How to: reorder items within wrappanel

[Daniel]

Hi,

it is posible to use RadListbox to reorder items by drag&drop whihe wrappanel is set as ItemsPanel?

<telerik:RadListBox ItemsSource="{Binding Items}" SelectedItem="{Binding SelectedItem, Mode=TwoWay}" ScrollViewer.HorizontalScrollBarVisibility="Disabled">
    <telerik:RadListBox.ItemContainerStyle>
      <Style TargetType="telerik:RadListBoxItem" BasedOn="{StaticResource RadListBoxItemStyle}">
        <Setter Property="telerik:DragDropManager.AllowCapturedDrag" Value="True" />
      </Style>
    </telerik:RadListBox.ItemContainerStyle>

    <telerik:RadListBox.DragVisualProvider>
      <telerik:ScreenshotDragVisualProvider />
    </telerik:RadListBox.DragVisualProvider>

    <telerik:RadListBox.DragDropBehavior>
      <telerik:ListBoxDragDropBehavior AllowReorder="True"  />
    </telerik:RadListBox.DragDropBehavior>

    <telerik:RadListBox.ItemsPanel>
      <ItemsPanelTemplate>
        <WrapPanel />
      </ItemsPanelTemplate>
    </telerik:RadListBox.ItemsPanel>

[Vladi]

Hello Daniel,

To enable the drag and drop reorder of items in RadListBox control when using WrapPanel as ItemsPanel you will need to create a CustomLinearDropVisualProvider that inherits LinearDropVisualProvider and override its GetLocation() method.

I created and attached a sample project for you showing the described approach.

Greetings,
Vladi
the Telerik team

[Moe]

I know this post is old, but I used the code in the attached project and encounter a bug.

The  LinearDropVisual disappear when scrolling to items beyond the screen (listbox with large items). Or if you scroll to items then drag the visual also disappear.

Any help is appreciated

 

[Polya]

Hello Mohamed Elsheihh,

This behavior of the RadWrapPanel is known to us and is related to the calculation of a container's position inside this panel. Unfortunately we cannot propose a workaround using a RadWrapPanel as it inherits from System.Windows.Controls.Panel.

Instead, I suggest using the VirtualizingWrapPanel instead where the position of a RadListBoxItem is differently calculated, because this panel inherits from System.Windows.Controls.VirtualizingPanel.

Hope this helps.

Regards,
Polya
Telerik