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Class

Renderer (engine/view)

@ckeditor/ckeditor5-engine/src/view/renderer

class
See source

Renderer is responsible for updating the DOM structure and the DOM selection based on the information about updated view nodes. In other words, it renders the view to the DOM.

Its main responsibility is to make only the necessary, minimal changes to the DOM. However, unlike in many virtual DOM implementations, the primary reason for doing minimal changes is not the performance but ensuring that native editing features such as text composition, autocompletion, spell checking, selection's x-index are affected as little as possible.

Renderer uses DomConverter to transform view nodes and positions to and from the DOM.

Filtering

Properties

  • readonly

    domConverter : DomConverter

    See source

    Converter instance.

  • readonly

    domDocuments : Set<Document>

    See source

    Set of DOM Documents instances.

  • readonly observable

    isComposing : boolean

    See source

    True if composition is in progress inside the document.

    This property is bound to the Document#isComposing property.

  • readonly observable

    isFocused : boolean

    See source

    Indicates if the view document is focused and selection can be rendered. Selection will not be rendered if this is set to false.

  • readonly observable

    isSelecting : boolean

    See source

    Indicates whether the user is making a selection in the document (e.g. holding the mouse button and moving the cursor). When they stop selecting, the property goes back to false.

    Note: In some browsers, the renderer will stop rendering the selection and inline fillers while the user is making a selection to avoid glitches in DOM selection (https://github.com/ckeditor/ckeditor5/issues/10562, https://github.com/ckeditor/ckeditor5/issues/10723).

  • readonly

    markedAttributes : Set<Element>

    See source

    Set of nodes which attributes changed and may need to be rendered.

  • readonly

    markedChildren : Set<Element>

    See source

    Set of elements which child lists changed and may need to be rendered.

  • readonly

    markedTexts : Set<Node>

    See source

    Set of text nodes which text data changed and may need to be rendered.

  • readonly

    selection : DocumentSelection

    See source

    View selection. Renderer updates DOM selection based on the view selection.

  • private

    _fakeSelectionContainer : null | HTMLElement

    See source

    DOM element containing fake selection.

  • private

    _inlineFiller : null | Text

    See source

    The text node in which the inline filler was rendered.

Methods

  • constructor( domConverter, selection )

    See source

    Creates a renderer instance.

    Parameters

    domConverter : DomConverter

    Converter instance.

    selection : DocumentSelection

    View selection.

  • inherited

    bind( bindProperties ) → MultiBindChain

    See source

    Binds observable properties to other objects implementing the Observable interface.

    Read more in the dedicated guide covering the topic of property bindings with some additional examples.

    Consider two objects: a button and an associated command (both Observable).

    A simple property binding could be as follows:

    button.bind( 'isEnabled' ).to( command, 'isEnabled' );

    or even shorter:

    button.bind( 'isEnabled' ).to( command );

    which works in the following way:

    • button.isEnabled instantly equals command.isEnabled,
    • whenever command.isEnabled changes, button.isEnabled will immediately reflect its value.

    Note: To release the binding, use unbind.

    You can also "rename" the property in the binding by specifying the new name in the to() chain:

    button.bind( 'isEnabled' ).to( command, 'isWorking' );

    It is possible to bind more than one property at a time to shorten the code:

    button.bind( 'isEnabled', 'value' ).to( command );

    which corresponds to:

    button.bind( 'isEnabled' ).to( command );
button.bind( 'value' ).to( command );

    The binding can include more than one observable, combining multiple data sources in a custom callback:

    button.bind( 'isEnabled' ).to( command, 'isEnabled', ui, 'isVisible',
	( isCommandEnabled, isUIVisible ) => isCommandEnabled && isUIVisible );

    Using a custom callback allows processing the value before passing it to the target property:

    button.bind( 'isEnabled' ).to( command, 'value', value => value === 'heading1' );

    It is also possible to bind to the same property in an array of observables. To bind a button to multiple commands (also Observables) so that each and every one of them must be enabled for the button to become enabled, use the following code:

    button.bind( 'isEnabled' ).toMany( [ commandA, commandB, commandC ], 'isEnabled',
	( isAEnabled, isBEnabled, isCEnabled ) => isAEnabled && isBEnabled && isCEnabled );

    Parameters

    bindProperties : Array<'off' | 'on' | 'once' | 'listenTo' | 'stopListening' | 'fire' | 'delegate' | 'stopDelegating' | 'set' | 'bind' | 'unbind' | 'decorate' | 'render' | 'selection' | 'isFocused' | 'isSelecting' | 'isComposing' | 'domDocuments' | 'domConverter' | 'markedAttributes' | 'markedChildren' | 'markedTexts' | 'markToSync'>

    Observable properties that will be bound to other observable(s).

