@ckeditor/ckeditor5-ui
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The UI framework and standard UI library of CKEditor 5.
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TypeScript
/**
* @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/template
*/
import View from './view.js';
import ViewCollection from './viewcollection.js';
import { type ArrayOrItem, type Emitter, type Observable } from '@ckeditor/ckeditor5-utils';
declare const Template_base: {
new (): Emitter;
prototype: Emitter;
};
/**
* A basic Template class. It renders a DOM HTML element or text from a
* {@link module:ui/template~TemplateDefinition definition} and supports element attributes, children,
* bindings to {@link module:utils/observablemixin~Observable observables} and DOM event propagation.
*
* A simple template can look like this:
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* attributes: {
* class: 'foo',
* style: {
* backgroundColor: 'yellow'
* }
* },
* on: {
* click: bind.to( 'clicked' )
* },
* children: [
* 'A paragraph.'
* ]
* } ).render();
* ```
*
* and it will render the following HTML element:
*
* ```html
* <p class="foo" style="background-color: yellow;">A paragraph.</p>
* ```
*
* Additionally, the `observable` will always fire `clicked` upon clicking `<p>` in the DOM.
*
* See {@link module:ui/template~TemplateDefinition} to know more about templates and complex
* template definitions.
*/
export default class Template extends /* #__PURE__ */ Template_base {
ns?: string;
/**
* The tag (`tagName`) of this template, e.g. `div`. It also indicates that the template
* renders to an HTML element.
*/
tag?: string;
/**
* The text of the template. It also indicates that the template renders to a DOM text node.
*/
text?: Array<TemplateSimpleValue | TemplateBinding>;
/**
* The attributes of the template, e.g. `{ id: [ 'ck-id' ] }`, corresponding with
* the attributes of an HTML element.
*
* **Note**: This property only makes sense when {@link #tag} is defined.
*/
attributes?: Record<string, AttributeValues>;
/**
* The children of the template. They can be either:
* * independent instances of {@link ~Template} (sub–templates),
* * native DOM Nodes.
*
* **Note**: This property only makes sense when {@link #tag} is defined.
*/
children?: Array<ViewCollection | View | Node | Template>;
/**
* The DOM event listeners of the template.
*/
eventListeners?: Record<string, Array<TemplateToBinding>>;
/**
* Indicates whether this particular Template instance has been
* {@link #render rendered}.
*/
private _isRendered;
/**
* The data used by the {@link #revert} method to restore a node to its original state.
*
* See: {@link #apply}.
*/
private _revertData;
/**
* Creates an instance of the {@link ~Template} class.
*
* @param def The definition of the template.
*/
constructor(def: TemplateDefinition);
/**
* Renders a DOM Node (an HTML element or text) out of the template.
*
* ```ts
* const domNode = new Template( { ... } ).render();
* ```
*
* See: {@link #apply}.
*/
render(): HTMLElement | Text;
/**
* Applies the template to an existing DOM Node, either HTML element or text.
*
* **Note:** No new DOM nodes will be created. Applying extends:
*
* {@link module:ui/template~TemplateDefinition attributes},
* {@link module:ui/template~TemplateDefinition event listeners}, and
* `textContent` of {@link module:ui/template~TemplateDefinition children} only.
*
* **Note:** Existing `class` and `style` attributes are extended when a template
* is applied to an HTML element, while other attributes and `textContent` are overridden.
*
* **Note:** The process of applying a template can be easily reverted using the
* {@link module:ui/template~Template#revert} method.
*
* ```ts
* const element = document.createElement( 'div' );
* const observable = new Model( { divClass: 'my-div' } );
* const emitter = Object.create( EmitterMixin );
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* attributes: {
* id: 'first-div',
* class: bind.to( 'divClass' )
* },
* on: {
* click: bind( 'elementClicked' ) // Will be fired by the observable.
* },
* children: [
* 'Div text.'
