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Class

BalloonPanelView (ui/panel/balloon)

@ckeditor/ckeditor5-ui/src/panel/balloon/balloonpanelview

class
See source

The balloon panel view class.

A floating container which can pin to any target in the DOM and remain in that position e.g. when the web page is scrolled.

The balloon panel can be used to display contextual, non-blocking UI like forms, toolbars and the like in its content view collection.

There is a number of defaultPositions that the balloon can use, automatically switching from one to another when the viewport space becomes scarce to keep the balloon visible to the user as long as it is possible. The balloon will also accept any custom position set provided by the user compatible with the options.

const panel = new BalloonPanelView( locale );
const childView = new ChildView();
const positions = BalloonPanelView.defaultPositions;

panel.render();

// Add a child view to the panel's content collection.
panel.content.add( childView );

// Start pinning the panel to an element with the "target" id DOM.
// The balloon will remain pinned until unpin() is called.
panel.pin( {
	target: document.querySelector( '#target' ),
	positions: [
		positions.northArrowSouth,
		positions.southArrowNorth
	]
} );

Filtering

Properties

  • readonly inherited

    bindTemplate : BindChain<this>

    See source

    Shorthand for bind, a binding interface pre–configured for the view instance.

    It provides to() and if() methods that initialize bindings with observable attributes and attach DOM listeners.

    class SampleView extends View {
	constructor( locale ) {
		super( locale );

		const bind = this.bindTemplate;

		// These observable attributes will control
		// the state of the view in DOM.
		this.set( {
			elementClass: 'foo',
		 	isEnabled: true
		 } );

		this.setTemplate( {
			tag: 'p',

			attributes: {
				// The class HTML attribute will follow elementClass
				// and isEnabled view attributes.
				class: [
					bind.to( 'elementClass' )
					bind.if( 'isEnabled', 'present-when-enabled' )
				]
			},

			on: {
				// The view will fire the "clicked" event upon clicking <p> in DOM.
				click: bind.to( 'clicked' )
			}
		} );
	}
}

  • observable

    class : undefined | string

    See source

    An additional CSS class added to the element.

  • readonly

    content : ViewCollection<View<HTMLElement>>

    See source

    A collection of the child views that creates the balloon panel contents.

  • inherited

    element : null | HTMLElement

    See source

    An HTML element of the view. null until rendered from the template.

    class SampleView extends View {
	constructor() {
		super();

		// A template instance the #element will be created from.
		this.setTemplate( {
			tag: 'p'

			// ...
		} );
	}
}

const view = new SampleView();

// Renders the #template.
view.render();

// Append the HTML element of the view to <body>.
document.body.appendChild( view.element );

    Note: The element of the view can also be assigned directly:

    view.element = document.querySelector( '#my-container' );

  • inherited

    isRendered : boolean

    See source

    Set true when the view has already been rendered.

  • observable

    isVisible : boolean

    See source

    Controls whether the balloon panel is visible or not.

    Defaults to false

  • observable

    left : number

    See source

    The absolute left position of the balloon panel in pixels.

    Defaults to 0

  • inherited

    locale : undefined | Locale

    See source

    A set of tools to localize the user interface.

    Also see locale.

  • observable

    position : 'arrow_nw' | 'arrow_ne' | 'arrow_sw' | 'arrow_se'

    See source

    The balloon panel's current position. The position name is reflected in the CSS class set to the balloon, i.e. .ck-balloon-panel_arrow_nw for the "arrow_nw" position. The class controls the minor aspects of the balloon's visual appearance like the placement of an arrow. To support a new position, an additional CSS must be created.

    Default position names correspond with defaultPositions.

    See the attachTo and pin methods to learn about custom balloon positions.

    Defaults to 'arrow_nw'

  • inherited

    t : undefined | LocaleTranslate

    See source

    Shorthand for t.

    Note: If locale instance hasn't been passed to the view this method may not be available.

    Related:

  • inherited

    template : Template | undefined

    See source

    Template of this view. It provides the element representing the view in DOM, which is rendered.

