windowsforms-118077-controls-and-libraries-diagrams-examples-how-to-create-a-diagramshape-descendant-and-serialize-its-properties.md
This example demonstrates how to serialize custom data using DiagramControl‘s serialization mechanism. In the example, the DiagramShape.Content property of diagram shapes is loaded from data objects every time the diagram is shown. To associate shapes with data objects, the DatabaseObjectID property is added at the DiagramShape descendant level. To serialize this property along with standard DiagramShape properties, follow the steps below.
Note
In certain scenarios, it is easier to use the DiagramItem.Tag property to store custom data without creating DiagramShape descendants. In this case, no further steps are needed as the Tag property is serialized by default.
[XtraSerializableProperty]
public int DatabaseObjectID { get; set; }
DiagramControl.ItemTypeRegistrator.Register(typeof(DiagramShapeEx));
To allow end-users to edit your custom property in the Properties Panel, handle the DiagramControl.CustomGetEditableItemProperties event.
private void diagramControl1_CustomGetEditableItemProperties(object sender, DiagramCustomGetEditableItemPropertiesEventArgs e) {
if (e.Item is DiagramShapeEx) {
e.Properties.Add(TypeDescriptor.GetProperties(typeof(DiagramShapeEx))["DatabaseObjectID"]);
}
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;
namespace XtraDiagram.CustomShapeProperties {
static class Program {
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main() {
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using DevExpress.XtraDiagram;
using System.IO;
using DevExpress.Diagram.Core;
namespace XtraDiagram.CustomShapeProperties {
public partial class Form1 : DevExpress.XtraEditors.XtraForm {
const string diagramName = "diagram.xml";
List<DataObject> DataObjects = new List<DataObject>();
public Form1() {
InitializeComponent();
RegisterStencil();
DataObjects.Add(new DataObject { ID = 0, Content = "Start" });
DataObjects.Add(new DataObject { ID = 1, ParentID = 0, Content = "Node 1" });
DataObjects.Add(new DataObject { ID = 2, ParentID = 1, Content = "Node 1_1" });
DataObjects.Add(new DataObject { ID = 3, ParentID = 0, Content = "Node 2" });
DataObjects.Add(new DataObject { ID = 4, ParentID = 3, Content = "Node 2_1" });
}
protected override void OnLoad(EventArgs e) {
base.OnLoad(e);
if (!File.Exists(diagramName))
CreateDiagram();
else
LoadDiagram();
}
protected override void OnClosing(CancelEventArgs e) {
base.OnClosing(e);
diagramControl1.SaveDocument(diagramName);
}
void RegisterStencil() {
var stencil = new DevExpress.Diagram.Core.DiagramStencil("CustomStencil", "Custom Shapes");
var itemTool = new FactoryItemTool("CustomShape", () => "Custom Shape", diagram => { DiagramShapeEx customShape = new DiagramShapeEx() { Width = 100, Height = 50 }; return customShape; }, new System.Windows.Size(100, 50), false);
stencil.RegisterTool(itemTool);
DevExpress.Diagram.Core.DiagramToolboxRegistrator.RegisterStencil(stencil);
DiagramControl.ItemTypeRegistrator.Register(typeof(DiagramShapeEx));
}
private void LoadDiagram() {
try {
diagramControl1.LoadDocument(diagramName);
foreach (var item in diagramControl1.Items) {
var shape = item as DiagramShapeEx;
DataObject dataObject;
if (shape != null)
shape.Content = (dataObject = DataObjects.FirstOrDefault(x => x.ID == shape.DatabaseObjectID)) == null ? null : dataObject.Content;
}
}
catch (Exception e) {
CreateDiagram();
}
}
private void CreateDiagram() {
foreach (var dataObject in DataObjects) {
var shape = new DiagramShapeEx {
Shape = BasicShapes.Rectangle,
Size = new Size(150, 100),
DatabaseObjectID = dataObject.ID,
Content = dataObject.Content
};
diagramControl1.Items.Add(shape);
if (dataObject.ParentID != dataObject.ID)
diagramControl1.Items.Add(new DiagramConnector {
BeginItem = diagramControl1.Items.First(x => x is DiagramShapeEx && ((DiagramShapeEx)x).DatabaseObjectID == dataObject.ParentID),
EndItem = shape
});
}
diagramControl1.ApplyTreeLayout(Direction.Right);
}
private void OnShowingEditor(object sender, DiagramShowingEditorEventArgs e) {
e.Cancel = true;
}
private void diagramControl1_CustomGetEditableItemProperties(object sender, DiagramCustomGetEditableItemPropertiesEventArgs e) {
if (e.Item is DiagramShapeEx) {
e.Properties.Add(TypeDescriptor.GetProperties(typeof(DiagramShapeEx))["DatabaseObjectID"]);
}
}
}
public class DataObject {
public int ID { get; set; }
public int ParentID { get; set; }
public string Content { get; set; }
}
}
using DevExpress.Diagram.Core;
