ios - How do I nest blocks so they end at the same time -

how turn method block won't complete until 'request startwithcompletionhandler' block completes it's request , code in own block?

i have series of blocks need call in order require code sent requests. trying find clean way accomplish task.

+(void)???????? ^block() {     fbrequest *request = [fbrequest requestforgraphpath:kfacebookquerymekey];     [request startwithcompletionhandler:^(fbrequestconnection *connection, id result, nserror *error) {         ....     }]; } 

added info: yes, want outer function wait until inner function complete

thanks.

it depends on mean. given example code, seems want function call block when nested block completes. you'd want this:

+ (void)domythingwithblock:(void(^)(void))block {     fbrequest *request = [fbrequest requestforgraphpath:kfacebookquerymekey];     [request startwithcompletionhandler:^(fbrequestconnection *connection, id result, nserror *error) {          // whatever want connection ...          if (block) block();      }]; } 

on other hand, maybe want outer function wait nested block complete before returns. in case, it's bit more complicated. need use lock wait block complete, this:

#define kmythingnotdone 0 #define kmythingdone    1  + (void)domythingandwait {     nsconditionlock *lock = [[nsconditionlock alloc] initwithcondition:kmythingnotdone];      fbrequest *request = [fbrequest requestforgraphpath:kfacebookquerymekey];     [request startwithcompletionhandler:^(fbrequestconnection *connection, id result, nserror *error) {          // whatever want connection ...          [lock lock];         [lock unlockwithcondition:kmythingdone];      }];      [lock lockwhencondition:kmythingdone];     [lock unlock]; } 

be warned - don't want on main thread, or you'll lock user interface. have sure request isn't going wait happen on thread call from, otherwise you'll end deadlock.