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Class

Resizer (widget/widgetresize)

@ckeditor/ckeditor5-widget/src/widgetresize/resizer

class
See source

Represents a resizer for a single resizable object.

Filtering

Properties

  • readonly

    _domResizerWrapper : null | HTMLElement

    See source

    DOM container of the entire resize UI.

    Note that this property will have a value only after the element bound with the resizer is rendered (otherwise null).

  • observable

    isEnabled : boolean

    See source

    Flag that indicates whether resizer can be used.

  • observable

    isSelected : boolean

    See source

    Flag that indicates that resizer is currently focused.

  • readonly observable

    isVisible : boolean

    See source

    Flag that indicates whether resizer is rendered (visible on the screen).

  • readonly

    state : ResizeState

    See source

    Stores the state of the resizable host geometry, such as the original width, the currently proposed height, etc.

    Note that a new state is created for each resize transaction.

  • private

    _initialViewWidth : undefined | string

    See source

    The width of the resized viewElement before the resizing started.

  • private

    _options : ResizerOptions

    See source

    Options passed to the constructor.

  • private

    _sizeView : SizeView

    See source

    A view displaying the proposed new element size during the resizing.

  • private

    _state : ResizeState

    See source

    Stores the state of the resizable host geometry, such as the original width, the currently proposed height, etc.

    Note that a new state is created for each resize transaction.

  • private

    _viewResizerWrapper : null | Element

    See source

    A wrapper that is controlled by the resizer. This is usually a widget element.

Methods

  • constructor( options )

    See source

    Parameters

    options : ResizerOptions

    Resizer options.

  • attach() → void

    See source

    Attaches the resizer to the DOM.

    Returns

    void

  • begin( domResizeHandle ) → void

    See source

    Starts the resizing process.

    Creates a new state for the current process.

    Parameters

    domResizeHandle : HTMLElement

    Clicked handle.

    Returns

    void

    Fires

  • inherited

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

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

  • 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' | 'cancel' | 'destroy' | 'isVisible' | 'isEnabled' | 'show' | 'hide' | 'state' | 'begin' | 'isSelected' | 'attach' | 'updateSize' | 'commit' | 'redraw' | 'containsHandle'>

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

    Returns

    MultiBindChain

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

  • inherited

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

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

  • cancel() → void

    See source

    Cancels and rejects the proposed resize dimensions, hiding the UI.

    Returns

    void

    Fires

  • commit() → void

    See source

    Applies the geometry proposed with the resizer.

    Returns

    void

    Fires

  • containsHandle( domElement ) → boolean

    See source

    Parameters

    domElement : HTMLElement

    Returns

    boolean

  • 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' | 'cancel' | 'destroy' | 'isVisible' | 'isEnabled' | 'show' | 'hide' | 'state' | 'begin' | 'isSelected' | 'attach' | 'updateSize' | 'commit' | 'redraw' | 'containsHandle'

    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

  • destroy() → void

    See source

    Destroys the resizer.

    Returns

    void

  • 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).

  • hide() → void

    See source

    Hides resizer in the UI.

    Returns

    void

  • 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

  • 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

  • redraw( [ handleHostRect ] ) → void

    See source

    Redraws the resizer.

    Parameters

    [ handleHostRect ] : Rect

    Handle host rectangle might be given to improve performance.

    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 : Resizer[ K ]

    The property's value.

    Returns

    void

  • show() → void

    See source

    Makes resizer visible in the UI.

    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' | 'cancel' | 'destroy' | 'isVisible' | 'isEnabled' | 'show' | 'hide' | 'state' | 'begin' | 'isSelected' | 'attach' | 'updateSize' | 'commit' | 'redraw' | 'containsHandle'>

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

    Returns

    void

  • updateSize( domEventData ) → void

    See source

    Updates the proposed size based on domEventData.

    Parameters

    domEventData : MouseEvent

    Returns

    void

    Fires

  • private

    _appendHandles( domElement ) → void

    See source

    Renders the resize handles in the DOM.

    Parameters

    domElement : HTMLElement

    The resizer wrapper.

    Returns

    void

  • private

    _appendSizeUI( domElement ) → void

    See source

    Sets up the _sizeView property and adds it to the passed domElement.

    Parameters

    domElement : HTMLElement

    Returns

    void

  • private

    _cleanup() → void

    See source

    Cleans up the context state.

    Returns

    void

  • private

    _getHandleHost() → HTMLElement

    See source

    Obtains the handle host.

    Handle host is an object that the handles are aligned to.

    Handle host will not always be an entire widget itself. Take an image as an example. The image widget contains an image and a caption. Only the image should be surrounded with handles.

    Returns

    HTMLElement

  • private

    _getResizeHost() → HTMLElement

    See source

    Obtains the resize host.

    Resize host is an object that receives dimensions which are the result of resizing.

    Returns

    HTMLElement

  • private

    _proposeNewSize( domEventData ) → object

    See source

    Calculates the proposed size as the resize handles are dragged.

    Parameters

    domEventData : MouseEvent

    Event data that caused the size update request. It should be used to calculate the proposed size.

    Returns

    object

Static methods

  • static

    isResizeHandle( domElement ) → boolean

    See source

    Parameters

    domElement : HTMLElement

    Returns

    boolean

Events

  • begin( eventInfo, <anonymous> )

    See source

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    <anonymous> : Parameters<TObservable[ TName ]>

  • cancel( eventInfo, <anonymous> )

    See source

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    <anonymous> : Parameters<TObservable[ TName ]>

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

    See source

    Fired when the isEnabled property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isEnabled).

    value : boolean

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

    oldValue : boolean

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

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

    See source

    Fired when the isSelected property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isSelected).

    value : boolean

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

    oldValue : boolean

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

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

    See source

    Fired when the isVisible property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (isVisible).

    value : boolean

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

    oldValue : boolean

    Old value of the isVisible 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.

  • commit( eventInfo, <anonymous> )

    See source

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    <anonymous> : Parameters<TObservable[ TName ]>

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

    See source

    Fired when the isEnabled 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 (isEnabled).

    value : boolean

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

    oldValue : boolean

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

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

    See source

    Fired when the isSelected 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 (isSelected).

    value : boolean

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

    oldValue : boolean

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

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

    See source

    Fired when the isVisible 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 (isVisible).

    value : boolean

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

    oldValue : boolean

    Old value of the isVisible 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.

  • updateSize( eventInfo, <anonymous> )

    See source

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    <anonymous> : Parameters<TObservable[ TName ]>