    Returns

    MultiBindChain

    The bind chain with the to() and toMany() methods.

  • inherited

    bind( bindProperty1, bindProperty2 ) → DualBindChain<K1, Renderer[ K1 ], K2, Renderer[ K2 ]>

    See source

    Binds observable properties to other objects implementing the Observable interface.

    Read more in the dedicated guide covering the topic of property bindings with some additional examples.

    Consider two objects: a button and an associated command (both Observable).

    A simple property binding could be as follows:

    button.bind( 'isEnabled' ).to( command, 'isEnabled' );

    or even shorter:

    button.bind( 'isEnabled' ).to( command );

    which works in the following way:

    • button.isEnabled instantly equals command.isEnabled,
    • whenever command.isEnabled changes, button.isEnabled will immediately reflect its value.

    Note: To release the binding, use unbind.

    You can also "rename" the property in the binding by specifying the new name in the to() chain:

    button.bind( 'isEnabled' ).to( command, 'isWorking' );

    It is possible to bind more than one property at a time to shorten the code:

    button.bind( 'isEnabled', 'value' ).to( command );

    which corresponds to:

    button.bind( 'isEnabled' ).to( command );
button.bind( 'value' ).to( command );

    The binding can include more than one observable, combining multiple data sources in a custom callback:

    button.bind( 'isEnabled' ).to( command, 'isEnabled', ui, 'isVisible',
	( isCommandEnabled, isUIVisible ) => isCommandEnabled && isUIVisible );

    Using a custom callback allows processing the value before passing it to the target property:

    button.bind( 'isEnabled' ).to( command, 'value', value => value === 'heading1' );

    It is also possible to bind to the same property in an array of observables. To bind a button to multiple commands (also Observables) so that each and every one of them must be enabled for the button to become enabled, use the following code:

    button.bind( 'isEnabled' ).toMany( [ commandA, commandB, commandC ], 'isEnabled',
	( isAEnabled, isBEnabled, isCEnabled ) => isAEnabled && isBEnabled && isCEnabled );

    Type parameters

    K1
    K2

    Parameters

    bindProperty1 : K1

    Observable property that will be bound to other observable(s).

    bindProperty2 : K2

    Observable property that will be bound to other observable(s).

    Returns

    DualBindChain<K1, Renderer[ K1 ], K2, Renderer[ K2 ]>

    The bind chain with the to() and toMany() methods.

  • inherited

    bind( bindProperty ) → SingleBindChain<K, Renderer[ K ]>

    See source

    Binds observable properties to other objects implementing the Observable interface.

    Read more in the dedicated guide covering the topic of property bindings with some additional examples.

    Consider two objects: a button and an associated command (both Observable).

    A simple property binding could be as follows:

    button.bind( 'isEnabled' ).to( command, 'isEnabled' );

    or even shorter:

    button.bind( 'isEnabled' ).to( command );

    which works in the following way:

    • button.isEnabled instantly equals command.isEnabled,
    • whenever command.isEnabled changes, button.isEnabled will immediately reflect its value.

    Note: To release the binding, use unbind.

