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POiCarousel viewForItemAtIndex using custom UIView resuses first images loaded
 

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    <p>I have no trouble using iCarousel with UIImageViews, everything works great.</p> <p>However, I wanted to add some extra drawing with the image, so I did a quick subclass of UIView that included an image and had a custom draw routine. Simple enough. However, inside of the <strong><em>viewForItemAtIndex</em></strong>, when I set the image property, it doesn't update visually. Instead it repeats the n images that represented the visible images and thus the originally loaded objects.</p> <p>Example, I have 26 images, a - z. 5 visible on startup, a - e. Without the 'setNeedsReload' i get images a - e repeatedly, instead of a - z, when I scroll through the view.</p> <p>I have found that if I add '<strong><em>setNeedsDisplay</em></strong>' inside the setImage property, it will work correctly. However, there is a huge performance penalty.</p> <p>My question is two fold:</p> <ol> <li>Am I missing something?</li> <li>Should I just extend UIImageView instead and do the custom drawing inside a 'processImage' style method like Nick did in FXImage?</li> </ol> <p>Thanks,</p> <pre><code>/// GroupImageView.m - (void)setImage:(UIImage *)newImage { image = newImage; [self setNeedsDisplay]; } // override of the drawRect routine. - (void)drawRect:(CGRect)rect { // only draw if we have an image to draw if (image) { CGContextRef context = UIGraphicsGetCurrentContext(); // blah blah, fancy drawing crap CGContextRotateCTM (context, radians((rand() % 5 + 2))); CGContextTranslateCTM(context, -0.5f * insetRect.size.width, -0.5f * insetRect.size.height); CGContextFillRect(context,insetRect); // etc [image drawInRect:insetRect blendMode:kCGBlendModeNormal alpha:[self alpha]]; // etc } } </code></pre> <hr> <pre><code>- (UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view { if (view == nil) { view = [[GroupImageView alloc] initWithImage:[UIImage imageNamed:@"Loading.png"]]; } CGImageRef ref = [group posterImage]; UIImage* coverImage; if (ref) { coverImage = [UIImage imageWithCGImage:ref scale:1/scaleFactor orientation:UIImageOrientationUp]; } else { coverImage = [UIImage imageNamed:@"Sunflower.png"]; } [(GroupImageView*)view setImage:coverImage]; return view; } </code></pre>
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