* ]
* } ).apply( element );
*
* console.log( element.outerHTML ); // -> '<div id="first-div" class="my-div"></div>'
* ```
*
* @see module:ui/template~Template#render
* @see module:ui/template~Template#revert
* @param node Root node for the template to apply.
*/
apply(node: HTMLElement | Text): HTMLElement | Text;
/**
* Reverts a template {@link module:ui/template~Template#apply applied} to a DOM node.
*
* @param node The root node for the template to revert. In most of the cases, it is the
* same node used by {@link module:ui/template~Template#apply}.
*/
revert(node: HTMLElement | Text): void;
/**
* Returns an iterator which traverses the template in search of {@link module:ui/view~View}
* instances and returns them one by one.
*
* ```ts
* const viewFoo = new View();
* const viewBar = new View();
* const viewBaz = new View();
* const template = new Template( {
* tag: 'div',
* children: [
* viewFoo,
* {
* tag: 'div',
* children: [
* viewBar
* ]
* },
* viewBaz
* ]
* } );
*
* // Logs: viewFoo, viewBar, viewBaz
* for ( const view of template.getViews() ) {
* console.log( view );
* }
* ```
*/
getViews(): IterableIterator<View>;
/**
* An entry point to the interface which binds DOM nodes to
* {@link module:utils/observablemixin~Observable observables}.
* There are two types of bindings:
*
* * HTML element attributes or text `textContent` synchronized with attributes of an
* {@link module:utils/observablemixin~Observable}. Learn more about {@link module:ui/template~BindChain#to}
* and {@link module:ui/template~BindChain#if}.
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* attributes: {
* // Binds the element "class" attribute to observable#classAttribute.
* class: bind.to( 'classAttribute' )
* }
* } ).render();
* ```
*
* * DOM events fired on HTML element propagated through
* {@link module:utils/observablemixin~Observable}. Learn more about {@link module:ui/template~BindChain#to}.
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* on: {
* // Will be fired by the observable.
* click: bind( 'elementClicked' )
* }
* } ).render();
* ```
*
* Also see {@link module:ui/view~View#bindTemplate}.
*
* @param observable An observable which provides boundable attributes.
* @param emitter An emitter that listens to observable attribute
* changes or DOM Events (depending on the kind of the binding). Usually, a {@link module:ui/view~View} instance.
*/
static bind<TObservable extends Observable>(observable: TObservable, emitter: Emitter): BindChain<TObservable>;
/**
* Extends an existing {@link module:ui/template~Template} instance with some additional content
* from another {@link module:ui/template~TemplateDefinition}.
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* const template = new Template( {
* tag: 'p',
* attributes: {
* class: 'a',
* data-x: bind.to( 'foo' )
* },
* children: [
* {
* tag: 'span',
* attributes: {
* class: 'b'
* },
* children: [
* 'Span'
* ]
* }
* ]
* } );
*
* // Instance-level extension.
* Template.extend( template, {
* attributes: {
* class: 'b',
* data-x: bind.to( 'bar' )
* },
* children: [
* {
* attributes: {
* class: 'c'
* }
* }
* ]
* } );
*
* // Child extension.
* Template.extend( template.children[ 0 ], {
* attributes: {
* class: 'd'
* }
* } );
* ```
*
* the `outerHTML` of `template.render()` is:
*
* ```html
* <p class="a b" data-x="{ observable.foo } { observable.bar }">
* <span class="b c d">Span</span>
* </p>
* ```
*
* @param template An existing template instance to be extended.
* @param def Additional definition to be applied to a template.
*/
static extend(template: Template, def: Partial<TemplateDefinition>): void;
/**
* Renders a DOM Node (either an HTML element or text) out of the template.
*
* @param data Rendering data.
*/
private _renderNode;
/**
* Renders an HTML element out of the template.
*
* @param data Rendering data.
*/
private _renderElement;
/**
* Renders a text node out of {@link module:ui/template~Template#text}.
*
* @param data Rendering data.
*/
private _renderText;
/**
* Renders HTML element attributes out of {@link module:ui/template~Template#attributes}.