    You can also "rename" the property in the binding by specifying the new name in the to() chain:

    button.bind( 'isEnabled' ).to( command, 'isWorking' );

    It is possible to bind more than one property at a time to shorten the code:

    button.bind( 'isEnabled', 'value' ).to( command );

    which corresponds to:

    button.bind( 'isEnabled' ).to( command );
button.bind( 'value' ).to( command );

    The binding can include more than one observable, combining multiple data sources in a custom callback:

    button.bind( 'isEnabled' ).to( command, 'isEnabled', ui, 'isVisible',
	( isCommandEnabled, isUIVisible ) => isCommandEnabled && isUIVisible );

    Using a custom callback allows processing the value before passing it to the target property:

    button.bind( 'isEnabled' ).to( command, 'value', value => value === 'heading1' );

    It is also possible to bind to the same property in an array of observables. To bind a button to multiple commands (also Observables) so that each and every one of them must be enabled for the button to become enabled, use the following code:

    button.bind( 'isEnabled' ).toMany( [ commandA, commandB, commandC ], 'isEnabled',
	( isAEnabled, isBEnabled, isCEnabled ) => isAEnabled && isBEnabled && isCEnabled );

    Type parameters

    K

    Parameters

    bindProperty : K

    Observable property that will be bound to other observable(s).

    Returns

    SingleBindChain<K, Renderer[ K ]>

    The bind chain with the to() and toMany() methods.

  • inherited

    decorate( methodName ) → void

    See source

    Turns the given methods of this object into event-based ones. This means that the new method will fire an event (named after the method) and the original action will be plugged as a listener to that event.

    Read more in the dedicated guide covering the topic of decorating methods with some additional examples.

    Decorating the method does not change its behavior (it only adds an event), but it allows to modify it later on by listening to the method's event.

    For example, to cancel the method execution the event can be stopped:

    class Foo extends ObservableMixin() {
	constructor() {
		super();
		this.decorate( 'method' );
	}

	method() {
		console.log( 'called!' );
	}
}

const foo = new Foo();
foo.on( 'method', ( evt ) => {
	evt.stop();
}, { priority: 'high' } );

foo.method(); // Nothing is logged.

    Note: The high priority listener has been used to execute this particular callback before the one which calls the original method (which uses the "normal" priority).

    It is also possible to change the returned value:

    foo.on( 'method', ( evt ) => {
	evt.return = 'Foo!';
} );

foo.method(); // -> 'Foo'

    Finally, it is possible to access and modify the arguments the method is called with:

    method( a, b ) {
	console.log( `${ a }, ${ b }`  );
}

// ...

foo.on( 'method', ( evt, args ) => {
	args[ 0 ] = 3;

	console.log( args[ 1 ] ); // -> 2
}, { priority: 'high' } );

foo.method( 1, 2 ); // -> '3, 2'

    Parameters

    methodName : 'off' | 'on' | 'once' | 'listenTo' | 'stopListening' | 'fire' | 'delegate' | 'stopDelegating' | 'set' | 'bind' | 'unbind' | 'decorate' | 'render' | 'selection' | 'isFocused' | 'isSelecting' | 'isComposing' | 'domDocuments' | 'domConverter' | 'markedAttributes' | 'markedChildren' | 'markedTexts' | 'markToSync'

    Name of the method to decorate.

    Returns

    void

  • inherited

    delegate( events ) → EmitterMixinDelegateChain

    See source

    Delegates selected events to another Emitter. For instance:

    emitterA.delegate( 'eventX' ).to( emitterB );
emitterA.delegate( 'eventX', 'eventY' ).to( emitterC );

    then eventX is delegated (fired by) emitterB and emitterC along with data:

    emitterA.fire( 'eventX', data );

    and eventY is delegated (fired by) emitterC along with data:

    emitterA.fire( 'eventY', data );

    Parameters

    events : Array<string>

    Event names that will be delegated to another emitter.

    Returns

    EmitterMixinDelegateChain

  • inherited

    fire( eventOrInfo, args ) → GetEventInfo<TEvent>[ 'return' ]

    See source

    Fires an event, executing all callbacks registered for it.

    The first parameter passed to callbacks is an EventInfo object, followed by the optional args provided in the fire() method call.

    Type parameters

    TEvent : extends BaseEvent

    The type describing the event. See BaseEvent.

    Parameters

    eventOrInfo : GetNameOrEventInfo<TEvent>

    The name of the event or EventInfo object if event is delegated.

    args : TEvent[ 'args' ]

    Additional arguments to be passed to the callbacks.

