public void Modify(FilterItem item)
        {
            CustomFilterViewModel viewModel = CreateCustomFilterViewModel <CustomFilterViewModel>(item);

            if (ShowFilterDialog(viewModel, "Custom Filter"))
            {
                if (viewModel.Save)
                {
                    ModifyCustomFilter(item);
                    RaiseFilterTreeChanged();
                }
                ApplyFilter(item);
            }
        }
        public void New()
        {
            var newFilterItem = CreateFilterItem(null, null);
            CustomFilterViewModel viewModel = CreateCustomFilterViewModel <CustomFilterViewModel>(newFilterItem);

            if (ShowFilterDialog(viewModel, "Custom Filter"))
            {
                if (viewModel.Save)
                {
                    AddNewCustomFilter(newFilterItem);
                    RaiseFilterTreeChanged();
                }
                SelectedItem = newFilterItem;
            }
        }