[DefaultValue(null)]
[Parameter]
public string CheckedDisplayText { get; set; }

@inject ProductService ProductData

<DxGrid Data="@products">
    <Columns>
        <DxGridDataColumn FieldName="ProductName" />
        <DxGridDataColumn FieldName="UnitPrice" />
        <DxGridDataColumn FieldName="UnitsInOrder" />
        <DxGridDataColumn FieldName="Discontinued">
            <EditSettings>
                <DxCheckBoxSettings ShowCheckBoxInDisplayMode="false"
                                    CheckedDisplayText="Yes"
                                    IndeterminateDisplayText="Unknown"
                                    UncheckedDisplayText="No" />
            </EditSettings>
        </DxGridDataColumn>
    </Columns>
</DxGrid>

@code {
    private Product[]? products;
    protected override async Task OnInitializedAsync() {
        products = await ProductData.GetData();
    }
}

public enum State { Yes, No, Unknown }

public class Product {
    public int ProductID { get; set; }
    public string ProductName { get; set; }
    public decimal? UnitPrice { get; set; }
    public short? UnitsInOrder { get; set; }
    public bool? Discontinued { get; set; }
}

public class ProductService {
    public Task<Product[]> GetData() {
        List<Product> products = new List<Product>();
        products.Add(new Product() { ProductID = 1, ProductName = "Chai", UnitPrice = 19, UnitsInOrder = 20, Discontinued = true });
        products.Add(new Product() { ProductID = 2, ProductName = "Chang", UnitPrice = 19, UnitsInOrder = 40, Discontinued = true });
        products.Add(new Product() { ProductID = 3, ProductName = "Aniseed Syrup", UnitPrice = 10, UnitsInOrder = 70, Discontinued = true });
        products.Add(new Product() { ProductID = 4, ProductName = "Mishi Kobe Niku", UnitPrice = 97, UnitsInOrder = 32, Discontinued = false });
        products.Add(new Product() { ProductID = 5, ProductName = "Ikura", UnitPrice = 31, UnitsInOrder = 10 });
        products.Add(new Product() { ProductID = 6, ProductName = "Chef Anton's Cajun Seasoning", UnitPrice = 22, UnitsInOrder = 12, Discontinued = false });
        products.Add(new Product() { ProductID = 7, ProductName = "Chef Anton's Gumbo Mix", UnitPrice = 21.35m, UnitsInOrder = 16, Discontinued = true });
        products.Add(new Product() { ProductID = 8, ProductName = "Grandma's Boysenberry Spread", UnitPrice = 25, UnitsInOrder = 20, Discontinued = true });
        products.Add(new Product() { ProductID = 9, ProductName = "Uncle Bob's Organic Dried Pears", UnitPrice = 30, UnitsInOrder = 24, Discontinued = false });
        products.Add(new Product() { ProductID = 10, ProductName = "Northwoods Cranberry Sauce", UnitPrice = 40, UnitsInOrder = 18, Discontinued = false });
        products.Add(new Product() { ProductID = 11, ProductName = "Queso Cabrales", UnitPrice = 21, UnitsInOrder = 30 });
        products.Add(new Product() { ProductID = 12, ProductName = "Queso Manchego La Pastora", UnitPrice = 38, UnitsInOrder = 10 });
        return Task.FromResult(products.ToArray());
    }
}