    Returns

    GetEventInfo<TEvent>[ 'return' ]

    By default the method returns undefined. However, the return value can be changed by listeners through modification of the evt.return's property (the event info is the first param of every callback).

  • inherited

    listenTo( emitter, event, callback, [ options ] ) → void

    See source

    Registers a callback function to be executed when an event is fired in a specific (emitter) object.

    Events can be grouped in namespaces using :. When namespaced event is fired, it additionally fires all callbacks for that namespace.

    // myEmitter.on( ... ) is a shorthand for myEmitter.listenTo( myEmitter, ... ).
myEmitter.on( 'myGroup', genericCallback );
myEmitter.on( 'myGroup:myEvent', specificCallback );

// genericCallback is fired.
myEmitter.fire( 'myGroup' );
// both genericCallback and specificCallback are fired.
myEmitter.fire( 'myGroup:myEvent' );
// genericCallback is fired even though there are no callbacks for "foo".
myEmitter.fire( 'myGroup:foo' );

    An event callback can stop the event and set the return value of the fire method.

    Type parameters

    TEvent : extends BaseEvent

    The type describing the event. See BaseEvent.

    Parameters

    emitter : Emitter

    The object that fires the event.

    event : TEvent[ 'name' ]

    The name of the event.

    callback : GetCallback<TEvent>

    The function to be called on event.

    [ options ] : GetCallbackOptions<TEvent>

    Additional options.

    Returns

    void

  • markToSync( type, node ) → void

    See source

    Marks a view node to be updated in the DOM by render().

    Note that only view nodes whose parents have corresponding DOM elements need to be marked to be synchronized.

    Parameters

    type : ChangeType

    Type of the change.

    node : Node

    ViewNode to be marked.

    Returns

    void

    Related:

  • inherited

    off( event, callback ) → void

    See source

    Stops executing the callback on the given event. Shorthand for this.stopListening( this, event, callback ).

    Parameters

    event : string

    The name of the event.

    callback : Function

    The function to stop being called.

    Returns

    void

  • inherited

    on( event, callback, [ options ] ) → void

    See source

    Registers a callback function to be executed when an event is fired.

    Shorthand for this.listenTo( this, event, callback, options ) (it makes the emitter listen on itself).

    Type parameters

    TEvent : extends BaseEvent

    The type descibing the event. See BaseEvent.

    Parameters

    event : TEvent[ 'name' ]

    The name of the event.

    callback : GetCallback<TEvent>

    The function to be called on event.

    [ options ] : GetCallbackOptions<TEvent>

    Additional options.

    Returns

    void

  • inherited

    once( event, callback, [ options ] ) → void

    See source

    Registers a callback function to be executed on the next time the event is fired only. This is similar to calling on followed by off in the callback.

    Type parameters

    TEvent : extends BaseEvent

    The type descibing the event. See BaseEvent.

    Parameters

    event : TEvent[ 'name' ]

    The name of the event.

    callback : GetCallback<TEvent>

    The function to be called on event.

    [ options ] : GetCallbackOptions<TEvent>

    Additional options.

    Returns

    void

  • render() → void

    See source

    Renders all buffered changes (markedAttributes, markedChildren and markedTexts) and the current view selection (if needed) to the DOM by applying a minimal set of changes to it.

    Renderer tries not to break the text composition (e.g. IME) and x-index of the selection, so it does as little as it is needed to update the DOM.

    Renderer also handles fillers. Especially, it checks if the inline filler is needed at the selection position and adds or removes it. To prevent breaking text composition inline filler will not be removed as long as the selection is in the text node which needed it at first.

    Returns

    void

  • inherited

    set( values ) → void

    See source

    Creates and sets the value of an observable properties of this object. Such a property becomes a part of the state and is observable.

    It accepts a single object literal containing key/value pairs with properties to be set.

    This method throws the observable-set-cannot-override error if the observable instance already has a property with the given property name. This prevents from mistakenly overriding existing properties and methods, but means that foo.set( 'bar', 1 ) may be slightly slower than foo.bar = 1.

    In TypeScript, those properties should be declared in class using declare keyword. In example:

    public declare myProp1: number;
public declare myProp2: string;

constructor() {
	this.set( {
		'myProp1: 2,
		'myProp2: 'foo'
	} );
}

    Parameters

    values : object

    An object with name=>value pairs.

