Class GraphLayoutManager

The GraphLayoutManager defines the base class used for implementing layout managers for diagrams composed of nodes that form a connected graph. The GraphLayoutManager provides the necessary foundation for initializing, validating and creating the diagram graph. The GraphLayoutManager also implements the infrastructure for positioning diagram nodes using the specialized layout strategies provided by custom layout managers. LayoutManager DirectedTreeLayoutManager RadialTreeLayoutManager

Inheritance
System.Object
LayoutManager
GraphLayoutManager
DirectedTreeLayoutManager
HierarchicLayoutManager
SymmetricLayoutManager
Inherited Members
Namespace: Syncfusion.Windows.Forms.Diagram
Assembly: Syncfusion.Diagram.Base.dll
Syntax
public abstract class GraphLayoutManager : LayoutManager

Constructors

GraphLayoutManager()

Initializes a new instance of the GraphLayoutManager class.

Declaration
public GraphLayoutManager()

GraphLayoutManager(Model, Single, Single)

Initializes a new instance of the GraphLayoutManager class.

Declaration
public GraphLayoutManager(Model model, float fHorizontalSpacing, float fVerticalSpacing)
Parameters
Type Name Description
Model model

The diagram Model.
System.Single fHorizontalSpacing

The horizontal spacing between nodes.
System.Single fVerticalSpacing

The vertical spacing between nodes.

Fields

m_fXBorder

Declaration
protected float m_fXBorder
Field Value
Type
System.Single

m_fYBorder

Declaration
protected float m_fYBorder
Field Value
Type
System.Single

m_fYHighest

Declaration
protected float m_fYHighest
Field Value
Type
System.Single

Properties

HorizontalSpacing

Gets or sets the horizontal offset between adjacent nodes.

Declaration
public float HorizontalSpacing { get; set; }
Property Value
Type
System.Single

ImprovePerformance

Gets or sets a value indicating whether performance can be improved.

Declaration
public bool ImprovePerformance { get; set; }
Property Value
Type
System.Boolean

PassedNodes

Gets or sets the passed node collection where key is node fullname and value - node reference.

Declaration
protected Hashtable PassedNodes { get; set; }
Property Value
Type Description
System.Collections.Hashtable

The passed nodes.

SelectedNode

Gets or sets the current selected node while generation node graph.

Declaration
protected object SelectedNode { get; set; }
Property Value
Type Description
System.Object

The selected node.

VerticalSpacing

Gets or sets the vertical offset between adjacent nodes.

Declaration
public float VerticalSpacing { get; set; }
Property Value
Type
System.Single

Methods

DoGraphLayout()

Applies a custom layout management strategy on the diagram.

Declaration
protected abstract void DoGraphLayout()

OnPreferredLayout(PreferredLayoutEventArgs)

Occurs before a node(or graph) is positioned.

Declaration
protected virtual void OnPreferredLayout(PreferredLayoutEventArgs evtargs)
Parameters
Type Name Description
PreferredLayoutEventArgs evtargs

Event arguments.
Remarks

This method can be overridden in derived classes.

PreferredLayoutEventArgs

UpdateLayout(NodeCollection)

Updates the layout of the given nodes.

Declaration
protected bool UpdateLayout(NodeCollection nodesToLayout)
Parameters
Type Name Description
NodeCollection nodesToLayout

The nodes to layout.
Returns
Type Description
System.Boolean

True if changes were made; otherwise False.

UpdateLayout(Object)

Updates the layout of the nodes in the model.

Declaration
public override bool UpdateLayout(object contextInfo)
Parameters
Type Name Description
System.Object contextInfo

Provides context information to help with updating the layout.
Returns
Type Description
System.Boolean

True if changes were made; otherwise False.
Overrides

Events

PreferredLayout

Occurs before a node graph is positioned.

Declaration
public event PreferredLayoutEventHandler PreferredLayout
Event Type
Type
PreferredLayoutEventHandler
Remarks

Handling the PreferredLayout event provides users with the ability to examine the bounds used for laying out the node graph and specify a different bounds if necessary.