C

FocusIndicatorManager<T>

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A ModelManager<T> implementation that manages the visual decoration of the focused element in a canvas.
Inheritance Hierarchy

Remarks

For the item that should be focused, this class uses the ILookup mechanism of the item to look up an IFocusRenderer<T> implementation which will render the decoration in the canvas.

The default implementation of the renderer is using the yfiles-focus-template CSS class and possibly one of the following CSS classes depending on the item type: yfiles-node-focus-template, yfiles-edge-focus-template, yfiles-label-focus-template, yfiles-port-focus-template.

Type Parameters

T

The type of the items.

See Also

An overview of the different CSS styling options is presented in detail in the section Using CSS Styling for the Indicators .

API

FocusIndicatorManager, HighlightIndicatorManager, SelectionIndicatorManager

Members

Show:

Constructors

FocusIndicatorManager

()
Creates a new instance.

If a new FocusIndicatorManager<T> instance is set to a GraphComponent's focusIndicatorManager property, the old instance is uninstalled and the new instance is installed automatically.

If a new FocusIndicatorManager<T> instance is not set via the focusIndicatorManager property, it is important to call the install life-cycle method.

Properties

canvasComponent

: CanvasComponent
Gets the canvas instance this instance is managing.
The canvas must be set to a non-null value in install and set back to null in uninstall.
final

enabled

: boolean
Gets or sets whether this ModelManager<T> is enabled.

If the manager is disabled, it will not install the IRenderTreeElements into the associated CanvasComponent.

The default is true, i.e. this manager is enabled by default.

final

Property Value

true if enabled; false otherwise.

focused

: boolean
Gets or sets a value indicating whether the container this manager is installed in currently is focused.
final

Property Value

true if the container is currently focused; false otherwise. Depending on the showFocusPolicy, this will influence the visibility of the rendering.

focusedItem

: T
Gets or sets the focused item, updates the canvas, and fires the corresponding event.
final

Property Value

The focused item, which can be null, when no item has or should have focus.

See Also

Developer's Guide

showFocusPolicy

: ShowFocusPolicy
Gets or sets the policy for when the focus indicator should be visible.
The default is WHEN_USING_KEYBOARD.
conversionfinal

Property Value

The policy. Changing this property influences the visibility of the rendering depending on the current value of the focused and usingKeyboard properties.

See Also

Developer's Guide

usingKeyboard

: boolean
Gets or sets a value that determines whether the user is currently using the keyboard to control the focusedItem.
When showFocusPolicy is set to WHEN_USING_KEYBOARD, this property controls whether to show the focus indicator. Note that focused needs to be set to true, too, in order for the indication to be displayed. This property gets automatically reset to false, when the user interacts with a pointer device and pointer-down is triggered.
final

See Also

Developer's Guide
API
showFocusPolicy

Methods

addItem

(item: T): IRenderTreeElement
protected
Overridden to do nothing.
protected

Parameters

item: T
The item to add, which is ignored in this implementation.

Return Value

IRenderTreeElement
Always returns null as no action is performed.

getRenderer

(item: T): IObjectRenderer<T>
protected
Called by installItem to retrieve the renderer for a given item.
This implementation uses the lookup of the item to retrieve an IFocusRenderer<T> instance.
protected

Parameters

item: T
The item to find a renderer for.

Return Value

IObjectRenderer<T>
A renderer or null

getRenderTreeGroup

(item: T): IRenderTreeGroup
protected
Called by installItem to retrieve the render tree group for a given item.
This implementation always returns the focusGroup of the canvasComponent of this instance.
protected

Parameters

item: T
The item to find a render tree group for.

Return Value

IRenderTreeGroup
An IRenderTreeGroup or null

install

(canvasComponent: CanvasComponent)
Installs this instance in the given CanvasComponent instance.

If this manager instance is set to a CanvasComponent instance using one of the properties focusIndicatorManager, selectionIndicatorManager, or highlightIndicatorManager, this method is called automatically.

In all other cases, this method must be called before using this manager instance.

Overriders must either call the base implementation or set the canvasComponent.

Parameters

canvasComponent: CanvasComponent
The CanvasComponent instance to install this manager instance in.

installItem

(item: T): IRenderTreeElement
protected
Installs a member of the collection into the canvas using the IObjectRenderer<T> which is returned by getRenderer.
protected

Parameters

item: T
The member to install.

Return Value

IRenderTreeElement
The new render tree element or null if the item was not installed.

onDisabled

()
protected
Called when this manager gets disabled.
protected

onEnabled

()
protected
Called when this manager gets enabled.
protected

onFocusedChanged

()
protected
Called when the focused property has changed.
This implementation determines whether to actually show the focus depending on the current settings of showFocusPolicy, usingKeyboard and focused
protected

See Also

API
focused

onFocusedItemChanged

(evt: any)
protected
Called when the focused item has changed.
This method raises the focused-item-changed event. Subclasses overriding this method should make sure to invoke the superclass implementation.
protected

Parameters

evt: any
a description of the event

See Also

API
focusedItem, focused-item-changed

onUsingKeyboardChanged

()
protected
Called when the usingKeyboard property has changed.
This implementation determines whether to actually show the focus depending on the current settings of showFocusPolicy, usingKeyboard and focused.
protected

See Also

API
usingKeyboard

removeItem

(item: T)
protected
Overridden to do nothing.
protected

Parameters

item: T
The item to remove.

uninstall

(canvasComponent: CanvasComponent)
Uninstalls this instance from the given CanvasComponent instance.

If this manager instance has been set to a CanvasComponent instance using one of the properties focusIndicatorManager, selectionIndicatorManager, or highlightIndicatorManager, this method is called automatically when the property value is changed.

In all other cases, this method must be called when this manager instance is not used anymore.

Overriders must either call the base implementation or set the canvasComponent to null.

Parameters

canvasComponent: CanvasComponent
The CanvasComponent to remove this manager instance from.

uninstallItem

(renderTreeElement: IRenderTreeElement)
protected
Removes the given IRenderTreeElement.
protected

Parameters

renderTreeElement: IRenderTreeElement
The render tree element that has been associated with the renderer.

See Also

API
remove

Events

'focused-item-changed'

: function(any, this): void
Occurs when the focusedItem property has been changed.

Properties of

function(any, this): void