给图片设置圆角和圆形边框,添加点击事件

    //1.创建图片
    _userImage = [[UIImageView alloc]init];
　　
　　//2.设置图片圆角
    _userImage.layer.cornerRadius  = 33;
    _userImage.layer.masksToBounds = YES;
    
    //3.设置圆形边框
    CALayer *layer    = [_userImage layer];
    layer.borderColor = [[UIColor whiteColor] CGColor];
    layer.borderWidth = 2.0f;
    
    //4.给图片添加点击事件
    _userImage.userInteractionEnabled    = YES;
    UITapGestureRecognizer *userImageTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(userImageAction)];
    [_userImage addGestureRecognizer: userImageTap];