objective-c - 垃圾收集器和核心基础

Question

我编写了一个将图像加载到 CALayer 的方法。这是代码:

- (CGImageRef)loadImage:(NSString*)path {
          // Get data image
          CGImageRef image = NULL;
          NSData *data = [NSData dataWithContentsOfFile:path];
          CFDataRef imgData = (CFDataRef)data;
          CGDataProviderRef imgDataProvider = CGDataProviderCreateWithCFData (imgData);

          // Get CGImage from CFDataRef
          image = CGImageCreateWithJPEGDataProvider(imgDataProvider, NULL, true, kCGRenderingIntentDefault);

          // If the image isn't a JPG Image, would be PNG file
          if (!image)
               image = CGImageCreateWithPNGDataProvider(imgDataProvider, NULL, true, kCGRenderingIntentDefault);

          return image;
}

我在 CALayer 中使用此方法:

NSString *pathString = // my image path;
aLayer = [CALayer layer];
aLayer.contents = [self loadImage:pathString];

工作了。我最终确定了我的观点(使用垃圾收集器)，但我的应用程序存在泄漏。我应该释放 CFDataRef imgData 吗？我读到垃圾收集器在 Core Foundation 中不起作用。
谢谢，请原谅我的英语。

Answer 1

您负责通过调用 CGImageRelease 来释放该对象。

请参阅有关垃圾收集的文档:

http://developer.apple.com/library/mac/#documentation/cocoa/Conceptual/GarbageCollection/Articles/gcCoreFoundation.html

By default, therefore, in a garbage-collected environment you manage Core Foundation objects exactly as you would in a reference-counted environment (as described in Memory Management Programming Guide for Core Foundation > “Ownership Policy”). If you create or copy a Core Foundation object, you must subsequently release it when you’re finished with it. If you want to keep hold of a Core Foundation object, you must retain it and again subsequently release it when you’re finished with it.