ios - ALAssetsLibrary resultBlock weak or strong reference -


for call

[library assetforurl:referenceurl resultblock:^(alasset *asset){...}

if pass image imageview, should pass imageview weak reference or should strong reference? can ever go wrong passing weak reference? weak reference mean

__weak myvc *weakself = self;  .... weakself.myimageview...

block retains object reference , in turn create retain cycle. in above code snippet, block creates retain cycle, need use weak reference break retain cycle as

 __weak typeof(self) *weakself = self;

or can implement in following way

__block myvc *blockself = self;

and reference blockself inside block.

this avoids cycle, because blockself not retained


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