GridAllowedDropTarget Enum

Lists values that specify allowed drag-and-drop targets.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public enum GridAllowedDropTarget

Members

Name	Description
None	Users cannot reorder rows or drop them onto this Grid from another component.
Internal	Users can reorder rows within this Grid.
External	Users can drop rows onto other components.
All	Users can reorder rows within this Grid and drop them onto other components.

Related API Members

The following properties accept/return GridAllowedDropTarget values:

Library	Related API Members
Blazor	DxGrid.AllowedDropTarget
	IGrid.AllowedDropTarget
XAF: Cross-Platform .NET App UI & Web API	DxGridModel.AllowedDropTarget

Remarks

In the following example, the first Grid allows users to drag rows to external targets. The second Grid accepts rows from the first Grid and allows row reordering:

Run Demo: Drag and Drop Rows - Between Components

<DxGrid @ref="@InStockGrid"
        Data="InStockProducts"
        AllowDragRows="true"
        AllowedDropTarget="GridAllowedDropTarget.External">
    <Columns>
        <DxGridDataColumn FieldName="ProductName" MinWidth="50" />
        <DxGridDataColumn FieldName="UnitPrice" DisplayFormat="c2" />
    </Columns>
</DxGrid>

<DxGrid Data="DiscontinuedProducts"
        AllowDragRows="true"
        AllowedDropTarget="GridAllowedDropTarget.All"
        ItemsDropped="Grid_ItemsDropped">
    <Columns>
        <DxGridDataColumn FieldName="ProductName" MinWidth="50" />
        <DxGridDataColumn FieldName="UnitPrice" DisplayFormat="c2" />
    </Columns>
</DxGrid>

@code {
    IGrid InStockGrid { get; set; }

    ObservableCollection<Product> InStockProducts { get; set; }
    ObservableCollection<Product> DiscontinuedProducts { get; set; }

    protected override async Task OnInitializedAsync() {
        var products = await NwindDataService.GetProductsAsync();
        InStockProducts = new ObservableCollection<Product>(products.Where(p => p.InStock));
        DiscontinuedProducts = new ObservableCollection<Product>(products.Where(p => p.Discontinued));
    }

    void Grid_ItemsDropped(GridItemsDroppedEventArgs evt) {
        var sourceProducts = GetProductCollection(evt.SourceComponent);
        RemoveDroppedItems(sourceProducts, evt.DroppedItems);

        var destinationProducts = GetProductCollection(evt.Grid);
        var targetProduct = (Product)evt.TargetItem;
        var index = targetProduct != null
            ? destinationProducts.IndexOf(targetProduct) + (evt.DropPosition == GridItemDropPosition.After ? 1 : 0)
            : destinationProducts.Count;

        InsertDroppedItems(destinationProducts, evt.DroppedItems, index);
    }

    ObservableCollection<Product> GetProductCollection(object grid) {
        return grid == InStockGrid ? InStockProducts : DiscontinuedProducts;
    }

    void RemoveDroppedItems(IList<Product> sourceProducts, IEnumerable<object> droppedItems) {
        foreach(var item in droppedItems)
            sourceProducts.Remove((Product)item);
    }

    void InsertDroppedItems(IList<Product> destinationProducts, IEnumerable<object> droppedItems, int index) {
        foreach(var item in droppedItems.Reverse())
            destinationProducts.Insert(index, (Product)item);
    }
}