    Returns

    void

  • inherited

    set( name, value ) → void

    See source

    Creates and sets the value of an observable property of this object. Such a property becomes a part of the state and is observable.

    This method throws the observable-set-cannot-override error if the observable instance already has a property with the given property name. This prevents from mistakenly overriding existing properties and methods, but means that foo.set( 'bar', 1 ) may be slightly slower than foo.bar = 1.

    In TypeScript, those properties should be declared in class using declare keyword. In example:

    public declare myProp: number;

constructor() {
	this.set( 'myProp', 2 );
}

    Type parameters

    K

    Parameters

    name : K

    The property's name.

    value : Renderer[ K ]

    The property's value.

    Returns

    void

  • inherited

    stopDelegating( [ event ], [ emitter ] ) → void

    See source

    Stops delegating events. It can be used at different levels:

    • To stop delegating all events.
    • To stop delegating a specific event to all emitters.
    • To stop delegating a specific event to a specific emitter.

    Parameters

    [ event ] : string

    The name of the event to stop delegating. If omitted, stops it all delegations.

    [ emitter ] : Emitter

    (requires event) The object to stop delegating a particular event to. If omitted, stops delegation of event to all emitters.

    Returns

    void

  • inherited

    stopListening( [ emitter ], [ event ], [ callback ] ) → void

    See source

    Stops listening for events. It can be used at different levels:

    • To stop listening to a specific callback.
    • To stop listening to a specific event.
    • To stop listening to all events fired by a specific object.
    • To stop listening to all events fired by all objects.

    Parameters

    [ emitter ] : Emitter

    The object to stop listening to. If omitted, stops it for all objects.

    [ event ] : string

    (Requires the emitter) The name of the event to stop listening to. If omitted, stops it for all events from emitter.

    [ callback ] : Function

    (Requires the event) The function to be removed from the call list for the given event.

    Returns

    void

  • inherited

    unbind( unbindProperties ) → void

    See source

    Removes the binding created with bind.

    // Removes the binding for the 'a' property.
A.unbind( 'a' );

// Removes bindings for all properties.
A.unbind();

    Parameters

    unbindProperties : Array<'off' | 'on' | 'once' | 'listenTo' | 'stopListening' | 'fire' | 'delegate' | 'stopDelegating' | 'set' | 'bind' | 'unbind' | 'decorate' | 'render' | 'selection' | 'isFocused' | 'isSelecting' | 'isComposing' | 'domDocuments' | 'domConverter' | 'markedAttributes' | 'markedChildren' | 'markedTexts' | 'markToSync'>

    Observable properties to be unbound. All the bindings will be released if no properties are provided.

    Returns

    void

  • private

    _diffNodeLists( actualDomChildren, expectedDomChildren ) → Array<DiffResult>

    See source

    Shorthand for diffing two arrays or node lists of DOM nodes.

    Parameters

    actualDomChildren : Array<Node> | NodeList

    Actual DOM children

    expectedDomChildren : Array<Node> | NodeList

    Expected DOM children.

    Returns

    Array<DiffResult>

    The list of actions based on the diff function.

  • private

    _domSelectionNeedsUpdate( domSelection ) → boolean

    See source

    Checks whether a given DOM selection needs to be updated.

    Parameters

    domSelection : Selection

    The DOM selection to check.

    Returns

    boolean

  • private

    _fakeSelectionNeedsUpdate( domEditable ) → boolean

    See source

    Checks whether the fake selection needs to be updated.

    Parameters

    domEditable : HTMLElement

    A valid DOM editable where a new fake selection container should be added.

