private void NewExecute(object obj)
        {
            var temp = new SimpleModel();

            SideBar.AddItem(temp);
            SideBar.SelectedItem = temp;
            SelectedNodeModel    = new NodeModel();
            SelectedGraph        = GraphModels.FirstOrDefault();
            SaveCommand.NotifyCanExecuteChanged();
        }
        private async void SelectExecute(SimpleModel obj)
        {
            if (obj != null && obj.Id != 0)
            {
                var result = await _nodeService.GetByIdAsync(obj.Id);

                if (result.Succeed)
                {
                    SelectedNodeModel = result.Value;
                    SelectedGraph     = GraphModels.FirstOrDefault(x => x.Id == SelectedNodeModel.GraphId);
                }
                else
                {
                    await ShowMessage(result.ErrorMessage);
                }
            }

            SaveCommand.NotifyCanExecuteChanged();
        }