UIScrollView not scrollling, or being interactive for that matter - iphone

Question

I have the following hierarchy:
VC -> UIView -> UISCrollView
the UIView happens to be the delegate of the UIScrollView, and owns the UIScrollView as an instance variable.
UIView .h:
#import <UIKit/UIKit.h>
#import "ImageScrollView.h"
#interface Scroller : UIView <UIScrollViewDelegate>{
ImageScrollView *scroller;
}
#end
.m:
#import "Scroller.h"
#implementation Scroller
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
DLog(#"");
[self initScroll];
}
return self;
}
-(void)initScroll{
DLog(#"");
scroller = [[ImageScrollView alloc] initWithFrame:CGRectMake(0.0, 0.0, 200, 200)];
scroller.delegate = self;
[self addSubview:scroller];
}
- (void)scrollViewDidScroll:(UIScrollView *)sender {
// Update the page when more than 50% of the previous/next page is visible
CGFloat pageWidth = self.frame.size.width;
int page = floor((scroller.contentOffset.x - pageWidth / 2) / pageWidth) + 1;
DLog(#"%d",page);
}
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
DLog(#"");
}
Note: as of now, none of the delegate methods get called. I see the UIScrollView on the iphone screen as a black box, however.
#import "ImageScrollView.h"
#implementation ImageScrollView
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
DLog(#"%f %f",frame.size.width,frame.size.height);
[self configUI];
[self configSelf];
}
return self;
}
-(void)configUI{
self.backgroundColor = [UIColor blackColor];
self.contentSize = CGSizeMake(1000, 400);
self.showsHorizontalScrollIndicator = YES;
}
-(void)configSelf{
self.scrollEnabled = YES;
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
DLog(#"");
for (UITouch *touch in touches) {
CGPoint _location = [touch locationInView:touch.view];
[self processTouch:_location];
}
[self.delegate scrollViewDidEndDecelerating:self];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
DLog(#"");
for (UITouch *touch in touches) {
CGPoint _location = [touch locationInView:touch.view];
[self processTouch:_location];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
DLog(#"");
for (UITouch *touch in touches) {
CGPoint _location = [touch locationInView:touch.view];
[self processTouch:_location];
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[self touchesEnded:touches withEvent:event];
}
Note: none of the touchesEnded or touchesMoved methods get called either in the IUScrollViewSubclass.
What am I doing wrong?
This code works however if I assign the view controller as the delegate to the uiscrollview

Answer 1

If I implement your code, it works fine.
To check more closely what is happening, I added this line:
NSLog (#"%#",NSStringFromSelector(_cmd));
at the start of every method.
If I pan inside the scrollView this is the log:
ScrollViewTest1[4155:707] scrollViewDidScroll:
ScrollViewTest1[4155:707] 0
ScrollViewTest1[4155:707] scrollViewDidScroll:
ScrollViewTest1[4155:707] 0
ScrollViewTest1[4155:707] scrollViewDidScroll:
ScrollViewTest1[4155:707] 0
ScrollViewTest1[4155:707] scrollViewDidEndDecelerating:
Your touches methods don't get called as the touches are intercepted by the scrollView's built-in panGestureRecognizer.
If I tap inside the scrollView this is the log:
ScrollViewTest1[4155:707] touchesBegan:withEvent:
ScrollViewTest1[4155:707] processTouch:
ScrollViewTest1[4155:707] scrollViewDidEndDecelerating:
ScrollViewTest1[4155:707] touchesEnded:withEvent:
ScrollViewTest1[4155:707] processTouch:
Touches called as the scrollView isn't grabbing the touch events for it's own gestureRecognizer.