iphone sdk: finding the direction of scrolling in UIScrollView
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by Alex1987
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Published on 2010-03-30T08:11:23Z
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2010/03/30
8:13 UTC
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I have a UIScrollView with only horizontal scrolling allowed, and I would like to know which direction (left, right) the user scrolls. What I did was to subclass the UIScrollView and override the touchesMoved method:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesMoved:touches withEvent:event];
UITouch *touch = [touches anyObject];
float now = [touch locationInView:self].x;
float before = [touch previousLocationInView:self].x;
NSLog(@"%f %f", before, now);
if (now > before){
right = NO;
NSLog(@"LEFT");
}
else{
right = YES;
NSLog(@"RIGHT");
}
}
But this method sometimes doesn't get called at all when I move. What do you think?
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