How to detect the touch (CGPoint) of a scroll view in its content size in iPhone?

Question

I want to detect the touch (CGPoint) of a scroll view in its content size. If I detect the touch in the scroll I get the CGPoint only with reference to the scroll view frame, but I want the position with reference to content size.

Here is my code

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch* t;
NSLog(@"inside touches began");
if([[event allTouches] count]==1){
    t=[[[event allTouches] allObjects] objectAtIndex:0];
    p1=[t locationInView:scroll];
}

My scroll view frame is (0,0,320,460) and content size is (320,800);

If I scroll my view and touch it at bottom, the CGPoint value obtained is 450 but I want to get as 750 (with reference to content size).

Answer 1

I think what you want is

CGPoint touchInScrollView = [theUITouch locationInView:theScrollView];

If I'm reading my code right. :)

Answer 2

也许您可以使用UIScrollView的contentOffset来计算正确的点？

CGPoint realPoint = CGPointMake( scrollView.contentOffset.x + p1.x, scrollView.contentOffset.y + p1.y );