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iosobjective-cxcodeicarousel

How to fade all items before currentItem with iCarousel?


I'm using iCarousel plugin with custom transformations and I try to make a specific fade effect. I want all items before current item faded but current item and all after not faded. Is there a way to do this with fade options ? I tried but didn't succeed. So I tried to make animations on views of the carousel. This is what i got here :

- (void)carouselCurrentItemIndexDidChange:(iCarousel *)carousel
{
    UIView *viewToFadeOut = [carousel itemViewAtIndex:self.carousel.currentItemIndex-1];
    [UIView animateWithDuration:0.5 delay:0.0 options:0 animations:^{
        viewToFadeOut.alpha = 0.6f;
    } completion:^(BOOL finished) {

    }];

    UIView *viewToFadeIn = [carousel itemViewAtIndex:self.carousel.currentItemIndex];
    [UIView animateWithDuration:0.5 delay:0.0 options:0 animations:^{
        viewToFadeIn.alpha = 1.0f;
    } completion:^(BOOL finished) {

    }];
}

But it doesn't work exactly as I want because the fadeIn animation starts once the current item changed and so animation starts too late.

Maybe is there a way to implement a method like

- (void)carouselCurrentItemIndexWillChange:(iCarousel *)carousel;

and start the fadeOut animation with a delay ?


Solution

  • If I've understood correctly, you simply need to add this to your delegate:

    - (CGFloat)carousel:(iCarousel *)carousel valueForOption:(iCarouselOption)option withDefault:(CGFloat)value
    {
        if (option == iCarouselOptionFadeMin)
        {
            return 0.0;
        }
        else if (option == iCarouselOptionFadeMinAlpha)
        {
            return 0.6;
        }
        return value;
    }