Class LayoutManager

Base class for layout managers.

Inheritance

System.Object

LayoutManager

GraphLayoutManager

TableLayoutManager

Namespace: Syncfusion.Windows.Forms.Diagram

Assembly: Syncfusion.Diagram.Base.dll

Syntax

public abstract class LayoutManager : Component

Remarks

This class provides the basic plumbing for layout managers. A layout manager is an object that controls the positioning of nodes in a model. Each layout manager object is attached to a single model by the Model property.

Layout managers can operate one of two modes: manual or auto-update. When the AutoLayout flag is set to True, the layout manager responds to events in the model by automatically repositioning nodes in the model. The UpdateLayout(Object) method can be called at any time to reposition the nodes in the model. If the AutoLayout flag is False, then UpdateLayout must be called manually in order to update the layout of nodes in the model.

Model

Constructors

LayoutManager()

Initializes a new instance of the LayoutManager class.

Declaration

public LayoutManager()

LayoutManager(Model)

Initializes a new instance of the LayoutManager class.

Declaration

public LayoutManager(Model model)

Parameters

Type	Name	Description
Model	model	The model.

Fields

autoLayoutFlag

Flag indicating if layout is to be updated automatically.

Declaration

protected bool autoLayoutFlag

Field Value

Type
System.Boolean

LayoutUpdated

Fired after the layout has been updated by the layout manager.

Declaration

public EventHandler LayoutUpdated

Field Value

Type
System.EventHandler

mdl

Reference to model and layout.

Declaration

protected Model mdl

Field Value

Type
Model

Properties

AutoLayout

Gets or sets a value indicating whether the layout manager automatically updates the layout of the model.

Declaration

public bool AutoLayout { get; set; }

Property Value

Type
System.Boolean

LeftMargin

Gets or Sets the left margin for the layout manager.

Declaration

public float LeftMargin { get; set; }

Property Value

Type
System.Single

Model

Gets or sets the model attached to this layout manager.

Declaration

public Model Model { get; set; }

Property Value

Type
Model

Remarks

The model referenced by this property is updated when the UpdateLayout method is called.

Nodes

Gets the nodes collection by who will apply layout.

Declaration

public NodeCollection Nodes { get; }

Property Value

Type	Description
NodeCollection	The nodes collection.

TopMargin

Gets or Sets the top margin for the layout manager.

Declaration

public float TopMargin { get; set; }

Property Value

Type
System.Single

UpdatingLayout

Gets or sets a value indicating whether layout update state.

Declaration

protected bool UpdatingLayout { get; set; }

Property Value

Type
System.Boolean

Methods

OnConnectionsChanged(CollectionExEventArgs)

Called when connection collections is changed.

Declaration

protected virtual void OnConnectionsChanged(CollectionExEventArgs evtArgs)

Parameters

Type	Name	Description
CollectionExEventArgs	evtArgs	The CollectionExEventArgs instance containing the event data.

OnLayoutUpdated(EventArgs)

Called after the layout has been updated by the layout manager.

Declaration

protected virtual void OnLayoutUpdated(EventArgs evtArgs)

Parameters

Type	Name	Description
System.EventArgs	evtArgs	Event arguments.

OnNodeCollectionChanged(CollectionExEventArgs)

Called when nodes are added or removed from the model.

Declaration

protected virtual void OnNodeCollectionChanged(CollectionExEventArgs evtArgs)

Parameters

Type	Name	Description
CollectionExEventArgs	evtArgs	Event arguments.

OnPropertyChanged(PropertyChangedEventArgs)

Called when one or more nodes in the model are has change properties.

Declaration

protected virtual void OnPropertyChanged(PropertyChangedEventArgs evtArgs)

Parameters

Type	Name	Description
PropertyChangedEventArgs	evtArgs	The event args.

UpdateLayout(Object)

Updates the layout of the nodes in the model.

Declaration

public abstract 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.