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Class

Document (engine/model)

@ckeditor/ckeditor5-engine/src/model/document

class
See source

Data model's document. It contains the model's structure, its selection and the history of changes.

Read more about working with the model in introduction to the the editing engine's architecture.

Usually, the document contains just one root element, so you can retrieve it by just calling getRoot without specifying its name:

model.document.getRoot(); // -> returns the main root

However, the document may contain multiple roots – e.g. when the editor has multiple editable areas (e.g. a title and a body of a message).

Filtering

Properties

Methods

  • constructor()

    Creates an empty document instance with no roots (other than the graveyard root).

    See source

  • createRoot( [ elementName ], [ rootName ] ) → RootElement

    Creates a new root.

    See source

    Parameters

    [ elementName ] : String

    The element name. Defaults to '$root' which also has some basic schema defined ($blocks are allowed inside the $root). Make sure to define a proper schema if you use a different name.

    Defaults to '$root'

    [ rootName ] : String

    A unique root name.

    Defaults to 'main'

    Returns

    RootElement

    The created root.

  • delegate( events ) → EmitterMixinDelegateChain

    mixed

    Delegates selected events to another Emitter. For instance:

    See source
    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 : String

    Event names that will be delegated to another emitter.

    Returns

    EmitterMixinDelegateChain

  • destroy()

    Removes all event listeners set by the document instance.

    See source

  • fire( eventOrInfo, [ args ] ) → *

    mixed

    Fires an event, executing all callbacks registered for it.

    See source

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

    Parameters

    eventOrInfo : String | EventInfo

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

    [ args ] : *

    Additional arguments to be passed to the callbacks.

    Returns

    *

    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).

  • getRoot( [ name ] ) → RootElement | null

    Returns a root by its name.

    See source

    Parameters

    [ name ] : String

    A unique root name.

    Defaults to 'main'

    Returns

    RootElement | null

    The root registered under a given name or null when there is no root with the given name.

  • getRootNames() → Array.<String>

    Returns an array with names of all roots (without the graveyard) added to the document.

    See source

    Returns

    Array.<String>

    Roots names.

  • listenTo( emitter, event, callback, [ options ] = { [options.priority] } )

    mixed

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

    See source

    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.

    Parameters

    emitter : Emitter

    The object that fires the event.

    event : String

    The name of the event.

    callback : function

    The function to be called on event.

    [ options ] : Object

    Additional options.

    Properties
    [ options.priority ] : PriorityString | Number

    The priority of this event callback. The higher the priority value the sooner the callback will be fired. Events having the same priority are called in the order they were added.

    Defaults to 'normal'

    Defaults to {}

  • off( event, callback )

    mixed

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

    See source

    Parameters

    event : String

    The name of the event.

    callback : function

    The function to stop being called.

  • on( event, callback, [ options ] = { [options.priority] } )

    mixed

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

    See source

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

    Parameters

    event : String

    The name of the event.

    callback : function

    The function to be called on event.

    [ options ] : Object

    Additional options.

    Properties
    [ options.priority ] : PriorityString | Number

    The priority of this event callback. The higher the priority value the sooner the callback will be fired. Events having the same priority are called in the order they were added.

    Defaults to 'normal'

    Defaults to {}

  • once( event, callback, [ options ] = { [options.priority] } )

    mixed

    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.

    See source

    Parameters

    event : String

    The name of the event.

    callback : function

    The function to be called on event.

    [ options ] : Object

    Additional options.

    Properties
    [ options.priority ] : PriorityString | Number

    The priority of this event callback. The higher the priority value the sooner the callback will be fired. Events having the same priority are called in the order they were added.

    Defaults to 'normal'

    Defaults to {}

  • registerPostFixer( postFixer )

    Used to register a post-fixer callback. A post-fixer mechanism guarantees that the features will operate on a correct model state.

    See source

    An execution of a feature may lead to an incorrect document tree state. The callbacks are used to fix the document tree after it has changed. Post-fixers are fired just after all changes from the outermost change block were applied but before the change event is fired. If a post-fixer callback made a change, it should return true. When this happens, all post-fixers are fired again to check if something else should not be fixed in the new document tree state.

    As a parameter, a post-fixer callback receives a writer instance connected with the executed changes block. Thanks to that, all changes done by the callback will be added to the same batch (and undo step) as the original changes. This makes post-fixer changes transparent for the user.

