButtonItem* newBackButton = [UIBarButtonItem customBackButtonWithTitle:backText target:navigationController selector:@selector(popViewControllerAnimated:)];
           viewController.navigationItem.leftBarButtonItem = newBackButton;
           viewController.navigationItem.hidesBackButton = YES;
       }
   }
   

4. 这是我正在使用的可拉伸(stretch)图像:

   • 后退按钮:按下:
   • 常规按钮:按下: