@ckeditor/ckeditor5-ui
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The UI framework and standard UI library of CKEditor 5.
211 lines (210 loc) • 7.62 kB
JavaScript
/**
* @license Copyright (c) 2003-2025, CKSource Holding sp. z o.o. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-licensing-options
*/
/**
* @module ui/viewcollection
*/
import { CKEditorError, Collection } from '@ckeditor/ckeditor5-utils';
/**
* Collects {@link module:ui/view~View} instances.
*
* ```ts
* const parentView = new ParentView( locale );
* const collection = new ViewCollection( locale );
*
* collection.setParent( parentView.element );
*
* const viewA = new ChildView( locale );
* const viewB = new ChildView( locale );
* ```
*
* View collection renders and manages view {@link module:ui/view~View#element elements}:
*
* ```ts
* collection.add( viewA );
* collection.add( viewB );
*
* console.log( parentView.element.firsChild ); // -> viewA.element
* console.log( parentView.element.lastChild ); // -> viewB.element
* ```
*
* It {@link module:ui/viewcollection~ViewCollection#delegate propagates} DOM events too:
*
* ```ts
* // Delegate #click and #keydown events from viewA and viewB to the parentView.
* collection.delegate( 'click' ).to( parentView );
*
* parentView.on( 'click', ( evt ) => {
* console.log( `${ evt.source } has been clicked.` );
* } );
*
* // This event will be delegated to the parentView.
* viewB.fire( 'click' );
* ```
*
* **Note**: A view collection can be used directly in the {@link module:ui/template~TemplateDefinition definition}
* of a {@link module:ui/template~Template template}.
*/
export default class ViewCollection extends Collection {
/**
* A parent element within which child views are rendered and managed in DOM.
*/
_parentElement;
/**
* Creates a new instance of the {@link module:ui/viewcollection~ViewCollection}.
*
* @param initialItems The initial items of the collection.
*/
constructor(initialItems = []) {
super(initialItems, {
// An #id Number attribute should be legal and not break the `ViewCollection` instance.
// https://github.com/ckeditor/ckeditor5-ui/issues/93
idProperty: 'viewUid'
});
// Handle {@link module:ui/view~View#element} in DOM when a new view is added to the collection.
this.on('add', (evt, view, index) => {
this._renderViewIntoCollectionParent(view, index);
});
// Handle {@link module:ui/view~View#element} in DOM when a view is removed from the collection.
this.on('remove', (evt, view) => {
if (view.element && this._parentElement) {
view.element.remove();
}
});
this._parentElement = null;
}
/**
* Destroys the view collection along with child views.
* See the view {@link module:ui/view~View#destroy} method.
*/
destroy() {
this.map(view => view.destroy());
}
/**
* Sets the parent HTML element of this collection. When parent is set, {@link #add adding} and
* {@link #remove removing} views in the collection synchronizes their
* {@link module:ui/view~View#element elements} in the parent element.
*
* @param elementOrDocFragment A new parent element or document fragment.
*/
setParent(elementOrDocFragment) {
this._parentElement = elementOrDocFragment;
// Take care of the initial collection items passed to the constructor.
for (const view of this) {
this._renderViewIntoCollectionParent(view);
}
}
/**
* Delegates selected events coming from within views in the collection to any
* {@link module:utils/emittermixin~Emitter}.
*
* For the following views and collection:
*
* ```ts
* const viewA = new View();
* const viewB = new View();
* const viewC = new View();
*
* const views = parentView.createCollection();
*
* views.delegate( 'eventX' ).to( viewB );
* views.delegate( 'eventX', 'eventY' ).to( viewC );
*
* views.add( viewA );
* ```
*
* the `eventX` is delegated (fired by) `viewB` and `viewC` along with `customData`:
*
* ```ts
* viewA.fire( 'eventX', customData );
* ```
*
* and `eventY` is delegated (fired by) `viewC` along with `customData`:
*
* ```ts
* viewA.fire( 'eventY', customData );
* ```
*
* See {@link module:utils/emittermixin~Emitter#delegate}.
*
* @param events {@link module:ui/view~View} event names to be delegated to another
* {@link module:utils/emittermixin~Emitter}.
* @returns Object with `to` property, a function which accepts the destination
* of {@link module:utils/emittermixin~Emitter#delegate delegated} events.
*/
delegate(...events) {
if (!events.length || !isStringArray(events)) {
/**
* All event names must be strings.
*
* @error ui-viewcollection-delegate-wrong-events
*/
throw new CKEditorError('ui-viewcollection-delegate-wrong-events', this);
}
return {
to: dest => {
// Activate delegating on existing views in this collection.
for (const view of this) {
for (const evtName of events) {
view.delegate(evtName).to(dest);
}
}
// Activate delegating on future views in this collection.
this.on('add', (evt, view) => {
for (const evtName of events) {
view.delegate(evtName).to(dest);
}
});
// Deactivate delegating when view is removed from this collection.
this.on('remove', (evt, view) => {
for (const evtName of events) {
view.stopDelegating(evtName, dest);
}
});
}
};
}
/**
* This method {@link module:ui/view~View#render renders} a new view added to the collection.
*
* If the {@link #_parentElement parent element} of the collection is set, this method also adds
* the view's {@link module:ui/view~View#element} as a child of the parent in DOM at a specified index.
*
* **Note**: If index is not specified, the view's element is pushed as the last child
* of the parent element.
*
* @param view A new view added to the collection.
* @param index An index the view holds in the collection. When not specified,
* the view is added at the end.
*/
_renderViewIntoCollectionParent(view, index) {
if (!view.isRendered) {
view.render();
}
if (view.element && this._parentElement) {
this._parentElement.insertBefore(view.element, this._parentElement.children[index]);
}
}
/**
* Removes a child view from the collection. If the {@link #setParent parent element} of the
* collection has been set, the {@link module:ui/view~View#element element} of the view is also removed
* in DOM, reflecting the order of the collection.
*
* See the {@link #add} method.
*
* @param subject The view to remove, its id or index in the collection.
* @returns The removed view.
*/
remove(subject) {
return super.remove(subject);
}
}
/**
* Check if all entries of the array are of `String` type.
*
* @param arr An array to be checked.
*/
function isStringArray(arr) {
return arr.every(a => typeof a == 'string');
}