    Returns

    boolean

  • private

    _findUpdateActions( actions, actualDom, expectedDom, comparator ) → Array<DiffResult | 'update'>

    See source

    Finds DOM nodes that were replaced with the similar nodes (same tag name) in the view. All nodes are compared within one insert/delete action group, for example:

    Actual DOM:		<p><b>Foo</b>Bar<i>Baz</i><b>Bax</b></p>
Expected DOM:	<p>Bar<b>123</b><i>Baz</i><b>456</b></p>
Input actions:	[ insert, insert, delete, delete, equal, insert, delete ]
Output actions:	[ insert, replace, delete, equal, replace ]

    Parameters

    actions : Array<DiffResult>

    Actions array which is a result of the diff function.

    actualDom : Array<Node> | NodeList

    Actual DOM children

    expectedDom : Array<Node>

    Expected DOM children.

    comparator : ( a: Node, b: Node ) => boolean

    A comparator function that should return true if the given node should be reused (either by the update of a text node data or an element children list for similar elements).

    Returns

    Array<DiffResult | 'update'>

    Actions array modified with the update actions.

  • private

    _getInlineFillerPosition() → Position

    See source

    Gets the position of the inline filler based on the current selection. Here, we assume that we know that the filler is needed and is at the selection position, and, since it is needed, it is somewhere at the selection position.

    Note: The filler position cannot be restored based on the filler's DOM text node, because when this method is called (before rendering), the bindings will often be broken. View-to-DOM bindings are only dependable after rendering.

    Returns

    Position

  • private

    _isSelectionInInlineFiller() → boolean

    See source

    Returns true if the selection has not left the inline filler's text node. If it is true, it means that the filler had been added for a reason and the selection did not leave the filler's text node. For example, the user can be in the middle of a composition so it should not be touched.

    Returns

    boolean

    true if the inline filler and selection are in the same place.

  • private

    _markDescendantTextToSync( viewNode ) → void

    See source

    Marks text nodes to be synchronized.

    If a text node is passed, it will be marked. If an element is passed, all descendant text nodes inside it will be marked.

    Parameters

    viewNode : undefined | Node

    View node to sync.

    Returns

    void

  • private

    _needsInlineFillerAtSelection() → boolean

    See source

    Checks if the inline filler should be added.

    Returns

    boolean

    true if the inline filler should be added.

  • private

    _removeDomSelection() → void

    See source

    Removes the DOM selection.

    Returns

    void

  • private

    _removeFakeSelection() → void

    See source

    Removes the fake selection.

    Returns

    void

  • private

    _removeInlineFiller() → void

    See source

    Removes the inline filler.

    Returns

    void

  • private

    _updateAttrs( viewElement ) → void

    See source

    Checks if attribute list needs to be updated and possibly updates it.

    Parameters

    viewElement : Element

    The view element to update.

    Returns

    void

  • private

    _updateChildren( viewElement, options = { options.inlineFillerPosition } ) → void

    See source

    Checks if elements child list needs to be updated and possibly updates it.

    Note that on Android, to reduce the risk of composition breaks, it tries to update data of an existing child text nodes instead of replacing them completely.

    Parameters

    viewElement : Element

    View element to update.

    options : object
    Properties
    options.inlineFillerPosition : null | Position

    The position where the inline filler should be rendered.

    Returns

    void

  • private

    _updateChildrenMappings( viewElement ) → void

    See source

    Updates mappings of view element's children.

    Children that were replaced in the view structure by similar elements (same tag name) are treated as 'replaced'. This means that their mappings can be updated so the new view elements are mapped to the existing DOM elements. Thanks to that these elements do not need to be re-rendered completely.

    Parameters

    viewElement : Element

    The view element whose children mappings will be updated.

    Returns

    void

  • private

    _updateDomSelection( domEditable ) → void

    See source

    Updates the DOM selection.

    Parameters

    domEditable : HTMLElement

    A valid DOM editable where the DOM selection should be rendered.

    Returns

    void

  • private

    _updateElementMappings( viewElement, domElement ) → void

    See source

    Updates mappings of a given view element.

    Parameters

    viewElement : Element

    The view element whose mappings will be updated.

    domElement : HTMLElement

    The DOM element representing the given view element.

    Returns

    void

  • private

    _updateFakeSelection( domEditable ) → void

    See source

    Updates the fake selection.

    Parameters

    domEditable : HTMLElement

    A valid DOM editable where the fake selection container should be added.

    Returns

    void

  • private

    _updateFocus() → void

    See source

    Checks if focus needs to be updated and possibly updates it.

    Returns

    void

  • private

    _updateSelection() → void

    See source

    Checks if the selection needs to be updated and possibly updates it.

