Generating Diagrams from a Data Source

• Aug 24, 2021
• 2 minutes to read

The DiagramDataBindingBehavior class provides the data binding behavior for the DiagramControl. To bind the DiagramControl to data, open its Smart Tag panel and select DiagramDataBindingBehavior.

The following XAML will be generated.

XAML

<dxdiag:DiagramControl SelectedStencils="BasicShapes, BasicFlowchartShapes">
    <dxmvvm:Interaction.Behaviors>
        <dxdiag:DiagramDataBindingBehavior />
    </dxmvvm:Interaction.Behaviors>
</dxdiag:DiagramControl>

To configure the data source, go to the Smart Tag panel’s MVVM Behaviors tab.

The following table lists the properties used to map a diagram to data.

Member	Description
DiagramDataBindingBehaviorBase.ItemsSource	Specifies the path to a collection of diagram items.
DiagramDataBindingBehavior.ConnectorsSource	Specifies the path to a collection of objects that represent connectors.
DiagramDataBindingBehavior.ConnectorFromMember	Specifies the name of the data field that identifies the item to use as a connector’s start item.
DiagramDataBindingBehavior.ConnectorToMember	Specifies the name of the data field that identifies the item to use as a connector’s end item.

Note

Limitations The DiagramDataBindingController can only get values from strongly typed objects. Binding to dynamic properties is not supported.

Tip

The Item Template Designer allows you to design templates for diagram items and connectors at design time.

The following example demonstrates the DiagramControl bound to sample data.

XAML

<Window ...
        xmlns:dxdiag="http://schemas.devexpress.com/winfx/2008/xaml/diagram" 
        xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm" >
    <Window.DataContext>
        <local:ViewModel/>
    </Window.DataContext>
    <Grid>
        <dxdiag:DiagramControl SelectedStencils="BasicShapes, BasicFlowchartShapes">
            <dxmvvm:Interaction.Behaviors>
                <dxdiag:DiagramDataBindingBehavior ItemsSource="{Binding Items}" ConnectorsSource="{Binding Connections}" KeyMember="Id" 
                                                   ConnectorFromMember="From" ConnectorToMember="To" LayoutKind="Circular">
                    <dxdiag:DiagramDataBindingBehavior.TemplateDiagram>
                        <dxdiag:DiagramControl SelectedStencils="TemplateDesigner" ShowPageBreaks="false">
                            <dxdiag:DiagramContainer  Height="50"  ThemeStyleId="Variant1" Width="100">
                                <dxdiag:DiagramShape StrokeThickness="0" Height="50"  Width="100">
                                    <dxdiag:DiagramShape.Bindings>
                                        <dxdiag:DiagramBinding Expression="Name" PropertyName="Content" />
                                    </dxdiag:DiagramShape.Bindings>
                                </dxdiag:DiagramShape>
                            </dxdiag:DiagramContainer>
                        </dxdiag:DiagramControl>
                    </dxdiag:DiagramDataBindingBehavior.TemplateDiagram>
                </dxdiag:DiagramDataBindingBehavior>
            </dxmvvm:Interaction.Behaviors>
        </dxdiag:DiagramControl>
    </Grid></Window>

C#

public class ViewModel {
    public class ViewModel {
        public List<Item> Items { get; set; }
        public List<Link> Connections { get; set; }
        public ViewModel() {
            Items = new List<Item>();
            for (int i = 0; i < 5; i++)
                Items.Add(new Item { Id = i, Name = "Item " + i });
            Connections = new List<Link>();
            for (int i = 0; i < 4; i++)
                Connections.Add(new Link { From = Items[i].Id, To = Items[i+1].Id });
            Connections.Add(new Link { From = Items[4].Id, To = Items[0].Id });
        }
    }

C#

public class Item {
        public int Id { get; set; }
        public string Name { get; set; }
    }

    public class Link {
        public object From { get; set; }
        public object To { get; set; }
    }