ios - Retain Cycles for Blocks Inside of Blocks -

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do have continuously declare weak references break retain cycles blocks inside of blocks?

__weak typeof(self) weakself = self; [self setmyblock:^(id obj, nsuinteger idx, bool *stop) {     typeof(self) strongself = weakself;     [strongself dosomething];     [strongself setmyblock:^(id obj, nsuinteger idx, bool *stop) {         //do need create weak reference strongself block?         [strongself dosomething];     }];   }];

i'm afraid so. [strongself setmyblock:<inner block>] cause self retain inner block. if inner block has strong reference self, that's cycle. fact strongself variable assigned from __weak qualified variable not make difference.

as other users mentioned, can use original weakself rather creating new one. reason create strongself reference in block otherwise self might deallocated while block running. strongself either end nil (if self deallocated before strongself assigned, causes no harm) or else self not deallocated while block executing, because have strong reference. during time have strong reference self, original weakself also safe use, because self not deallocated.


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