需求:

• normal状态下,橙色背景,白色字体
• selected状态下,绿色背景,红色字体

状态效果图.png

1.出现的问题

在normal状态和selected状态下点击button出现一样的高亮效果(都是基于normal状态的),如图所示

highlighted状态下的两种图.png

区别在于adjustsImageWhenHighlighted为YES/NO

2.设置选中状态下的高亮效果

1. 取出selected状态下的背景图片,文字等,赋值给 UIControlStateSelected | UIControlStateHighlighted状态
   UIImage *image = [self.btn backgroundImageForState:UIControlStateSelected];
   [self.btn setBackgroundImage:image forState:UIControlStateSelected | UIControlStateHighlighted];
   NSString *text = [self.btn titleForState:UIControlStateSelected];
   [self.btn setTitle:text forState:UIControlStateSelected | UIControlStateHighlighted];
2. 自定义button,重写系统方法
   Xib和Storyboard中无效
   - (void)setTitle:(NSString *)title forState:(UIControlState)state {
   [super setTitle:title forState:state];
   if (state == UIControlStateSelected) {
   [super setTitle:title forState:UIControlStateSelected | UIControlStateHighlighted];
   }
   }
   - (void)setBackgroundImage:(UIImage *)image forState:(UIControlState)state {
   [super setBackgroundImage:image forState:state];
   if (state == UIControlStateSelected) {
   [self setBackgroundImage:image forState:UIControlStateSelected | UIControlStateHighlighted];
   }
   }

3.禁掉button在selected状态下的highlighted效果

1. 自定义button,重写setHighlighted: 方法
   - (void)setHighlighted:(BOOL)highlighted {
   if (self.selected) {
   [super setHighlighted:NO];
   }else {
   [super setHighlighted:highlighted];
   }
   }

2. UIButton添加Target进行监听,设置highlighted
   [self.btn addTarget:self action:@selector(preventFlicker:) forControlEvents:UIControlEventAllTouchEvents];
   - (void)preventFlicker:(UIButton *)btn {
   if (btn.isSelected) {
   btn.highlighted = NO;
   }
   }

3. 在UIbutton的Category中重写setHighlighted: 方法
   用黑魔法交换方法
   + (void)load {
   Method fromMethod = class_getInstanceMethod([self class], @selector(setHighlighted:));
   Method toMethod = class_getInstanceMethod([self class], @selector(swizzlingSetHighlighted:));

       // 验证
       if (!class_addMethod([self class], @selector(swizzlingSetHighlighted:), method_getImplementation(toMethod), method_getTypeEncoding(toMethod))) {
           method_exchangeImplementations(fromMethod, toMethod);
       }
   }
   
   - (void)swizzlingSetHighlighted:(BOOL)highlighted {
       if (self.isSelected) {
           [self swizzlingSetHighlighted:NO];
       }else {
           [self swizzlingSetHighlighted:highlighted];
       }
   }