  • observable

    top : number

    See source

    The absolute top position of the balloon panel in pixels.

    Defaults to 0

  • inherited

    viewUid : string | undefined

    See source

  • observable

    withArrow : boolean

    See source

    Controls whether the balloon panel has an arrow. The presence of the arrow is reflected in the ck-balloon-panel_with-arrow CSS class.

    Defaults to true

  • protected inherited

    _unboundChildren : ViewCollection<View<HTMLElement>>

    See source

    A collection of view instances, which have been added directly into the children.

  • protected inherited

    _viewCollections : Collection<ViewCollection<View<HTMLElement>>>

    See source

    Collections registered with createCollection.

  • private

    _pinWhenIsVisibleCallback : null | () => void

    See source

    A callback that starts pinning the panel when isVisible gets true. Used by pin.

  • private

    _resizeObserver : null | ResizeObserver

    See source

    An instance of resize observer used to detect if target element is still visible.

Static properties

  • static

    arrowHeightOffset : number

    See source

    A height offset of the arrow from the edge of the balloon. Controlled by CSS.

    		 ┌───────────────────────┐
		 │                       │
		 │         Balloon       │
		 │         Content       │      ╱-- arrow height offset
		 │                       │      V
		 └──+    +───────────────┘ --- ─┼───────
		     \  /                       │
		      /                        │
		────────────────────────────────┼───────
		                                ^


		>┼────┼<  arrow height offset
		 │    │
		 │    ┌────────────────────────┐
		 │    │                        │
		 │   ╱                         │
		 │ ╱            Balloon        │
		 │ ╲            Content        │
		 │   ╲                         │
		 │    │                        │
		 │    └────────────────────────┘

    Defaults to 10

  • static

    arrowSideOffset : number

    See source

    A side offset of the arrow tip from the edge of the balloon. Controlled by CSS.

    		 ┌───────────────────────┐
		 │                       │
		 │         Balloon       │
		 │         Content       │
		 │                       │
		 └──+    +───────────────┘
		 |   \  /
		 |    /
		>┼─────┼< ─────────────────────── side offset

    Defaults to 25

  • static

    defaultPositions : Record<string, PositioningFunction>

    See source

    A default set of positioning functions used by the balloon panel view when attaching using the attachTo method.

    The available positioning functions are as follows:

    North west

    • northWestArrowSouthWest
    		+-----------------+
		|     Balloon     |
		+-----------------+
		 V
		 [ Target ]
    • northWestArrowSouthMiddleWest
    		+-----------------+
		|     Balloon     |
		+-----------------+
		    V
		    [ Target ]
    • northWestArrowSouth
    		+-----------------+
		|     Balloon     |
		+-----------------+
		         V
		         [ Target ]
    • northWestArrowSouthMiddleEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		             V
		             [ Target ]
    • northWestArrowSouthEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		                 V
		                 [ Target ]

    North

    • northArrowSouthWest
    		    +-----------------+
		    |     Balloon     |
		    +-----------------+
		     V
		[ Target ]
    • northArrowSouthMiddleWest
    		 +-----------------+
		 |     Balloon     |
		 +-----------------+
		     V
		[ Target ]
    • northArrowSouth
    		+-----------------+
		|     Balloon     |
		+-----------------+
		         V
		    [ Target ]
    • northArrowSouthMiddleEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		             V
		        [ Target ]
    • northArrowSouthEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		                V
		           [ Target ]

    North east

    • northEastArrowSouthWest
    		        +-----------------+
		        |     Balloon     |
		        +-----------------+
		         V
		[ Target ]
    • northEastArrowSouthMiddleWest
    		     +-----------------+
		     |     Balloon     |
		     +-----------------+
		         V
		[ Target ]
    • northEastArrowSouth
    		+-----------------+
		|     Balloon     |
		+-----------------+
		         V
		[ Target ]
    • northEastArrowSouthMiddleEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		             V
		    [ Target ]
    • northEastArrowSouthEast
    		+-----------------+
		|     Balloon     |
		+-----------------+
		                 V
		        [ Target ]

