EditorUI

A helper that manages the content of an aria-live regions used by editor features to announce status changes to screen readers.

An instance of the ComponentFactory, a registry used by plugins to register factories of specific UI components.

The editor that the UI belongs to.

The main (outermost) DOM element of the editor UI.

For example, in ClassicEditor it is a <div> which wraps the editable element and the toolbar. In InlineEditor it is the editable element itself (as there is no other wrapper). However, in DecoupledEditor it is set to null because this editor does not come with a single "main" HTML element (its editable element and toolbar are separate).

This property can be understood as a shorthand for retrieving the element that a specific editor integration considers to be its main DOM element.

A helper that enables the "evaluation badge" feature in the editor.

Stores the information about the editor UI focus and propagates it so various plugins and components are unified as a focus group.

Indicates the UI is ready. Set true after event-ready event is fired.

Defaults to false

A helper that enables the "powered by" feature in the editor and renders a link to the project's webpage.

Manages the tooltips displayed on mouseover and focus across the UI.

Stores viewport offsets from every direction.

Viewport offset can be used to constrain balloons or other UI elements into an element smaller than the viewport. This can be useful if there are any other absolutely positioned elements that may interfere with editor UI.

Example editor.ui.viewportOffset returns:

{
	top: 50,
	right: 50,
	bottom: 50,
	left: 50,
	visualTop: 50
}

This property can be overriden after editor already being initialized:

editor.ui.viewportOffset = {
	top: 100,
	right: 0,
	bottom: 0,
	left: 0
};

The DOM emitter instance used for visual viewport watching.

Stores all editable elements used by the editor instance.

All additional menu bar items, groups or menus that have their default location defined.

All available & focusable toolbars.

The last focused element to which focus should return on Esc press.

Creates an instance of the editor UI class.

Parameters

editor : Editor

The editor instance.

Adds a toolbar to the editor UI. Used primarily to maintain the accessibility of the UI.

Focusable toolbars can be accessed (focused) by users by pressing the Alt + F10 keystroke. Successive keystroke presses navigate over available toolbars.

Parameters

toolbarView : ToolbarView

A instance of the toolbar to be registered.

options : FocusableToolbarOptions

Defaults to {}

Returns

void

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' | 'set' | 'bind' | 'unbind' | 'decorate' | 'stopListening' | 'on' | 'once' | 'listenTo' | 'fire' | 'delegate' | 'stopDelegating' | 'element' | 'view' | 'viewportOffset' | 'destroy' | 'update' | 'focusTracker' | 'poweredBy' | 'componentFactory' | 'editor' | 'tooltipManager' | 'evaluationBadge' | 'ariaLiveAnnouncer' | 'isReady' | 'setEditableElement' | 'removeEditableElement' | 'getEditableElement' | 'getEditableElementsNames' | 'addToolbar' | 'extendMenuBar' | 'initMenuBar'>

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

Returns

ObservableMultiBindChain

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

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

ObservableDualBindChain<K1, EditorUI[ K1 ], K2, EditorUI[ K2 ]>

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

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

ObservableSingleBindChain<K, EditorUI[ K ]>

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

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' | 'set' | 'bind' | 'unbind' | 'decorate' | 'stopListening' | 'on' | 'once' | 'listenTo' | 'fire' | 'delegate' | 'stopDelegating' | 'element' | 'view' | 'viewportOffset' | 'destroy' | 'update' | 'focusTracker' | 'poweredBy' | 'componentFactory' | 'editor' | 'tooltipManager' | 'evaluationBadge' | 'ariaLiveAnnouncer' | 'isReady' | 'setEditableElement' | 'removeEditableElement' | 'getEditableElement' | 'getEditableElementsNames' | 'addToolbar' | 'extendMenuBar' | 'initMenuBar'

Name of the method to decorate.

Returns

void

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

Destroys the UI.

Returns

void

Registers an extra menu bar element, which could be a single item, a group of items, or a menu containing groups.

// Register a new menu bar item.
editor.ui.extendMenuBar( {
  item: 'menuBar:customFunctionButton',
  position: 'after:menuBar:bold'
} );

// Register a new menu bar group.
editor.ui.extendMenuBar( {
  group: {
    groupId: 'customGroup',
    items: [
      'menuBar:customFunctionButton'
    ]
  },
  position: 'start:help'
} );

// Register a new menu bar menu.
editor.ui.extendMenuBar( {
  menu: {
    menuId: 'customMenu',
    label: 'customMenu',
    groups: [
      {
        groupId: 'customGroup',
        items: [
          'menuBar:customFunctionButton'
        ]
      }
    ]
  },
  position: 'after:help'
} );

Parameters

config : MenuBarConfigAddedItem | MenuBarConfigAddedGroup | MenuBarConfigAddedMenu

Returns

void

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).