    An example of a post-fixer is a callback that checks if all the data were removed from the editor. If so, the callback should add an empty paragraph so that the editor is never empty:

    document.registerPostFixer( writer => {
	const changes = document.differ.getChanges();

	// Check if the changes lead to an empty root in the editor.
	for ( const entry of changes ) {
		if ( entry.type == 'remove' && entry.position.root.isEmpty ) {
			writer.insertElement( 'paragraph', entry.position.root, 0 );

			// It is fine to return early, even if multiple roots would need to be fixed.
			// All post-fixers will be fired again, so if there are more empty roots, those will be fixed, too.
			return true;
		}
	}
} );

    Parameters

    postFixer : function

  • stopDelegating( [ event ], [ emitter ] )

    mixed

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

    See source
    • 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.

  • stopListening( [ emitter ], [ event ], [ callback ] )

    mixed

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

    See source
    • 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.

  • toJSON() → Object

    A custom toJSON() method to solve child-parent circular dependencies.

    See source

    Returns

    Object

    A clone of this object with the document property changed to a string.

  • _addEventListener( event, callback, [ options ] = { [options.priority] } )

    protected mixed

    Adds callback to emitter for given event.

    See source

    Parameters

    event : String

    The name of the event.

    callback : function

    The function to be called on event.

    [ options ] : Object

    Additional options.

    Properties
    [ options.priority ] : PriorityString | Number

    The priority of this event callback. The higher the priority value the sooner the callback will be fired. Events having the same priority are called in the order they were added.

    Defaults to 'normal'

    Defaults to {}

  • _getDefaultRange() → Range

    protected

    Returns the default range for this selection. The default range is a collapsed range that starts and ends at the beginning of this selection's document default root.

    See source

    Returns

    Range

  • _getDefaultRoot() → RootElement

    protected

    Returns the default root for this document which is either the first root that was added to the document using createRoot or the graveyard root if no other roots were created.

    See source

    Returns

    RootElement

    The default root for this document.

  • _handleChangeBlock( writer )

    protected

    Check if there were any changes done on document, and if so, call post-fixers, fire change event for features and conversion and then reset the differ. Fire change:data event when at least one operation or buffered marker changes the data.

    See source

    Parameters

    writer : Writer

    The writer on which post-fixers will be called.

    Fires

  • _hasDocumentChangedFromTheLastChangeBlock() → Boolean

    protected

    Returns whether there is a buffered change or if the selection has changed from the last enqueueChange() block or change() block.

    See source

    Returns

    Boolean

    Returns true if document has changed from the last change() or enqueueChange() block.

  • _removeEventListener( event, callback )

    protected mixed

    Removes callback from emitter for given event.

    See source

    Parameters

    event : String

    The name of the event.

    callback : function

    The function to stop being called.

  • _callPostFixers( writer )

    private

    Performs post-fixer loops. Executes post-fixer callbacks as long as none of them has done any changes to the model.

    See source

    Parameters

    writer : Writer

    The writer on which post-fixer callbacks will be called.

  • _validateSelectionRange( range ) → Boolean

    private

    Checks whether a given range is a valid range for the document's selection.

    See source

    Parameters

    range : Range

    A range to check.

    Returns

    Boolean

    true if range is valid, false otherwise.

Events

  • change( eventInfo, batch )

    Fired after each enqueueChange() block or the outermost change() block was executed and the document was changed during that block's execution.

    See source

    The changes which this event will cover include:

    • document structure changes,
    • selection changes,
    • marker changes.

    If you want to be notified about all these changes, then simply listen to this event like this:

    model.document.on( 'change', () => {
	console.log( 'The document has changed!' );
} );

    If, however, you only want to be notified about the data changes, then use the change:data event, which is fired for document structure changes and marker changes (which affects the data).

    model.document.on( 'change:data', () => {
	console.log( 'The data has changed!' );
} );

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    batch : Batch

    The batch that was used in the executed changes block.

  • change:data( eventInfo, batch )

    It is a narrower version of the event-change event. It is fired for changes which affect the editor data. This is:

    See source
    • document structure changes,
    • marker changes (which affects the data).

    If you want to be notified about the data changes, then listen to this event:

    model.document.on( 'change:data', () => {
	console.log( 'The data has changed!' );
} );

    If you would like to listen to all document changes, then check out the change event.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    batch : Batch

    The batch that was used in the executed changes block.