    South

    • southArrowNorthWest
    		[ Target ]
		     ^
		    +-----------------+
		    |     Balloon     |
		    +-----------------+
    • southArrowNorthMiddleWest
    		   [ Target ]
		        ^
		    +-----------------+
		    |     Balloon     |
		    +-----------------+
    • southArrowNorth
    		    [ Target ]
		         ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southArrowNorthMiddleEast
    		            [ Target ]
		                 ^
		   +-----------------+
		   |     Balloon     |
		   +-----------------+
    • southArrowNorthEast
    		            [ Target ]
		                 ^
		+-----------------+
		|     Balloon     |
		+-----------------+

    South west

    • southWestArrowNorthWest
    		 [ Target ]
		 ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southWestArrowNorthMiddleWest
    		     [ Target ]
		     ^
		 +-----------------+
		 |     Balloon     |
		 +-----------------+
    • southWestArrowNorth
    		         [ Target ]
		         ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southWestArrowNorthMiddleEast
    		              [ Target ]
		              ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southWestArrowNorthEast
    		                 [ Target ]
		                 ^
		+-----------------+
		|     Balloon     |
		+-----------------+

    South east

    • southEastArrowNorthWest
    		[ Target ]
		         ^
		        +-----------------+
		        |     Balloon     |
		        +-----------------+
    • southEastArrowNorthMiddleWest
    		   [ Target ]
		            ^
		        +-----------------+
		        |     Balloon     |
		        +-----------------+
    • southEastArrowNorth
    		[ Target ]
		         ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southEastArrowNorthMiddleEast
    		     [ Target ]
		              ^
		+-----------------+
		|     Balloon     |
		+-----------------+
    • southEastArrowNorthEast
    		        [ Target ]
		                 ^
		+-----------------+
		|     Balloon     |
		+-----------------+

    West

    • westArrowEast
    		+-----------------+
		|     Balloon     |>[ Target ]
		+-----------------+

    East

    • eastArrowWest
    		           +-----------------+
		[ Target ]<|     Balloon     |
		           +-----------------+

    Sticky

    • viewportStickyNorth
    		    +---------------------------+
		    |        [ Target ]         |
		    |                           |
		+-----------------------------------+
		|   |    +-----------------+    |   |
		|   |    |     Balloon     |    |   |
		|   |    +-----------------+    |   |
		|   |                           |   |
		|   |                           |   |
		|   |                           |   |
		|   |                           |   |
		|   +---------------------------+   |
		|             Viewport              |
		+-----------------------------------+

    See attachTo.

    Positioning functions must be compatible with DomPoint.

    Default positioning functions with customized offsets can be generated using generatePositions.

    The name that the position function returns will be reflected in the balloon panel's class that controls the placement of the "arrow". See position to learn more.

  • static

    stickyVerticalOffset : number

    See source

    A vertical offset of the balloon panel from the edge of the viewport if sticky. It helps in accessing toolbar buttons underneath the balloon panel.

    		  ┌───────────────────────────────────────────────────┐
		  │                      Target                       │
		  │                                                   │
		  │                            /── vertical offset    │
		┌─────────────────────────────V─────────────────────────┐
		│ Toolbar            ┌─────────────┐                    │
		├────────────────────│   Balloon   │────────────────────┤
		│ │                  └─────────────┘                  │ │
		│ │                                                   │ │
		│ │                                                   │ │
		│ │                                                   │ │
		│ └───────────────────────────────────────────────────┘ │
		│                        Viewport                       │
		└───────────────────────────────────────────────────────┘

    Defaults to 20

  • private static

    _getOptimalPosition : ( Options ) => ( DomPoint | null )

    See source

    Function used to calculate the optimal position for the balloon.

Methods

  • constructor( [ locale ] )

    See source

    Parameters

    [ locale ] : Locale

  • attachTo( options ) → boolean

    See source

    Attaches the panel to a specified target with a smart positioning heuristics that chooses from available positions to make sure the panel is visible to the user i.e. within the limits of the viewport.

