iphone - 如何初始化UIGestureRecognizer？

Question

我想在我的按钮上添加一个手势识别器，以便在用户滑过按钮框架时可以运行代码。如果向上，向右，向左或向下滑动按钮，我也希望此代码有所不同。

-(void)viewDidLoad
{
    [super viewDidLoad];
    UIButton *button=[UIButton buttonWithType:UIButtonTypeRoundedRect];
    button.frame=CGRectMake(0, 0, 100, 100);
    [self.view addSubview:button];
    UIGestureRecognizer *swipe=[[UIGestureRecognizer alloc]initWithTarget:button action:@selector(detectSwipe)];
    [button addGestureRecognizer:swipe];
}

那么，我是否正确执行了initWithTarget:action:？现在，我要如何实现detectSwipe方法？

这是我关于如何实现detectSwipe的想法

          -(IBAction)detectSwipe:(UIButton *)sender
        {
      /* I dont know how to put this in code but i would need something like, 
if (the swipe direction is forward and the swipe is > sender.frame ){ 
[self ForwardSwipeMethod];
    } else if //same thing for right
    else if //same thing for left
    else if //same thing for down

        }

Answer 1

您可能想使用UISwipeGestureRecognizer。通常不应该使用UIGestureRecognizer，除非您将其子类化。您的代码应类似于以下内容。

UISwipeGestureRecognizer *swipe=[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(detectSwipe)];
swipe.direction = UISwipeGestureRecognizerDirectionRight;
[button addGestureRecognizer:swipe];