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POIs there a reason I can't initialize a CALayer outside a UIView class?
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  1. POIs there a reason I can't initialize a CALayer outside a UIView class?
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    copied!<p>I have been trying to us CALayers as "sprites" in an iPhone application I'm working on. From what I have been reading, that seems like the correct thing to do here.</p> <p>When I setup the layer inside a UIView class I am able to get the layer to show up on the screen: NSLog(@"GameView initWithCoder");</p> <pre><code>NSString* imagePath = [[NSBundle mainBundle] pathForResource:@"earth" ofType:@"png"]; earthImage = [[UIImage alloc] initWithContentsOfFile:imagePath]; earthLayer = [CALayer layer]; [earthLayer setContents:(id)[earthImage CGImage]]; [earthLayer setBounds:CGRectMake(0, 0, 32, 32)]; [earthLayer setPosition:CGPointMake(50, 50)]; [earthLayer setName:@"earth"]; [[self layer] addSublayer:earthLayer]; </code></pre> <p>However, when I attempt to initialize the CALayer outside the UIView, my application crashes:</p> <pre><code>- (void)loadImage:(NSString*)fileName { NSLog(@"GamePiece loadImage"); NSArray* fileNameParts = [fileName componentsSeparatedByString:@"."]; imageName = [[fileNameParts objectAtIndex:0] retain]; NSString* ext = [fileNameParts objectAtIndex:1]; NSString* imagePath = [[NSBundle mainBundle] pathForResource:imageName ofType:ext]; image = [[UIImage alloc] initWithContentsOfFile:imagePath]; layer = [CALayer layer]; [layer setContents:(id)[image CGImage]]; [layer setBounds:CGRectMake(0.0f, 0.0f, 32.0f, 32.0f)]; [layer setPosition:CGPointMake(50.0f, 50.0f)]; [layer setName:imageName]; [fileNameParts release], fileNameParts = nil; [ext release], ext = nil; } </code></pre> <hr> <pre><code>NSLog(@"GameView initWithCoder"); earth = [[GamePiece alloc] init]; [earth loadImage:@"earth.png"]; [[self layer] addSublayer:[earth layer]]; </code></pre> <p>Clearly I'm doing something wrong here, but I just don't know what that would be. I have read the Core Animation Programming Guide and also the iPhone Application Programming Guide, but they really don't seem to talk about how to initialize a CALayer other than in passing.</p> <p>I just need a gentle nudge in the correct direction. I have been getting a pretty good understanding about everything else I have learned when it comes to programming the iPhone. I'm just having some issues with Graphics, Layers and Animation.</p> <p>Thanks in advance!</p>
 

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