Applies to: Nevron Diagram for .NET
How to implement show-hide (expand/collapse) on a tree diagram?
The following code example will generate a random tree diagram with show-hide subtree decorator for each shape that has children:
[C#]
using Nevron.GraphicsCore;
using Nevron.Diagram;
using Nevron.Diagram.Shapes;
using Nevron.Diagram.WinForm;
using Nevron.Diagram.Templates;
using Nevron.Diagram.Filters;
using Nevron.Diagram.Layout;
using Nevron.Diagram.DataStructures;
…
view.BeginInit();
view.Dock = DockStyle.Fill;
view.ViewLayout = ViewLayout.Fit;
view.Grid.Visible = false;
view.GlobalVisibility.ShowPorts = false;
document.BeginInit();
// create a random tree
NGenericTreeTemplate treeTemplate = new NGenericTreeTemplate();
treeTemplate.BranchNodes = 3;
treeTemplate.VerticesSize = new NSizeF(50, 50);
treeTemplate.Balanced = false;
treeTemplate.Levels = 5;
treeTemplate.Create(document);
// add show-hide subtree decorator for each shape that has children
foreach (NShape shape in document.ActiveLayer.Children(NFilters.Shape2D))
{
if (shape.GetOutgoingShapes().Count == 0)
continue;
// create the decorators collection
shape.CreateShapeElements(ShapeElementsMask.Decorators);
NShowHideSubtreeDecorator decorator = new NShowHideSubtreeDecorator();
decorator.Offset = new NSizeF(-11, 11);
decorator.Size = new NSizeF(15, 15);
decorator.Alignment = new NContentAlignment(ContentAlignment.TopLeft);
shape.Decorators.AddChild(decorator);
}
document.AutoBoundsMinSize = new NSizeF(400, 400);
// layout with a layered tree layout
NLayoutContext context = new NLayoutContext();
context.GraphAdapter = new NShapeGraphAdapter(true);
context.BodyAdapter = new NShapeBodyAdapter(document);
context.BodyContainerAdapter = new NDrawingBodyContainerAdapter(document);
NLayeredTreeLayout layout = new NLayeredTreeLayout();
layout.VertexSpacing = 50;
layout.LayerSpacing = 50;
layout.Layout(document.ActiveLayer.Children(null), context);
// size to visible shapes
document.SizeToContent(document.AutoBoundsMinSize, document.AutoBoundsPadding, NFilters.Visible);
document.EndInit();
view.EndInit();
[VB.NET]
Imports Nevron.GraphicsCore
Imports Nevron.Diagram
Imports Nevron.Diagram.Shapes
Imports Nevron.Diagram.WinForm
Imports Nevron.Diagram.Templates
Imports Nevron.Diagram.Filters
Imports Nevron.Diagram.Layout
Imports Nevron.Diagram.DataStructures
…
view.BeginInit()
view.Dock = DockStyle.Fill
view.ViewLayout = ViewLayout.Fit
view.Grid.Visible = False
view.GlobalVisibility.ShowPorts = False
document.BeginInit()
' create a random tree
Dim treeTemplate As New NGenericTreeTemplate()
treeTemplate.BranchNodes = 3
treeTemplate.VerticesSize = New NSizeF(50, 50)
treeTemplate.Balanced = False
treeTemplate.Levels = 5
treeTemplate.Create(document)
' add show-hide subtree decorator for each shape that has children
For Each shape As NShape In document.ActiveLayer.Children(NFilters.Shape2D)
If shape.GetOutgoingShapes().Count = 0 Then
Continue For
End If
' create the decorators collection
shape.CreateShapeElements(ShapeElementsMask.Decorators)
Dim decorator As New NShowHideSubtreeDecorator()
decorator.Offset = New NSizeF(-11, 11)
decorator.Size = New NSizeF(15, 15)
decorator.Alignment = New NContentAlignment(ContentAlignment.TopLeft)
shape.Decorators.AddChild(decorator)
Next
document.AutoBoundsMinSize = New NSizeF(400, 400)
' layout with a layered tree layout
Dim context As New NLayoutContext()
context.GraphAdapter = New NShapeGraphAdapter(True)
context.BodyAdapter = New NShapeBodyAdapter(document)
context.BodyContainerAdapter = New NDrawingBodyContainerAdapter(document)
Dim layout As New NLayeredTreeLayout()
layout.VertexSpacing = 50
layout.LayerSpacing = 50
layout.Layout(document.ActiveLayer.Children(Nothing), context)
' size to visible shapes
document.SizeToContent(document.AutoBoundsMinSize, document.AutoBoundsPadding, NFilters.Visible)
document.EndInit()
view.EndInit()
For more detailed information about Decorators, take a look at the Help Documentation:
Diagram for .NET > User's Guide > Document Object Model > Models > Shapes > Decorators
Related examples:
Diagram Windows Forms: Document Object Model - Shapes - Decorators folder
Diagram Web Forms: Show/Hide Subtree Decorator
Article ID: 99, Created On: 10/21/2010, Modified: 12/29/2010