public void TestCommand()
        {
            var vm = new LayoutFieldViewModel();
            var layoutViewModel = Mock.Create<LayoutViewModel>();
            layoutViewModel.LayoutList = new ObservableCollection<LayoutFieldViewModel>() { new LayoutFieldViewModel() { ColumnName = "ColName", ColumnSystemName = "ColumnSystemName" } };

            vm.Initialize(string.Empty, string.Empty, layoutViewModel);

            Assert.IsNotNull(vm.ReturnColumnCommand);
        }