public HistoryMessageViewModel(MainViewModel viewModel)
        {
            _viewModel = viewModel;
            HistoryMessages = _viewModel.HistoryMessages;

            Title = "历史消息列表";
        }
        public HistoryMessageWindow(MainViewModel viewModel)
        {
            InitializeComponent();

            _viewModel = new HistoryMessageViewModel(viewModel);

            this.DataContext = _viewModel;
        }