如何让UIImageView具有像UIButton一样的点击效果

先介绍.h文件，直接看代码：

#import <UIKit/UIKit.h>@interface KKClickEffectImageView : UIImageView@end

再看.m文件：

#import "KKClickEffectImageView.h"@implementation KKClickEffectImageView#pragma mark - 点击高亮处理- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {    self.highlighted = YES;}- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {}- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {    self.highlighted = NO;}- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {    self.highlighted = NO;}#pragma mark - 高亮后产生的效果- (void)setHighlighted:(BOOL)highlighted {    [super setHighlighted:highlighted];    if (highlighted) {        self.alpha = 0.5;    }    else {        self.alpha = 1.f;    }}@end