using DevExpress.Utils.Serializing;
using DevExpress.XtraDiagram;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
namespace XtraDiagram.CustomShapeProperties {
public class DiagramShapeEx : DiagramShape {
[XtraSerializableProperty]
public int DatabaseObjectID { get; set; }
static DiagramShapeEx() {
DiagramControl.ItemTypeRegistrator.Register(typeof(DiagramShapeEx));
}
}
}
Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Linq
Imports System.Text
Imports System.Windows.Forms
Imports DevExpress.XtraDiagram
Imports System.IO
Imports DevExpress.Diagram.Core
Namespace XtraDiagram.CustomShapeProperties
Partial Public Class Form1
Inherits DevExpress.XtraEditors.XtraForm
Private Const diagramName As String = "diagram.xml"
Private DataObjects As New List(Of DataObject)()
Public Sub New()
InitializeComponent()
RegisterStencil()
DataObjects.Add(New DataObject With {.ID = 0, .Content = "Start"})
DataObjects.Add(New DataObject With {.ID = 1, .ParentID = 0, .Content = "Node 1"})
DataObjects.Add(New DataObject With {.ID = 2, .ParentID = 1, .Content = "Node 1_1"})
DataObjects.Add(New DataObject With {.ID = 3, .ParentID = 0, .Content = "Node 2"})
DataObjects.Add(New DataObject With {.ID = 4, .ParentID = 3, .Content = "Node 2_1"})
End Sub
Protected Overrides Sub OnLoad(ByVal e As EventArgs)
MyBase.OnLoad(e)
If Not File.Exists(diagramName) Then
CreateDiagram()
Else
LoadDiagram()
End If
End Sub
Protected Overrides Sub OnClosing(ByVal e As CancelEventArgs)
MyBase.OnClosing(e)
diagramControl1.SaveDocument(diagramName)
End Sub
Private Sub RegisterStencil()
Dim stencil = New DevExpress.Diagram.Core.DiagramStencil("CustomStencil", "Custom Shapes")
stencil.RegisterTool(New FactoryItemTool("CustomShape", Function() "Custom Shape", Function(diagram) New DiagramShapeEx(), New System.Windows.Size(230, 110), False))
DevExpress.Diagram.Core.DiagramToolboxRegistrator.RegisterStencil(stencil)
DiagramControl.ItemTypeRegistrator.Register(GetType(DiagramShapeEx))
End Sub
Private Sub LoadDiagram()
Try
diagramControl1.LoadDocument(diagramName)
For Each item In diagramControl1.Items
Dim shape = TryCast(item, DiagramShapeEx)
Dim dataObject As DataObject
If shape IsNot Nothing Then
dataObject = DataObjects.FirstOrDefault(Function(x) x.ID = shape.DatabaseObjectID)
shape.Content = If(dataObject Is Nothing, Nothing, dataObject.Content)
End If
Next item
Catch e As Exception
CreateDiagram()
End Try
End Sub
Private Sub CreateDiagram()
For Each dataObject In DataObjects
Dim shape = New DiagramShapeEx With {.Shape = BasicShapes.Rectangle, .Size = New Size(150, 100), .DatabaseObjectID = dataObject.ID, .Content = dataObject.Content}
diagramControl1.Items.Add(shape)
If dataObject.ParentID <> dataObject.ID Then
diagramControl1.Items.Add(New DiagramConnector With {.BeginItem = diagramControl1.Items.First(Function(x) TypeOf x Is DiagramShapeEx AndAlso CType(x, DiagramShapeEx).DatabaseObjectID = dataObject.ParentID), .EndItem = shape})
End If
Next dataObject
diagramControl1.ApplyTreeLayout(Direction.Right)
End Sub
Private Sub OnShowingEditor(ByVal sender As Object, ByVal e As DiagramShowingEditorEventArgs) Handles diagramControl1.ShowingEditor
e.Cancel = True
End Sub
Private Sub diagramControl1_CustomGetEditableItemProperties(sender As Object, e As DiagramCustomGetEditableItemPropertiesEventArgs) Handles diagramControl1.CustomGetEditableItemProperties
If TypeOf e.Item Is DiagramShapeEx Then
e.Properties.Add(TypeDescriptor.GetProperties(GetType(DiagramShapeEx))("DatabaseObjectID"))
End If
End Sub
End Class
Public Class DataObject
Public Property ID() As Integer
Public Property ParentID() As Integer
Public Property Content() As String
End Class
End Namespace
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Windows.Forms
Namespace XtraDiagram.CustomShapeProperties
Friend NotInheritable Class Program
Private Sub New()
End Sub
''' <summary>
''' The main entry point for the application.
''' </summary>
<STAThread> _
Shared Sub Main()
Application.EnableVisualStyles()
Application.SetCompatibleTextRenderingDefault(False)
Application.Run(New Form1())
End Sub
End Class
End Namespace
Imports DevExpress.Diagram.Core
Imports DevExpress.Utils.Serializing
Imports DevExpress.XtraDiagram
Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Linq
Imports System.Text
Namespace XtraDiagram.CustomShapeProperties
Public Class DiagramShapeEx
Inherits DiagramShape
<XtraSerializableProperty> _
Public Property DatabaseObjectID() As Integer
Shared Sub New()
DiagramControl.ItemTypeRegistrator.Register(GetType(DiagramShapeEx))
End Sub
End Class
End Namespace