objective c - Returning method object from inside block -

objective c - Returning method object from inside block -

i wondering how next correctly: have method homecoming nsdata object. gets nsdata object uidocument. nsdata object can large, want create sure loaded before response starts. hence homecoming value of method within block itself. this:

- (nsdata*)getmydata { myuidocument *doc = [[myuidocument alloc] initwithfileurl:fileurl]; [doc openwithcompletionhandler:^(bool success) { if (success) { homecoming doc.myresponsedata; // homecoming method not block } }]; }

this causes error because return apparently refers block's return.

how can accomplish without having create thread blocking wait/while loop?

thanks.

you can't. encompass fact you're trying asynchronous , add together completion block parameter getmydata method called when inner completion handler called. (and remove return method signature):

- (void)getmydatawithcompletion:(void(^)(nsdata *data))completion { myuidocument *doc = [[myuidocument alloc] initwithfileurl:fileurl]; [doc openwithcompletionhandler:^(bool success) { completion((success ? doc.myresponsedata : nil)); }]; }

objective-c ios7 block uidocument completionhandler