public void LoadMessage(string messageId)
        {
            if (fetchMessageRequest != null)
            {
                fetchMessageRequest.Cancel();
            }

            message = null;
            StartLoading(messageId);
        }
        void Inbox.IFetchMessagesCallback.OnFinished(bool success)
        {
            message = MessageCenterClass.Shared().Inbox.GetMessage(messageId);
            if (!success)
            {
                messagePage.OnRendererLoadFailed(messageId, true, MessageFailureStatus.FetchFailed);
                return;
            }
            else if (message == null || message.IsExpired)
            {
                messagePage.OnRendererLoadFailed(messageId, false, MessageFailureStatus.Unavailable);
                return;
            }

            webView.LoadMessage(message);
            messagePage.OnRendererLoadStarted(messageId);
        }
        private void StartLoading(string messageId)
        {
            this.message = MessageCenterClass.Shared().Inbox.GetMessage(messageId);
            if (message == null)
            {
                fetchMessageRequest = MessageCenterClass.Shared().Inbox.FetchMessages(this);
            }
            else
            {
                if (message.IsExpired)
                {
                    messagePage.OnRendererLoadFailed(messageId, false, MessageFailureStatus.Unavailable);
                    return;
                }

                webView.LoadMessage(message);
                messagePage.OnRendererLoadStarted(messageId);
            }
        }