C

PortStyleBase<TVisual>
abstract

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An abstract base class that makes it possible to easily implement a custom IPortStyle.
ImplementsInheritance Hierarchy

Remarks

Only createVisual and getBounds need to be implemented by subclasses, however to improve rendering performance it is highly recommended to implement at least updateVisual, too.

Unlike a direct IPortStyle implementation, PortStyleBase<TVisual> does not expose a separate IPortStyleRenderer. The base class uses a fixed renderer and simply forwards its calls back to the style instance.

Note that if your subclass has private fields (defined with JavaScript's # name syntax), the clone method needs to be overridden for the cloning to work properly.

Type Parameters

TVisual

The optional type of the created and updated by the and methods. This type argument can be omitted, but specifying a more concrete type helps conveniently implementing with TypeScript.

See Also

Developer's Guide

Demos

Shows how to create custom styles for nodes, edges, labels, ports, and edge arrows.
Visualize a port as a basic circle shape

Members

Show:

Constructors

PortStyleBase

()
protected
Initializes a new instance of the PortStyleBase<TVisual> class.

Properties

renderer

: IPortStyleRenderer
readonly
Gets the renderer implementation for this instance.
The private implementation will delegate all API calls back to this instance.
readonlyfinal

Methods

clone

(): Object
Creates a new object that is a copy of the current instance.

Immutable subclasses should consider returning this for the best performance.

The base class implementation creates a simple shallow clone that copies all own properties to a new instance. This will not work for classes that use private fields or properties (defined with JavaScript's # name syntax) as no constructors will be run and implementations like this cannot be accessed from outside the classes that declare them.

Classes that use private members or require special initialization must override this method and manually create a new instance or call super.clone() and then explicitly copy the private fields and properties explicitly.

Return Value

Object
A new object that is a copy of this instance using a memberwise clone.

createVisual

(context: IRenderContext, port: IPort): TVisual
protectedabstract
Creates the visual.
This method is called in response to a createVisual call to the instance that has been queried from the renderer.
protectedabstract

Parameters

context: IRenderContext
The render context.
port: IPort
The port to which this style instance is assigned.

Return Value

TVisual
The visual as required by the createVisual interface.

See Also

API
updateVisual

getBounds

(context: ICanvasContext, port: IPort): Rect
protectedabstract
Returns the bounds of the visual for the port in the given context.
protectedabstract

Parameters

context: ICanvasContext
The canvas context.
port: IPort
The port to which this style instance is assigned.

Return Value

Rect
The visual bounds of the visual representation.

isHit

(
context: IInputModeContext
location: Point
port: IPort
): boolean
protected
Determines whether the visual representation of the port has been hit at the given location.

This method is called in response to a isHit call to the instance that has been queried from the renderer.

This implementation uses the bounds to determine whether the port has been hit.

protected

Parameters

context: IInputModeContext
The input mode context.
location: Point
The point to test.
port: IPort
The port to which this style instance is assigned.

Return Value

boolean
true if the specified port representation is hit; false otherwise.

isInBox

(
context: IInputModeContext
rectangle: Rect
port: IPort
): boolean
protected
Determines whether the visualization for the specified port is included in the marquee selection.

This method is called in response to a isInBox call to the instance that has been queried from the renderer.

This implementation simply tests whether the bounds intersect the marquee box.

protected

Parameters

context: IInputModeContext
The input mode context.
rectangle: Rect
The marquee selection box.
port: IPort
The port to which this style instance is assigned.

Return Value

boolean
true if the specified port is visible and selected by the marquee rectangle; false otherwise.

isInPath

(
context: IInputModeContext
path: GeneralPath
port: IPort
): boolean
protected
Determines whether the visualization for the specified port is included in the lasso selection.

This method is called in response to a isInPath call to the instance that has been queried from the renderer.

This implementation simply tests whether the bounds intersect the lasso path.

protected

Parameters

context: IInputModeContext
The input mode context.
path: GeneralPath
The lasso selection path.
port: IPort
The port to which this style instance is assigned.

Return Value

boolean
true if the specified port is visible and selected by the lasso path; false otherwise.

isVisible

(
context: ICanvasContext
rectangle: Rect
port: IPort
): boolean
protected
Determines whether the visualization for the specified port is visible in the context.
This method is called in response to a isVisible call to the instance that has been queried from the renderer. This implementation simply tests whether the bounds intersect the clip.
protected

Parameters

context: ICanvasContext
The canvas context.
rectangle: Rect
The clipping rectangle.
port: IPort
The port to which this style instance is assigned.

Return Value

boolean
true if the specified port is visible in the clipping rectangle; false otherwise.

lookup

(port: IPort, type: Constructor): any
protected
Performs the lookup operation for the getContext that has been queried from the renderer.

This implementation yields null for everything but:

For these interfaces an implementation will be returned that delegates to the methods in this instance.

protected

Parameters

port: IPort
The port to use for the context lookup.
type: Constructor
The type to query.

Return Value

any
An implementation of the type or null.

updateVisual

(
context: IRenderContext
oldVisual: TVisual
port: IPort
): TVisual
protected
Updates the visual previously created by createVisual.
This method is called in response to a updateVisual call to the instance that has been queried from the renderer. This implementation simply delegates to createVisual so subclasses should override to improve rendering performance.
protected

Parameters

context: IRenderContext
The render context.
oldVisual: TVisual
The visual that has been created in the call to createVisual.
port: IPort
The port to which this style instance is assigned.

Return Value

TVisual
The visual as required by the createVisual interface.

See Also

API
createVisual