                 })
             }
 
-            self.addLocationButton.title = NSLocalizedString("Share location", comment: "")
-            self.addLocationButton.tapAction = {
-                self.performSegueWithIdentifier("presentPickLocation", sender: nil)
+            addLocationButton.title = NSLocalizedString("Share location", comment: "")
+            addLocationButton.tapAction = { [weak self] in
+                self?.performSegueWithIdentifier("presentPickLocation", sender: nil)
             }
         }
     }

                }
            }
            
            self.messageToolbar.voiceRecordEndAction = { [weak self] messageToolbar in

                YepAudioService.sharedManager.shouldIgnoreStart = true
                


        // 尽量晚的设置一些属性和闭包

        if isFirstAppear {

            isFirstAppear = false

            // MARK: Notify Typing

            checkTypingStatusTimer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("checkTypingStatus"), userInfo: nil, repeats: true)

            messageToolbar.notifyTypingAction = {

                if let withFriend = self.conversation.withFriend {

