ModelDocument

The model differ object. Its role is to buffer changes done on the model document and then calculate a diff of those changes.

The graveyard tree root. A document always has a graveyard root that stores removed nodes.

The document's history.

Defines whether the document is in a read-only mode.

The user should not be able to change the data of a document that is read-only.

The model that the document is a part of.

A list of roots that are owned and managed by this document. Use createRoot, getRoot and getRootNames to manipulate it.

The selection in this document.

The document version. Every applied operation increases the version number. It is used to ensure that operations are applied on a proper document version.

This property is equal to model.Document#history#version.

If the base version does not match the document version, a model-document-applyoperation-wrong-version error is thrown.

Parameters

version : number

A flag that indicates whether the selection has changed since last change block.

Post-fixer callbacks registered to the model document.

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

Parameters

model : Model

Creates a new root.

Note: do not use this method after the editor has been initialized! If you want to dynamically add a root, use model.Writer#addRoot instead.

Parameters

elementName : string

The element name. Defaults to '$root' which also has some basic schema defined (e.g. $block elements 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

ModelRootElement

The created root.

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

Removes all event listeners set by the document instance.

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 a root by its name.

Detached roots are returned by this method. This is to be able to operate on the detached root (for example, to be able to create a position inside such a root for undo feature purposes).

Parameters

name : string

The root name of the root to return.

Defaults to 'main'

Returns

null | ModelRootElement

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

Returns an array with names of all roots added to the document (except the graveyard root).

Detached roots are not returned by this method by default. This is to make sure that all features or algorithms that operate on the document data know which roots are still a part of the document and should be processed.

Parameters

includeDetached : boolean

Specified whether detached roots should be returned as well.

Defaults to false

Returns

Array<string>

Returns an array with all roots added to the document (except the graveyard root).

Detached roots are not returned by this method by default. This is to make sure that all features or algorithms that operate on the document data know which roots are still a part of the document and should be processed.

Parameters

includeDetached : boolean

Specified whether detached roots should be returned as well.

Defaults to false

Returns

Array<ModelRootElement>

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

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

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;
		}
	}

	return false;
} );

Parameters

postFixer : ModelPostFixer

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

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

Returns

unknown

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

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.

Returns

ModelRange

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.

Parameters

writer : ModelWriter

The writer on which post-fixers will be called.

Returns

void

Fires

• change
• change:data

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

Parameters

range : ModelRange

A range to check.

Returns

boolean

true if range is valid, false otherwise.

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.

Returns

ModelRootElement

The default root for this document.

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

Returns

boolean

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

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

Parameters

writer : ModelWriter

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

Returns

void

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

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 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.

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

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 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.