31 lines
645 B
31 lines
645 B
5 years ago
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A retain cycle is a situation when object A retains object B, and object B
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retains object A at the same time. Here is an example:
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```objectivec
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@class Child;
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@interface Parent : NSObject {
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Child *child; // Instance variables are implicitly __strong
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}
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@end
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@interface Child : NSObject {
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Parent *parent;
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}
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@end
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```
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You can fix a retain cycle in ARC by using \_\_weak variables or weak properties
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for your "back links", i.e. links to direct or indirect parents in an object
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hierarchy:
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```objectivec
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@class Child;
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@interface Parent : NSObject {
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Child *child;
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}
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@end
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@interface Child : NSObject {
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__weak Parent *parent;
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}
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@end
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```
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