UIScrollVIew View

Question

I'm using iCarousel as a slot machine, for those who doesn't know iCarousel it is a UIScrollview with (paged, scrolling views). So in my app, I scroll it, then when it stops it shows the Image(Result) for 3 seconds, then a button pop-ups, if you press the button, it will delete the View(Image Result) then Rotates again.

Here is my way of deleting my carousel view:

    NSInteger CurrentImage = carousel.currentItemIndex;
    [carousel removeItemAtIndex:CurrentImage animated:YES];
    [images removeObjectAtIndex:CurrentImage];

But then when the carousel.numberOfItems has 1 item left, it doesnt scroll, instead its just stuck there.

So I made a way to make it scroll even it has only 1 Item(index) left.

I inserted it with the last index, so I tried this:

[self.carousel insertItemAtIndex:0 animated:NO];

(but doesnt work)

then I tried another:

int lastObject = [images objectAtIndex: ([images count]-1)]
[self.carousel insertItemAtIndex:lastObject animated:NO];

(still doesnt work)

and also this:

int count = [images count];
[images objectAtIndex:count - 1];

(still no luck)

Am I doing wrong? or What are other ways? Or can I just duplicate the last View? Thanks for the help.

EDIT: Methods

     - (NSUInteger)numberOfItemsInCarousel:(iCarousel *)carousel
    {
        if ([images count] == 1 || [self.carousel numberOfItems] == 1)
            return 2;

        return [images count];
    }

    - (NSUInteger)numberOfVisibleItemsInCarousel:(iCarousel *)carousel
    {
        //limit the number of items views loaded concurrently (for performance reasons)
        return 7;
    }


    - (UIView *)carousel:(iCarousel *)_carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view
    {

        if (index >= [images count] || index >= [carousel numberOfItems]) {
            index = 0;
        }

        NSDictionary *obj = [images objectAtIndex:index];
        view = [[UIImageView alloc] initWithImage:[obj objectForKey:@"image"]];
        view.tag = index;

        return view;
    }


    - (NSUInteger)numberOfPlaceholdersInCarousel:(iCarousel *)carousel
    {
        //note: placeholder views are only displayed on some carousels if wrapping is disabled
        return 0;
    }


    - (CGFloat)carouselItemWidth:(iCarousel *)carousel
    {
        //usually this should be slightly wider than the item views
        return 400;
    }

 - (BOOL)carousel:(iCarousel *)carousel shouldSelectItemAtIndex:(NSInteger)index{
    return 5;  
}   
    - (BOOL)carouselShouldWrap:(iCarousel *)carousel
    {
        //wrap all carousels
        return wrap;
    }

Delete Method:

-(void) deleteItem{
    //Removes the object chosen 
    if (carousel.numberOfItems >= 1)
    {   
        NSInteger index = carousel.currentItemIndex;
        [carousel removeItemAtIndex:index animated:YES];
        //[images removeObjectAtIndex:index];
        //[images replaceObjectAtIndex:index withObject:[NSNull null]];
    } 

}

I'm sorry I dont understand, you want to rotate an object with only one element in it? — Spire, Jul 05 '12 at 07:48
hmmmm, something like that. or make the 1 element a duplicate then rotate it. — Bazinga, Jul 05 '12 at 07:57
try if-else statement and when you have 1 element insert it twice, then you will have 2 elements and can rotate them. Just an idea — Spire, Jul 05 '12 at 08:06
`if([images count]==1){ [self.carousel insertItemAtIndex:0 animated:NO]; [self.carousel insertItemAtIndex:1 animated:NO]; }else{ }` it's just a guideline — Spire, Jul 05 '12 at 13:32

sergio · Accepted Answer · 2012-07-05T10:57:22.083

1

What you could do is make

- (NSUInteger)numberOfItemsInCarousel:(iCarousel*)carousel;

return always a value >1 (eg. 2); then make sure that

- (UIView*)carousel:(iCarousel*)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView*)view;

always returns a correct view for the minimum number of elements you return from numberOfItemsInCarousel.

Eg.

- (NSUInteger)numberOfItemsInCarousel:(iCarousel*)carousel {
   if (numberOfViews == 1)
      return 2;
   return numberOfViews;
}


- (UIView*)carousel:(iCarousel*)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView*)view {

  if (index >= numberOfViews) {
      index = 0;
  }

  NSDictionary *obj = [images objectAtIndex:index];
  view = [[UIImageView alloc] initWithImage:[obj objectForKey:@"image"]];
  view.tag = index;
  return view;
}

You should also make sure that the last element is never deleted of add some guards in the code above to manage the case when no elements are left.

edited Jul 05 '12 at 10:57

answered Jul 05 '12 at 09:03

sergio

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well, I tried and it works; you will have some other issue preventing that from working. in any case, I modified a little bit the code so to make its integration with your code easier. – sergio Jul 05 '12 at 10:37
Ill post my code here like your code, can you kindly check it sir? – Bazinga Jul 05 '12 at 10:40
I'm really having problem with this part `numberOfViews`. I dunno if Im doing it right, if it should be `[images count]` or `carousel.numberOfItems`. please help sir. :( – Bazinga Jul 06 '12 at 02:31
I think that `[images count]` is ok. To move on, you should set a breakpoint in `numberOfItemsInCarousel` and `viewForItemAtIndex` and look at why they do not work as expected... maybe you have one image left in the carousel but `images` contains more elements, or I don't know what... – sergio Jul 06 '12 at 07:20
I was able to make it work, but it works only when view i loaded with 1 image, but when removing it doesn't, what can I do? – Bazinga Jul 06 '12 at 10:01
what do you mean: when removing it doesn't? if you remove the last image, what do you expect to see? – sergio Jul 06 '12 at 10:33
for example:when view LOADS(newly loaded) I have two images present, then I delete the result image then only 1 remains, it doesn't rotate. BUT,when view LOADS(newly loaded) then I only have 1 image present in my array, it rotates. – Bazinga Jul 06 '12 at 10:35
I have to admit that I have a pretty fuzzy view now... maybe you could post your full code for the delegate methods and how you deal with image deletion... – sergio Jul 06 '12 at 17:09
Your code seems ok. Could you try calling `loadUnloadViews` or `reloadData` after deleting a view when `carousel.numberOfItems == 1`? (or each time you delete). this could make it work, I hope... – sergio Jul 07 '12 at 20:14
the `loadUnloadView` can't be called on mine. only `reloadData` but, when reloadData is called, the last deleted item item is redisplay on the view. :( – Bazinga Jul 09 '12 at 02:15
Then it seems, that you did not update your data source. I think the only chance you have to fix this is by debugging into those methods and see what happens in actuality. Sorry I can't help further... – sergio Jul 09 '12 at 09:00
Thank you for the help. here is one of my bounty question, if you want to just take a look. http://stackoverflow.com/questions/11200584/nsmutablearray-difficulty – Bazinga Jul 09 '12 at 09:01

UIScrollVIew View

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