Change the Colors of the Shape Dropped from RadDiagram Toolbox

Environment

Product	Version
RadDiagram for WPF	2023.2.606

Description

How to change the background and border brush a shape dragged from the RadDiagramToolBox, when the shape get dropped onto the RadDiagram surface.

Solution

You can subscribe to the SerializationService.Default.ItemSerializing event. In the event handler, you can update the "Background" and "BorderBrush" settings of the SerializationInfo object.

public MainWindow() 
{ 
    InitializeComponent(); 
    SerializationService.Default.ItemSerializing += Default_ItemSerializing; 
} 
 
private void Default_ItemSerializing(object sender, SerializationEventArgs<IDiagramItem> e) 
{ 
    var shape = e.Entity as RadDiagramShape; 
    if (shape != null && shape.ParentOfType<RadDiagramToolbox>() != null) 
    { 
        e.SerializationInfo["Background"] = new SolidColorBrush((Color)ColorConverter.ConvertFromString("#8EC251")); 
        e.SerializationInfo["BorderBrush"] = new SolidColorBrush((Color)ColorConverter.ConvertFromString("#8EC251")); 
    } 
} 

In case you need to change also the colors of the shape when displayed inside the RadDiagramToolBox, then you can add an implicit style in the RadDiagramToolBox.Resources tag and target the RadDiagramShape controls.

   <telerik:RadDiagramToolbox.Resources> 
    <Style TargetType="telerik:RadDiagramShape"> 
        <Setter Property="Background" Value="#8EC251" /> 
        <Setter Property="BorderBrush" Value="#8EC251" /> 
    </Style> 
</telerik:RadDiagramToolbox.Resources>