关于iPhone多点触控

时间:2022-08-05 07:01:23

虽然这个问题很简单,但是对于我这接触两天的菜鸟来说也弄了很久,网上又找不到相关的解决方法,避免其他人和我一样,还是记录一下

一般网上找到的教程是这么教:

-(void )touchesBegin:(NSSet *)touches withEvent:(UIEvent *)event

{   

    NSArray *twoTouches = [touches allObjects];
UITouch *firstTouch = [twoTouches objectAtIndex:];
UITouch *secondTouch = [twoTouches objectAtIndex:];
CGPoint point1 =[touch1 locationInView:[touch1 view]];
CGPoint point2 =[touch2 locationInView:[touch2 view]]; NSLog(@"point1:%@",NSStringFromCGPoint(point1));
NSLog(@"point2:%@",NSStringFromCGPoint(point2));
}

但是这里面首先NSArray这个累不知道能不能去NSSet这个类的东西

接着最主要的问题是touchesBegin这个方法在你第一只手指触碰就立即触发这方法。

所以你想去两个手指的话这肯定不行,虽然编译器不会报错,但是一碰就死机

其实只要改个方法就行,用touchesMoved

-(void )touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSSet *allTouches = [event allTouches];
UITouch *touch1 = [[allTouches allObjects] objectAtIndex:];
UITouch *touch2 = [[allTouches allObjects] objectAtIndex:]; CGPoint point1 =[touch1 locationInView:[touch1 view]];
CGPoint point2 =[touch2 locationInView:[touch2 view]]; NSLog(@"point1:%@",NSStringFromCGPoint(point1));
NSLog(@"point2:%@",NSStringFromCGPoint(point2));
}

http://www.cnblogs.com/roucheng/