ios - Mixing Blocks and Delegates in Objective-C -

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this question has answer here:

is possible run block when delegate receives message?

for example, if had framework took void block parameter (we'll call "success" block), , using nsurlconnection delegate stuff method arguments, when receive response webpage, how can call "success" block passed in method parameters?

this really hard me explain, , don't have code this, can clarify if have questions.

you absolutely can. how all completion handlers / callbacks work. in fact, block for.

to take simple example, consider nsurlconnection class method:

+ (void)sendasynchronousrequest:(nsurlrequest *)request                           queue:(nsoperationqueue *)queue               completionhandler:(void (^)(nsurlresponse *response,                                           nsdata *data,                                           nserror *connectionerror))handler

for third parameter, pass block. , when request over, time in future, nsurlconnection do? calls block.

so, can same nsurlconnection doing. can write method takes block, hold on block, perhaps takes time, , later call block.


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