如何处理多点触控

Question

我正在使用 box2d 在 xcode 中编写一个应用程序。现在我正在使用下面的代码。问题是它只能处理一个触摸事件。如何使我的代码处理所有触摸事件，在本例中检查每次触摸的位置。我还想存储触摸，以便当它们结束时我可以使用正确的代码来结束各个触摸开始的任何内容。

-(void) ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    UITouch *myTouch = [touches anyObject];
    CGPoint location = [myTouch locationInView:[myTouch view]];
    location = [[CCDirector sharedDirector] convertToGL:location];
    b2Vec2 locationWorld = b2Vec2(location.x/PTM_RATIO, location.y/PTM_RATIO);
    CGSize screenSize = [CCDirector sharedDirector].winSize;

    if (locationWorld.x >= screenSize.width*2/5/PTM_RATIO && locationWorld.x <= screenSize.width*3.25/5/PTM_RATIO) {
        //do something
    }
    else if (0 && locationWorld.x <= screenSize.width*2/5/PTM_RATIO) {
        //do something else

    }
}

Answer 1

它应该是这样的：

- (void)ccTouchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
    for (UITouch *touch in touches) 
    {
        if (touch.phase == UITouchPhaseBegan) 
        {
            // Insert code here
        }
    }
}

Answer 2

您可以通过以下方式获取触摸屏幕的手指数量：

NSSet *touchEvents = [event allTouches];

您可以使用 for 循环和单步遍历 touchEvents 来获取每个触摸的单独位置、多次点击等。

Answer 3

除了迭代触摸集之外，您还需要确保视图启用了多点触摸。这可以在 Interface Builder/Xcode 4 中完成

Answer 4

在 COCOS2D-X 中

void LayerHero::ccTouchesEnded(CCSet* touches, CCEvent* event)
{
CCTouch* touch = (CCTouch*)( touches->anyObject() );
CCPoint location = touch->getLocationInView();
location = CCDirector::sharedDirector()->convertToGL(location);
CCSize visibleSize = CCDirector::sharedDirector()->getVisibleSize();

if(location.x<visibleSize.width/2)
{

}
 else if(location.x>visibleSize.width/2)
 {
    CCLOG("We are in the touch2 %f",location.x);

  }
}