    This method accepts configuration options to set the target, optional limiter and positions the balloon should choose from.

    const panel = new BalloonPanelView( locale );
const positions = BalloonPanelView.defaultPositions;

panel.render();

// Attach the panel to an element with the "target" id DOM.
panel.attachTo( {
	target: document.querySelector( '#target' ),
	positions: [
		positions.northArrowSouth,
		positions.southArrowNorth
	]
} );

    Note: Attaching the panel will also automatically show it.

    Note: An attached panel will not follow its target when the window is scrolled or resized. See the pin method for a more permanent positioning strategy.

    Parameters

    options : Partial<Options>

    Positioning options compatible with getOptimalPosition. Default positions array is defaultPositions.

    Returns

    boolean

    Whether the balloon was shown and successfully attached or not. Attaching can fail if the target provided in the options is invisible (e.g. element detached from DOM).

  • inherited

    bind( bindProperty1, bindProperty2 ) → DualBindChain<K1, BalloonPanelView[ K1 ], K2, BalloonPanelView[ 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, BalloonPanelView[ K1 ], K2, BalloonPanelView[ 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' | 'element' | 'template' | 'top' | 'left' | 'isRendered' | 'locale' | 't' | 'viewUid' | 'bindTemplate' | 'createCollection' | 'registerChild' | 'deregisterChild' | 'setTemplate' | 'extendTemplate' | 'render' | 'destroy' | 'class' | 'content' | 'isVisible' | 'withArrow' | 'position' | 'show' | 'hide' | 'attachTo' | 'pin' | 'unpin'>

    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, BalloonPanelView[ 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, BalloonPanelView[ K ]>

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

  • inherited

    createCollection( [ views ] ) → ViewCollection<T>

    See source

    Creates a new collection of views, which can be used as children of this view.

    class SampleView extends View {
	constructor( locale ) {
		super( locale );

		const child = new ChildView( locale );
		this.items = this.createCollection( [ child ] );
 *
		this.setTemplate( {
			tag: 'p',

			// `items` collection will render here.
			children: this.items
		} );
	}
}

const view = new SampleView( locale );
view.render();

// It will append <p><child#element></p> to the <body>.
document.body.appendChild( view.element );

    Type parameters

    T : extends [object Object] = default

    Parameters

    [ views ] : Iterable<T>

    Initial views of the collection.

    Returns

    ViewCollection<T>

    A new collection of view instances.

  • 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' | 'element' | 'template' | 'top' | 'left' | 'isRendered' | 'locale' | 't' | 'viewUid' | 'bindTemplate' | 'createCollection' | 'registerChild' | 'deregisterChild' | 'setTemplate' | 'extendTemplate' | 'render' | 'destroy' | 'class' | 'content' | 'isVisible' | 'withArrow' | 'position' | 'show' | 'hide' | 'attachTo' | 'pin' | 'unpin'

    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

    deregisterChild( children ) → void

    See source

    The opposite of registerChild. Removes a child view from this view instance. Once removed, the child is no longer managed by its parent, e.g. it can safely become a child of another parent view.

    Parameters

    children : View<HTMLElement> | Iterable<View<HTMLElement>>

    Child views to be removed.

    Returns

    void

    Related:

  • destroy() → void

    See source

    Recursively destroys the view instance and child views added by registerChild and residing in collections created by the createCollection.

    Destruction disables all event listeners:

    • created on the view, e.g. view.on( 'event', () => {} ),
    • defined in the template for DOM events.

    Returns

    void

  • inherited

    extendTemplate( definition ) → void

    See source

    Extends the template of the view with with given definition.

    A shorthand for:

    Template.extend( view.template, definition );

    Note: Is requires the template to be already set. See setTemplate.

    Parameters

    definition : Partial<TemplateDefinition>

    Definition which extends the template.

    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 the panel.

    See isVisible.

    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 ] : CallbackOptions

    Additional options.

    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

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

    See source

    Registers a callback function to be executed when an event is fired in a specific Emitter or DOM Node. It is backwards compatible with listenTo.