Returns the editable editor element with the given name or null if editable does not exist.

Parameters

rootName : string

The editable name.

Defaults to 'main'

Returns

undefined | HTMLElement

Returns array of names of all editor editable elements.

Returns

IterableIterator<string>

Initializes menu bar.

Parameters

menuBarView : MenuBarView

Returns

void

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

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

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

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

Removes the editable from the editor UI. Removes all handlers added by setEditableElement.

Parameters

rootName : string

The name of the editable element to remove.

Returns

void

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

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 : EditorUI[ K ]

The property's value.

Returns

void

Stores the native DOM editable element used by the editor under a unique name.

Also, registers the element in the editor to maintain the accessibility of the UI. When the user is editing text in a focusable editable area, they can use the Alt + F10 keystroke to navigate over editor toolbars. See addToolbar.

Parameters

rootName : string

The unique name of the editable element.

domElement : HTMLElement

The native DOM editable element.

Returns

void

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

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

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' | 'set' | 'bind' | 'unbind' | 'decorate' | 'stopListening' | 'on' | 'once' | 'listenTo' | 'fire' | 'delegate' | 'stopDelegating' | 'element' | 'view' | 'viewportOffset' | 'destroy' | 'update' | 'focusTracker' | 'poweredBy' | 'componentFactory' | 'editor' | 'tooltipManager' | 'evaluationBadge' | 'ariaLiveAnnouncer' | 'isReady' | 'setEditableElement' | 'removeEditableElement' | 'getEditableElement' | 'getEditableElementsNames' | 'addToolbar' | 'extendMenuBar' | 'initMenuBar'>

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

Returns

void

Fires the update event.

This method should be called when the editor UI (e.g. positions of its balloons) needs to be updated due to some environmental change which CKEditor 5 is not aware of (e.g. resize of a container in which it is used).

Returns

void

Ensures that the focus tracker is aware of all views' DOM elements in the body collection.

Returns

void

Focuses a focusable toolbar candidate using its definition.

Parameters

candidateToolbarDefinition : FocusableToolbarDefinition

A definition of the toolbar to focus.

Returns

boolean

true when the toolbar candidate was focused. false otherwise.

Returns a definition of the toolbar that is currently visible and focused (one of its children has focus).

null is returned when no toolbar is currently focused.

Returns

null | FocusableToolbarDefinition

Returns definitions of toolbars that could potentially be focused, sorted by their importance for the user.

Focusable toolbars candidates are either:

• already visible,
• have beforeFocus() set in their definition that suggests that they might show up when called. Keep in mind that determining whether a toolbar will show up (and become focusable) is impossible at this stage because it depends on its implementation, that in turn depends on the editing context (selection).

Note: Contextual toolbars take precedence over regular toolbars.

Returns

Array<FocusableToolbarDefinition>

Calculate the viewport top offset according to the visible part of it (visual viewport).

Parameters

viewportOffset : object

Properties

[ viewportOffset.top ] : number

Returns

number

Provides an integration between viewportOffset and scrollViewportToShowTarget. It allows the UI-agnostic engine method to consider user-configured viewport offsets specific for the integration.

Parameters

evt : EventInfo<'scrollToTheSelection'>

The scrollToTheSelection event info.

data : ViewScrollToTheSelectionEventData

The payload carried by the scrollToTheSelection event.

Returns

void

Starts listening for Alt + F10 and Esc keystrokes in the context of focusable editable elements and toolbars to allow users navigate across the UI.

Returns

void

Set initial viewport offset and setup visualTop augmentation.

Parameters

viewportOffsetConfig : ViewportOffsetConfig

Returns

void

Listen to visual viewport changes and update the viewportOffset with the visualTop property according to the visible part of it (visual viewport).

Returns

void

Returns viewport offsets object:

{
	top: Number,
	right: Number,
	bottom: Number,
	left: Number
}

Only top property is currently supported.

Returns

ViewportOffsetConfig

Saves last focused element that doen not belong to editing view to restore focus on Esc.

Returns

void

Fired when the viewportOffset property changed value.

Parameters

eventInfo : EventInfo

An object containing information about the fired event.

name : string

Name of the changed property (viewportOffset).

value : ViewportOffset

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

oldValue : ViewportOffset

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

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.

Fired when the editor UI is ready.

Fired before event-ready.

Parameters

eventInfo : EventInfo

An object containing information about the fired event.

Fired when the viewportOffset 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 (viewportOffset).

value : ViewportOffset

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

oldValue : ViewportOffset

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

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.

Fired whenever the UI (all related components) should be refreshed.

Note:: The event is fired after each event-layoutChanged. It can also be fired manually via the update method.

Parameters

eventInfo : EventInfo

An object containing information about the fired event.