Question

Before describing my problem a very basic question,is there a way can we return UIScrollView object from this method

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView

Now my problem is, I have a parent scrollview with multiple child scrollview inside it(all horizontal and paging enabled).

Each child scrollview has an ImageView. I am getting zoomScale factor from server and based on the image, I have to zoom it, The problem is when I try to zoom a child scrollView which has image inside it,it only zooms the last child scrollview.

So I think, I need to find out a way where we can return a scrollview form the above written delegate.

Anyone an idea how to solve this?

---

THis is UIView Class and i added scrollView and image on this and returned imageView For scrollView Delegate

SAMPLE CODE:

     - (id)initWithFrame:(CGRect)frame image:(UIImage *)image
{
    self = [super initWithFrame:frame];
    if (self) {

        self.backgroundColor=[UIColor yellowColor];      
        self.imageView = [[UIImageView alloc] initWithImage:image];
        self.imageView.tag = VIEW_FOR_ZOOM_TAG;
        self.imageView.frame=frame;//CGRectMake(8,8 ,305, 400);
        [self.imageView setContentMode:UIViewContentModeScaleAspectFit];


        self.scrollView = [[UIScrollView alloc] initWithFrame:frame];
        self.scrollView.minimumZoomScale = 0.4f;
        self.scrollView.maximumZoomScale = 2.0f;
        self.scrollView.backgroundColor=[UIColor redColor];
        self.scrollView.zoomScale = 1.0f;
        self.scrollView.contentSize = self.imageView.bounds.size;
        self.scrollView.delegate = self;
        self.scrollView.showsHorizontalScrollIndicator = NO;
        self.scrollView.showsVerticalScrollIndicator = NO;
        [self.scrollView setCanCancelContentTouches:NO];
        [self.scrollView addSubview:self.imageView];
        [self addSubview:self.scrollView];

        NSLog(@"ScrollViewPostion %f",self.scrollView.frame.origin.x);
    }
    return self;
}

#pragma -mark
#pragma -mark ScrollViewDelegates
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
    return [scrollView viewWithTag:VIEW_FOR_ZOOM_TAG];
}

And in my main viewController class i am doing this but its not adding all the images properly in the scrollview

 NSLog(@"Inner scrollFrame and content size %f %f",innerScrollFrame.origin.x,mainScrollView.contentSize.width);
    JoinSeeSubView *subView=[[JoinSeeSubView alloc] initWithFrame:innerScrollFrame image:img];
    [self.mainScrollView addSubview:subView];


        if (i < [self.allUrlArray count]-1) {
            innerScrollFrame.origin.x += innerScrollFrame.size.width;
    }
    i++;
    mainScrollView.contentSize = CGSizeMake(innerScrollFrame.origin.x + innerScrollFrame.size.width, mainScrollView.bounds.size.height);

Answer 1

In case the above approach didn’t help someone really in need,I solved this problem in a different way,but not sure if it is correct way to do this.

So instead of creating a new class which extends UIView,I create and array and store all the objects of inner scrollview in that array.So my code look something like

       UIScrollView *pageScrollView = [[UIScrollView alloc] initWithFrame:innerScrollFrame];
        pageScrollView.minimumZoomScale = 0.4f;
        pageScrollView.maximumZoomScale = 2.0f;
        pageScrollView.zoomScale = 1.0f;
        pageScrollView.backgroundColor=[UIColor clearColor];
        pageScrollView.delegate = self;
        [pageScrollView addSubview:self.imageview];
        [mainScrollView addSubview:pageScrollView];
        [self.pageScrollViewObjArray addObject:pageScrollView];

And whenever i need to access a particular imageview contained inside scrollview i do this :-

UIScrollView *sv=(UIScrollView*)[self.pageScrollViewObjArray objectAtIndex:swipeCounter];
sv.zoomScale=1.0f;

But as i said earlier i don’t know how efficient this code is,but its been more than a month the app is on store and being tested properly ,yet no issue because of this.