点击按钮后切换图片

//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