    Type parameters

    K : extends keyof DomEventMap

    Parameters

    emitter : Window | Node

    The object that fires the event.

    event : K

    The name of the event.

    callback : ( BalloonPanelView, EventInfo<string, unknown>, DomEventMap[ K ] ) => void

    The function to be called on event.

    [ options ] : object

    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

  • pin( options ) → void

    See source

    Works the same way as the attachTo method except that the position of the panel is continuously updated when:

    • any ancestor of the target or limiter is scrolled,
    • the browser window gets resized or scrolled.

    Thanks to that, the panel always sticks to the target and is immune to the changing environment.

    const panel = new BalloonPanelView( locale );
const positions = BalloonPanelView.defaultPositions;

panel.render();

// Pin the panel to an element with the "target" id DOM.
panel.pin( {
	target: document.querySelector( '#target' ),
	positions: [
		positions.northArrowSouth,
		positions.southArrowNorth
	]
} );

    To leave the pinned state, use the unpin method.

    Note: Pinning the panel will also automatically show it.

    Parameters

    options : Partial<Options>

    Positioning options compatible with getOptimalPosition. Default positions array is defaultPositions.

    Returns

    void

  • inherited

    registerChild( children ) → void

    See source

    Registers a new child view under the view instance. Once registered, a child view is managed by its parent, including rendering and destruction.

    To revert this, use deregisterChild.

    class SampleView extends View {
	constructor( locale ) {
		super( locale );

		this.childA = new SomeChildView( locale );
		this.childB = new SomeChildView( locale );

		this.setTemplate( { tag: 'p' } );

		// Register the children.
		this.registerChild( [ this.childA, this.childB ] );
	}

	render() {
		super.render();

		this.element.appendChild( this.childA.element );
		this.element.appendChild( this.childB.element );
	}
}

const view = new SampleView( locale );

view.render();

// Will append <p><childA#element><b></b><childB#element></p>.
document.body.appendChild( view.element );

    Note: There's no need to add child views if they're already referenced in the template:

    class SampleView extends View {
	constructor( locale ) {
		super( locale );

		this.childA = new SomeChildView( locale );
		this.childB = new SomeChildView( locale );

		this.setTemplate( {
			tag: 'p',

 * 			// These children will be added automatically. There's no
 * 			// need to call registerChild for any of them.
			children: [ this.childA, this.childB ]
		} );
	}

	// ...
}

    Parameters

    children : View<HTMLElement> | Iterable<View<HTMLElement>>

    Children views to be registered.

    Returns

    void

  • inherited

    render() → void

    See source

    Recursively renders the view.

    Once the view is rendered:

    Note: The children of the view:

    In general, render() method is the right place to keep the code which refers to the element and should be executed at the very beginning of the view's life cycle.

    It is possible to extend the template before the view is rendered. To allow an early customization of the view (e.g. by its parent), such references should be done in render().

    class SampleView extends View {
	constructor() {
		this.setTemplate( {
			// ...
		} );
	},

	render() {
		// View#element becomes available.
		super.render();

		// The "scroll" listener depends on #element.
		this.listenTo( window, 'scroll', () => {
			// A reference to #element would render the #template and make it non-extendable.
			if ( window.scrollY > 0 ) {
				this.element.scrollLeft = 100;
			} else {
				this.element.scrollLeft = 0;
			}
		} );
	}
}

const view = new SampleView();

// Let's customize the view before it gets rendered.
view.extendTemplate( {
	attributes: {
		class: [
			'additional-class'
		]
	}
} );

// Late rendering allows customization of the view.
view.render();

    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 : BalloonPanelView[ K ]

    The property's value.

    Returns

    void

  • inherited

    setTemplate( definition ) → void

    See source

    Sets the template of the view with with given definition.

    A shorthand for:

    view.setTemplate( definition );

    Parameters

    definition : TemplateDefinition

    Definition of view's template.

    Returns

    void

  • show() → void

    See source

    Shows the panel.

    See isVisible.

    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

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

    See source

    Stops listening for events. It can be used at different levels: It is backwards compatible with listenTo.