    Returns

    void

  • private

    _updateText( viewText, options = { [options.inlineFillerPosition] } ) → void

    See source

    Checks if text needs to be updated and possibly updates it.

    Parameters

    viewText : Text

    View text to update.

    options : object
    Properties
    [ options.inlineFillerPosition ] : null | Position

    The position where the inline filler should be rendered.

    Returns

    void

  • private

    _updateTextNode( domText, expectedText ) → void

    See source

    Checks if text needs to be updated and possibly updates it by removing and inserting only parts of the data from the existing text node to reduce impact on the IME composition.

    Parameters

    domText : Text

    DOM text node to update.

    expectedText : string

    The expected data of a text node.

    Returns

    void

  • private

    _updateTextNodeInternal( domText, expectedText ) → void

    See source

    Part of the _updateTextNode method extracted for easier testing.

    Parameters

    domText : Text
    expectedText : string

    Returns

    void

Events

  • change:isComposing( eventInfo, name, value, oldValue )

    See source

    Fired when the isComposing property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isComposing).

    value : boolean

    New value of the isComposing property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isComposing property with given key or null, if property was not set before.

  • change:isFocused( eventInfo, name, value, oldValue )

    See source

    Fired when the isFocused property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isFocused).

    value : boolean

    New value of the isFocused property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isFocused property with given key or null, if property was not set before.

  • change:isSelecting( eventInfo, name, value, oldValue )

    See source

    Fired when the isSelecting property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isSelecting).

    value : boolean

    New value of the isSelecting property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isSelecting property with given key or null, if property was not set before.

  • inherited

    change:{property}( eventInfo, name, value, oldValue )

    See source

    Fired when a property changed value.

    observable.set( 'prop', 1 );

observable.on<ObservableChangeEvent<number>>( 'change:prop', ( evt, propertyName, newValue, oldValue ) => {
	console.log( `${ propertyName } has changed from ${ oldValue } to ${ newValue }` );
} );

observable.prop = 2; // -> 'prop has changed from 1 to 2'

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    The property name.

    value : TValue

    The new property value.

    oldValue : TValue

    The previous property value.

  • set:isComposing( eventInfo, name, value, oldValue )

    See source

    Fired when the isComposing property is going to be set but is not set yet (before the change event is fired).

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isComposing).

    value : boolean

    New value of the isComposing property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isComposing property with given key or null, if property was not set before.

  • set:isFocused( eventInfo, name, value, oldValue )

    See source

    Fired when the isFocused property is going to be set but is not set yet (before the change event is fired).

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isFocused).

    value : boolean

    New value of the isFocused property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isFocused property with given key or null, if property was not set before.

  • set:isSelecting( eventInfo, name, value, oldValue )

    See source

    Fired when the isSelecting property is going to be set but is not set yet (before the change event is fired).

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isSelecting).

    value : boolean

    New value of the isSelecting property with given key or null, if operation should remove property.

    oldValue : boolean

    Old value of the isSelecting property with given key or null, if property was not set before.

  • inherited

    set:{property}( eventInfo, name, value, oldValue )

    See source

    Fired when a property value is going to be set but is not set yet (before the change event is fired).

    You can control the final value of the property by using the event's return property.

    observable.set( 'prop', 1 );

observable.on<ObservableSetEvent<number>>( 'set:prop', ( evt, propertyName, newValue, oldValue ) => {
	console.log( `Value is going to be changed from ${ oldValue } to ${ newValue }` );
	console.log( `Current property value is ${ observable[ propertyName ] }` );

	// Let's override the value.
	evt.return = 3;
} );

observable.on<ObservableChangeEvent<number>>( 'change:prop', ( evt, propertyName, newValue, oldValue ) => {
	console.log( `Value has changed from ${ oldValue } to ${ newValue }` );
} );

observable.prop = 2; // -> 'Value is going to be changed from 1 to 2'
                     // -> 'Current property value is 1'
                     // -> 'Value has changed from 1 to 3'

    Note: The event is fired even when the new value is the same as the old value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    The property name.

    value : TValue

    The new property value.

    oldValue : TValue

    The previous property value.