点击按钮后切换图片

点击按钮，在下面2个图片中切换：

  

//只需要更改m文件代码。

typedef enum
{
    kButtonStart = 1, // 按钮tag=1
    kButtonStop,      // 按钮tag=2
}kButtonStatus;

@implementation ViewController

// other codes
// ...

// 通过按钮的tag进行图片切换
- (IBAction)startBtnDidClick:(UIButton *)sender {
    if (sender.tag == kButtonStart)
    {
        [sender setImage:[UIImage imageNamed:@"pause"] forState:UIControlStateNormal];
        sender.tag = kButtonStop;
    }
    else
    {
        [sender setImage:[UIImage imageNamed:@"start"] forState:UIControlStateNormal];
        sender.tag = kButtonStart;
    }
}

@end