    • 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 ] : Window | Node | 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' | 'element' | 'template' | 'top' | 'left' | 'isRendered' | 'locale' | 't' | 'viewUid' | 'bindTemplate' | 'createCollection' | 'registerChild' | 'deregisterChild' | 'setTemplate' | 'extendTemplate' | 'render' | 'destroy' | 'class' | 'content' | 'isVisible' | 'withArrow' | 'position' | 'show' | 'hide' | 'attachTo' | 'pin' | 'unpin'>

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

    Returns

    void

  • unpin() → void

    See source

    Stops pinning the panel, as set up by pin.

    Returns

    void

  • private

    _startPinning( options ) → boolean

    See source

    Starts managing the pinned state of the panel. See pin.

    Parameters

    options : Partial<Options>

    Positioning options compatible with getOptimalPosition.

    Returns

    boolean

    Whether the balloon was shown and successfully attached or not. Attaching can fail if the target provided in the options is invisible (e.g. element detached from DOM).

  • private

    _stopPinning() → void

    See source

    Stops managing the pinned state of the panel. See pin.

    Returns

    void

Static methods

  • internal static

    generatePositions( options = { [options.config], [options.heightOffset], [options.sideOffset], [options.stickyVerticalOffset] } ) → Record<string, PositioningFunction>

    See source

    Returns available BalloonPanelView positioning functions adjusted by the specific offsets.

    Parameters

    options : object

    Options to generate positions. If not specified, this helper will simply return defaultPositions.

    Properties
    [ options.config ] : object

    Additional configuration of the balloon balloon panel view. Currently only withArrow is supported. Learn more about positioning functions.

    [ options.heightOffset ] : number

    A custom height offset (in pixels) of each position. If not specified, the default value will be used.

    [ options.sideOffset ] : number

    A custom side offset (in pixels) of each position. If not specified, the default value will be used.

    [ options.stickyVerticalOffset ] : number

    A custom offset (in pixels) of the viewportStickyNorth positioning function. If not specified, the default value will be used.

    Defaults to {}

    Returns

    Record<string, PositioningFunction>

Events

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

    See source

    Fired when the class property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (class).

    value : undefined | string

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

    oldValue : undefined | string

    Old value of the class 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.

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

    See source

    Fired when the left property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (left).

    value : number

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

    oldValue : number

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

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

    See source

    Fired when the position property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (position).

    value : 'arrow_nw' | 'arrow_ne' | 'arrow_sw' | 'arrow_se'

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

    oldValue : 'arrow_nw' | 'arrow_ne' | 'arrow_sw' | 'arrow_se'

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

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

    See source

    Fired when the top property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (top).

    value : number

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

    oldValue : number

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

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

    See source

    Fired when the withArrow property changed value.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    name : string

    Name of the changed property (withArrow).

    value : boolean

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

    oldValue : boolean

    Old value of the withArrow 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.

  • inherited

    render( eventInfo, <anonymous> )

    See source

    Event fired by the render method. Actual rendering is executed as a listener to this event with the default priority.

    See decorate for more information and samples.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.

    <anonymous> : Parameters<TObservable[ TName ]>

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

    See source

    Fired when the class 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 (class).

    value : undefined | string

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

    oldValue : undefined | string

    Old value of the class 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.

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

    See source

    Fired when the left 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 (left).

    value : number

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

    oldValue : number

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

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

    See source

    Fired when the position 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 (position).

    value : 'arrow_nw' | 'arrow_ne' | 'arrow_sw' | 'arrow_se'

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

    oldValue : 'arrow_nw' | 'arrow_ne' | 'arrow_sw' | 'arrow_se'

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

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

    See source

    Fired when the top 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 (top).

    value : number

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

    oldValue : number

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

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

    See source

    Fired when the withArrow 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 (withArrow).

    value : boolean

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

    oldValue : boolean

    Old value of the withArrow 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.

  • inherited

    submit( eventInfo )

    See source

    Fired by submitHandler helper.

    Parameters

    eventInfo : EventInfo

    An object containing information about the fired event.