ios - UIScrollView 检测用户点击

Question

我正在使用带有 PagingEnabled 的 UIScrollView，在 UIScrollView 中我添加了三个 UIImage。它工作正常。

我想知道如何检测用户是否在 UIImage 中的两个正方形之间点击，例如：在附加的图像中，我如何检测用户是否在正方形 1 和 2 之间点击，或者用户是否在正方形 2 和 3 之间点击？

有任何想法吗？

谢谢。

Answer 1

将手势添加到图像视图

imageView.userInteractionEnabled = YES;
UIPinchGestureRecognizer *pgr = [[UIPinchGestureRecognizer alloc] 
    initWithTarget:self action:@selector(handlePinch:)];
pgr.delegate = self;
[imageView addGestureRecognizer:pgr];
[pgr release];
:
:
- (void)handlePinch:(UIPinchGestureRecognizer *)pinchGestureRecognizer
{
  //handle pinch...
}

Answer 2

为了检测单个或多个水龙头使用UITapGestureRecognizer，它是UIGestureRecognizer. 您不应忘记将该userInteractionEnabled属性设置为YES，因为UIImageView-class 将默认值更改为NO。

self.imageView.userInteractionEnabled = YES;
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(handleTap:)];
// Set the number of taps, if needed
[tapRecognizer setNumberOfTouchesRequired:1];
// and add the recognizer to our imageView
[imageView addGestureRecognizer:tapRecognizer];

- (void)handleTap:(UITapGestureRecognizer *)sender {
    if (sender.state == UIGestureRecognizerStateEnded) {
        // if you want to know, if user tapped between two objects
        // you need to get the coordinates of the tap
        CGPoint point = [sender locationInView:self.imageView];
        // use the point
        NSLog(@"Tap detected, point: x = %f y = %f", point.x, point.y );
       // then you can do something like
       // assuming first square's coordinates: x: 20.f y: 20.f width = 10.f height: 10.f
       // Construct the frames manually
       CGRect firstSquareRect = CGRectMake(20.f, 20.f, 10.f, 10.f);
       CGRect secondSquareRect = CGRectMake(60.f, 10.f, 10.f, 10.f);
       if(CGRectContainsPoint(firstSquareRect, point) == NO && 
          CGRectContainsPoint(secondSquareRect, point) == NO && 
          point.y < (firstSquareRect.origin.y + firstSquareRect.size.height) /* the tap-position is above the second square */ ) {
         // User tapped between the two objects
       }
    }
}