*
* @param data Rendering data.
*/
private _renderAttributes;
/**
* Renders the `style` attribute of an HTML element based on
* {@link module:ui/template~Template#attributes}.
*
* A style attribute is an object with static values:
*
* ```ts
* attributes: {
* style: {
* color: 'red'
* }
* }
* ```
*
* or values bound to {@link module:ui/model~Model} properties:
*
* ```ts
* attributes: {
* style: {
* color: bind.to( ... )
* }
* }
* ```
*
* Note: The `style` attribute is rendered without setting the namespace. It does not seem to be
* needed.
*
* @param styles Styles located in `attributes.style` of {@link module:ui/template~TemplateDefinition}.
* @param data Rendering data.
*/
private _renderStyleAttribute;
/**
* Recursively renders HTML element's children from {@link module:ui/template~Template#children}.
*
* @param data Rendering data.
*/
private _renderElementChildren;
/**
* Activates `on` event listeners from the {@link module:ui/template~TemplateDefinition}
* on an HTML element.
*
* @param data Rendering data.
*/
private _setUpListeners;
/**
* For a given {@link module:ui/template~TemplateValueSchema} containing {@link module:ui/template~TemplateBinding}
* activates the binding and sets its initial value.
*
* Note: {@link module:ui/template~TemplateValueSchema} can be for HTML element attributes or
* text node `textContent`.
*
* @param options Binding options.
* @param options.updater A function which updates the DOM (like attribute or text).
* @param options.data Rendering data.
*/
private _bindToObservable;
/**
* Reverts {@link module:ui/template~RenderData#revertData template data} from a node to
* return it to the original state.
*
* @param node A node to be reverted.
* @param revertData An object that stores information about what changes have been made by
* {@link #apply} to the node. See {@link module:ui/template~RenderData#revertData} for more information.
*/
private _revertTemplateFromNode;
}
type AttributeValues = Array<TemplateSimpleValue | TemplateBinding> | [
NamespacedValue<Array<TemplateSimpleValue | TemplateBinding>>
];
/**
* Describes a binding created by the {@link module:ui/template~Template.bind} interface.
*
* @internal
*/
export declare abstract class TemplateBinding {
/**
* The name of the {@link module:ui/template~TemplateBinding#observable observed attribute}.
*/
readonly attribute: string;
/**
* An observable instance of the binding. It either:
*
* * provides the attribute with the value,
* * or passes the event when a corresponding DOM event is fired.
*/
readonly observable: Observable;
/**
* An {@link module:utils/emittermixin~Emitter} used by the binding to:
*
* * listen to the attribute change in the {@link module:ui/template~TemplateBinding#observable},
* * or listen to the event in the DOM.
*/
readonly emitter: Emitter;
/**
* A custom function to process the value of the {@link module:ui/template~TemplateBinding#attribute}.
*/
readonly callback?: (value: any, node: Node) => TemplateSimpleValue;
/**
* Creates an instance of the {@link module:ui/template~TemplateBinding} class.
*
* @param def The definition of the binding.
*/
constructor(def: {
attribute: string;
observable: Observable;
emitter: Emitter;
callback?: (value: any, node: Node) => TemplateSimpleValue;
});
/**
* Returns the value of the binding. It is the value of the {@link module:ui/template~TemplateBinding#attribute} in
* {@link module:ui/template~TemplateBinding#observable}. The value may be processed by the
* {@link module:ui/template~TemplateBinding#callback}, if such has been passed to the binding.
*
* @param node A native DOM node, passed to the custom {@link module:ui/template~TemplateBinding#callback}.
* @returns The value of {@link module:ui/template~TemplateBinding#attribute} in
* {@link module:ui/template~TemplateBinding#observable}.
*/
getValue(node: Node): TemplateSimpleValue;
/**
* Activates the listener which waits for changes of the {@link module:ui/template~TemplateBinding#attribute} in
* {@link module:ui/template~TemplateBinding#observable}, then updates the DOM with the aggregated
* value of {@link module:ui/template~TemplateValueSchema}.
