ios - wait until scrollToRowAtIndexPath is done in swift -

i have uitableview more cells fit on screen. when notification data model want jump specific row , show basic animation.

my code is:

 func animatebackgroundcolor(indexpath: nsindexpath) {             dispatch_async(dispatch_get_main_queue()) {         nslog("table should @ right position")         if let cell = self.tableview.cellforrowatindexpath(indexpath) as? basiccardcell {             var actcolor = cell.backgroundcolor             self.manager.vibrate()             uiview.animatewithduration(0.2, animations: { cell.backgroundcolor = uicolor.redcolor() }, completion: {                 _ in                  uiview.animatewithduration(0.2, animations: { cell.backgroundcolor = actcolor }, completion: { _ in                         self.readnotificationcount--                         if self.readnotificationcount >= 0 {                             var legiccard = self.legiccards[indexpath.section]                             legiccard.wasread = false                             self.reloadtableviewdata()                         } else {                             self.animatebackgroundcolor(indexpath)                         }                 })             })         }     } }      func cardwasread(notification: nsnotification) {     readnotificationcount++     nslog("\(readnotificationcount)")          if let userinfo = notification.userinfo as? [string : anyobject], let index = userinfo["index"] as? int {              dispatch_sync(dispatch_get_main_queue()){                 self.tableview.scrolltorowatindexpath(nsindexpath(forrow: 0, insection: index), atscrollposition: .none, animated: true)                  self.tableview.layoutifneeded()                 nslog("table should scroll selected row")             }             self.animatebackgroundcolor(nsindexpath(forrow: 0, insection: index))         } } 

i hoped dispatch_sync part delay execution of animatebackgroundcolor method until scrolling done. unfortunately not case animatebackgroundcolor gets called when row not visible yet -> cellforrowatindexpath returns nil , animation won't happen. if no scrolling needed animation works without problem.

can tell how delay execution of animatebackgroundcolor function until scrolling done?

thank , kind regards

delaying animation not seem solution since scrolltorowatindexpath animation duration set based on distance current list item specified item. solve need execute animatebackgroudcolor after scrolltorowatindexpath animation completed implementing scrollviewdidendscrollinganimation uitableviewdelegate method. tricky part here indexpath @ tableview did scroll. possible workaround:

var indexpath:nsindexpath?  func cardwasread(notification: nsnotification) { readnotificationcount++ nslog("\(readnotificationcount)")      if let userinfo = notification.userinfo as? [string : anyobject], let index = userinfo["index"] as? int{          dispatch_sync(dispatch_get_main_queue()){              self.indexpath = nsindexpath(forrow: 0, insection: index)             self.tableview.scrolltorowatindexpath(self.indexpath, atscrollposition: .none, animated: true)              self.tableview.layoutifneeded()              nslog("table should scroll selected row")         }      }  }  func scrollviewdidendscrollinganimation(scrollview: uiscrollview) {     self.animatebackgroundcolor(self.indexpath)     indexpath = nil }