ios - UIAlertView for when fetching JSON fails -

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• fetching json data after failed retrieval 1 answer

i'm trying uialertview run when fetching json data fails, can't seem work. i'd appreciate if show me how or point me in right direction!

i think have forget write failure block.

afhttprequestoperation *operation = [[afhttprequestoperation alloc]initwithrequest:request]; [operation  setcompletionblockwithsuccess:^(afhttprequestoperation *operation, id responseobject) {     nslog(@"success: %@", operation.responsestring); }      failure:^(afhttprequestoperation *operation, nserror *error) {         nslog(@"error: %@",  operation.responsestring); }]; 

hope you.