使用 UIPanGestureRecognizer，有没有办法只执行如此频繁的操作，例如在平移 x 个像素之后？

现在，我的 UIPanGestureRecognizer 可以识别每一个平移，这很好而且必要，但是当我使用它作为滑动手势来增加和减少变量的值时，在该方法中我只想经常执行操作。如果我每次检测到它时就增加 1，那么该值就会上升得太快。

有没有办法做到每 10 个像素的平移执行此操作或类似的操作？

您正在寻找translationInView: http://developer.apple.com/library/ios/documentation/uikit/reference/UIPanGestureRecognizer_Class/Reference/Reference.html#//apple_ref/occ/instm/UIPanGestureRecognizer/translationInView%3a，它告诉您平移已经前进了多远，并且可以根据您的最小距离进行测试。此解决方案不涵盖您在一个方向上来回移动等于最小距离的情况，但如果这对您的场景很重要，那么添加起来并不难。

#define kMinimumPanDistance 100.0f

UIPanGestureRecognizer *recognizer;
CGPoint lastRecognizedInterval;

- (void)viewDidLoad {
    [super viewDidLoad];

    recognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(didRecognizePan:)];
    [self.view addGestureRecognizer:recognizer];
}

- (void)didRecognizePan:(UIPanGestureRecognizer*)sender {
    CGPoint thisInterval = [recognizer translationInView:self.view];

    if (abs(lastRecognizedInterval.x - thisInterval.x) > kMinimumPanDistance ||
        abs(lastRecognizedInterval.y - thisInterval.y) > kMinimumPanDistance) {

        lastRecognizedInterval = thisInterval;

        // you would add your method call here
    }
}