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    <p>Don't use <code>-drawLayer:inContext:</code>. That method is for drawing into a CG context which will then become the layer's contents, using Core Graphics or UIKit methods. You don't want to change the layer's contents at all -- you want to set it to be your image, once, and then never touch it again.</p> <p>Your image is appearing and disappearing, because sometimes the layer displays the image, and other times the layer displays what you drew into the context in <code>-drawLayer:inContext:</code> -- namely, nothing.</p> <p>(Also: in order for <code>-drawLayer:inContext:</code> to be called, you must be calling <code>[layer setNeedsDisplay]</code>, or you have the layer's <code>needsDisplayOnBoundsChange</code> turned on, or something similar. Don't do any of that.)</p> <p>Instead, try using the <code>CALayer</code> layout machinery. For instance, in your layer's delegate:</p> <pre><code>- (void)layoutSublayersOfLayer:(CALayer *)layer { float alpha = layer.position.y / layer.superlayer.bounds.size.height; UIColor *reddish = [UIColor colorWithRed:1.0 green:0.0 blue:0.0 alpha:alpha]; CGColorRef cgReddish = reddish.CGColor; layer.backgroundColor = cgReddish; } </code></pre> <p>This will get called as part of the display process, anytime the layer or any of its superlayers have had their <code>-setNeedsLayout</code> method called. Often this happens automatically, but depending on exactly what causes the layer to move, you may need to do it manually. Try it and see.</p> <p>(Alternatively: Since you already have code that changes the layer's position, why not change the layer's background color at the same time?)</p>
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    1. POUIImage content disappearing (and reappearing) when using drawLayer:inContext
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    1. COThat definitely makes more sense. What if I only wanted to change the opacity of the content image but leave the background color the same? (I am calling setNeedsDisplay on this layer.)
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    2. COYou might need two layers, one to draw the background, another the image. You'd vary the `opacity` property of the image layer. Depending on your setup, one of the layers could be a sublayer of the other -- it might make it easier to organize that way.
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    3. COThat's exactly what I did. 2 layers with the image layer as a sublayer of the other then just varying the opacity of the image layer. Works great now! Thanks!
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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