 
             // MARK: More Message Types
 
-            self.choosePhotoButton.title = NSLocalizedString("Choose photo", comment: "")
-            self.choosePhotoButton.tapAction = { [weak self] in
+            choosePhotoButton.title = NSLocalizedString("Choose photo", comment: "")
+            choosePhotoButton.tapAction = { [weak self] in
 
                 let openCameraRoll: ProposerAction = { [weak self] in
                     if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.PhotoLibrary){


        // 尽量晚的设置一些属性和闭包

        dispatch_once(&lazyOnceToken) { [unowned self] in

            // MARK: Notify Typing

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

            self.messageToolbar.notifyTypingAction = {

                if let withFriend = self.conversation.withFriend {



            // MARK: MessageToolbar State Transitions

            messageToolbar.stateTransitionAction = { [weak self] (messageToolbar, previousState, currentState) in

                if let strongSelf = self {

