一行代码实现 按钮的选中与反选

记录一行代码 实现按钮的选择 以及反选
实现旋转效果

 sender.selected =  !sender.selected;

注意点:
要设置 按钮的默认selected 是其有个初值

简单示例 代码如下

- (IBAction)btnTransForm:(UIButton*)sender {

    sender.selected =  !sender.selected;

    if (sender.selected) {
        [UIView animateWithDuration:0.2 animations:^{
            sender.transform =  CGAffineTransformMakeRotation(M_PI_4);
        }];
    }else{
        [UIView animateWithDuration:0.2 animations:^{
            sender.transform = CGAffineTransformIdentity;
        }];
    }

}