Question

这是启用了多个触摸的视图的touchesBegan方法。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch* touch = [touches anyObject];
    if ([touches count] > 1)
        NSLog(@"multi touches: %d fingers", [touches count]);

    NSUInteger numTaps = [touch tapCount];

    if (numTaps == 1) {
        NSLog(@"single tap");
    } else {
        NSLog(@"multi tap: %d", numTaps);
    }
}

我似乎永远不会记录多点触控。只需单击和双击。我错误地认为它就像接触计数一样容易吗？

Answer 1

您应该在视图上将multipleTouchEnabled属性设置为YES，以便让它向您发送多个UITouch个对象。

除此之外，只传递了更改的UITouch个对象。如果您触摸某个位置并且不移动手指，之后触摸另一个位置，则只会传递新的触摸对象。您应该在UIEvent对象中查询视图中的所有活动触摸：

[event touchesForView:self]

Answer 2

我尝试了三种不同的方式，只有一种可以返回两到五个手指点击。获胜机制是NSSet * touch = [event allTouches];

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
        UITouch* touch = [touches anyObject];
    // the next line will not ever return a multiple tap
    if ([touches count] > 1)
        NSLog(@"multi-touches %d", [touches count]);
    // the next line will return up to 5 (verified) simultaneous taps (maybe more)
        NSSet *touch2 = [event allTouches];
    if ([touch2 count] > 1)
        NSLog(@"multi-touches2 %d", [touch2 count]);
    // the next line only returns 1 tap
        NSSet *touch3 = [event touchesForView:self];
    if ([touch3 count] > 1)
        NSLog(@"multi-touches2 %d", [touch3 count]);
}

Answer 3

获胜机制？有错误和vars甚至没有被使用？

不兼容的Objective-C类型'struct AViewController *'，当从不同的Objective-C类型传递'touchesForView：'的参数1时，期望'struct UIView *'

AViewController.m:64：未使用的变量'touch'

我本来应该能够通过这种方式检测多指点击吗？

3 个答案: