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POLoading new images into UIImageView, memory from previous images is not released
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copied!<p>My app has a view with three <code>UIImageViews</code>. There are about 150 images as resource files, each a .jpg of about 24k. The app will show all of the images, but only three at a time.</p> <p>But every time I click the button to load three more images into the <code>UIImageViews</code>, the "Overall Bytes" column in Instruments increases by about 700K, until I eventually get a low memory warning and then the app crashes. Somehow, the memory I use for each load of three images isn't being released.</p> <p>I've googled around and tried every way I know to do this, but no success and I need help.</p> <p>I've tried this: (This code is part of the action to load three more images. The three ImageViews are <code>imgShownLeft</code>, <code>imgShownMiddle</code>, and <code>imgShownRight</code>. Those are instance variables. I first have to put <code>currentImage</code> in all three <code>UIImageViews</code>, and then put <code>previousImage</code> in the left one and <code>nextImage</code> in the right one:</p> <pre><code>NSString *strImageToSet = [[imgNamesArray objectAtIndex:currentImage] stringByAppendingFormat:@".jpg"]; UIImage *img = [UIImage imageNamed:strImageToSet]; [imgShownMiddle setImage:img]; [imgShownLeft setImage:img]; [imgShownRight setImage:img]; NSString *strPreviousImage = [[imgNamesArray objectAtIndex:previousImage] stringByAppendingFormat:@".jpg"]; img = [UIImage imageNamed:strPreviousImage]; [imgShownLeft setImage:img]; NSString *strNextImage = [[imgNamesArray objectAtIndex:nextImage] stringByAppendingFormat:@".jpg"]; img = [UIImage imageNamed:strNextImage]; [imgShownRight setImage:img]; </code></pre> <p>Then I tried this: instead of:</p> <pre><code> UIImage *img = [UIImage imageNamed:strImageToSet]; </code></pre> <p>I used:</p> <pre><code> UIImage *img = [[UIImage alloc] initWithContentsOfFile:strImageToSet]; </code></pre> <p>and assigned <code>img</code> to the <code>UIImageViews</code> the same way, followed by <code>[img release];</code></p> <p>Then I tried:</p> <pre><code> UIImage *img = [[[UIImage alloc] initWithContentsOfFile:strImageToSet] autorelease]; </code></pre> <p>Then I tried:</p> <pre><code> img = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[imgNamesArray objectAtIndex:currentImage] ofType:@"jpg"]]; </code></pre> <p>But in every case the memory requirements grew with each run of this action.</p> <p>I know it's possible to keep three images loaded at a time without holding 150 images in memory! What am I doing wrong?</p> <p>Thanks for any insight. /SD</p>

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