UIButton编程代码的问题

创建了一个UIButton，点击之后会显示另一个UIView，测试时我用viewDidLoad中的代码：

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.hard1 = [UIButton buttonWithType:UIButtonTypeCustom];
    [self.hard1 setFrame:CGRectMake(884, 524, 105, 60)]; // set the x,y,width and height based on your specs
    UIImage *buttonImage = [UIImage imageNamed:@"green.jpg"];
    hard1.layer.cornerRadius = 10;
    hard1.clipsToBounds = YES;
    [hard1 addTarget: self
              action: @selector(buttonClicked:)
    forControlEvents: UIControlEventTouchUpInside];
    [self.hard1 setImage:buttonImage forState:UIControlStateNormal];
    [self.view addSubview:self.hard1];
}

再往下：

- (IBAction) buttonClicked: (id)sender
{
    NSLog(@"Tap");
}

但是控制台没有执行点击动作。不知道为什么？

你看看这个是否有帮助：
http://www.2cto.com/kf/201302/188457.html