*
* @param schema A full schema to generate an attribute or text in the DOM.
* @param updater A DOM updater function used to update the native DOM attribute or text.
* @param data Rendering data.
* @returns A function to sever the listener binding.
*/
activateAttributeListener(schema: Array<TemplateSimpleValue | TemplateBinding>, updater: Updater, data: RenderData): () => void;
}
/**
* Describes either:
*
* * a binding to an {@link module:utils/observablemixin~Observable},
* * or a native DOM event binding.
*
* It is created by the {@link module:ui/template~BindChain#to} method.
*
* @internal
*/
export declare class TemplateToBinding extends TemplateBinding {
readonly eventNameOrFunction: string | ((domEvent: Event) => void);
constructor(def: ConstructorParameters<typeof TemplateBinding>[0] & {
eventNameOrFunction: string | ((domEvent: Event) => void);
});
/**
* Activates the listener for the native DOM event, which when fired, is propagated by
* the {@link module:ui/template~TemplateBinding#emitter}.
*
* @param domEvtName The name of the native DOM event.
* @param domSelector The selector in the DOM to filter delegated events.
* @param data Rendering data.
* @returns A function to sever the listener binding.
*/
activateDomEventListener(domEvtName: string, domSelector: string, data: {
node: any;
}): () => void;
}
/**
* Describes a binding to {@link module:utils/observablemixin~Observable} created by the {@link module:ui/template~BindChain#if}
* method.
*
* @internal
*/
export declare class TemplateIfBinding extends TemplateBinding {
/**
* The value of the DOM attribute or text to be set if the {@link module:ui/template~TemplateBinding#attribute} in
* {@link module:ui/template~TemplateBinding#observable} is `true`.
*/
readonly valueIfTrue?: string;
constructor(def: ConstructorParameters<typeof TemplateBinding>[0] & {
valueIfTrue?: string;
});
/**
* @inheritDoc
*/
getValue(node: Node): TemplateSimpleValue;
}
interface Updater {
set(value: any): void;
remove(): void;
}
/**
* A definition of the {@link module:ui/template~Template}. It describes what kind of
* node a template will render (HTML element or text), attributes of an element, DOM event
* listeners and children.
*
* Also see:
* * {@link module:ui/template~TemplateValueSchema} to learn about HTML element attributes,
* * {@link module:ui/template~TemplateListenerSchema} to learn about DOM event listeners.
*
* A sample definition on an HTML element can look like this:
*
* ```ts
* new Template( {
* tag: 'p',
* children: [
* {
* tag: 'span',
* attributes: { ... },
* children: [ ... ],
* },
* {
* text: 'static–text'
* },
* 'also-static–text',
* ],
* attributes: {
* class: {@link module:ui/template~TemplateValueSchema},
* id: {@link module:ui/template~TemplateValueSchema},
* style: {@link module:ui/template~TemplateValueSchema}
*
* // ...
* },
* on: {
* 'click': {@link module:ui/template~TemplateListenerSchema}
*
* // Document.querySelector format is also accepted.
* 'keyup@a.some-class': {@link module:ui/template~TemplateListenerSchema}
*
* // ...
* }
* } );
* ```
*
* A {@link module:ui/view~View}, another {@link module:ui/template~Template} or a native DOM node
* can also become a child of a template. When a view is passed, its {@link module:ui/view~View#element} is used:
*
* ```ts
* const view = new SomeView();
* const childTemplate = new Template( { ... } );
* const childNode = document.createElement( 'b' );
*
* new Template( {
* tag: 'p',
*
* children: [
* // view#element will be added as a child of this <p>.
* view,
*
* // The output of childTemplate.render() will be added here.
* childTemplate,
*
* // Native DOM nodes are included directly in the rendered output.
* childNode
* ]
* } );
* ```
*
* An entire {@link module:ui/viewcollection~ViewCollection} can be used as a child in the definition:
*
* ```ts
* const collection = new ViewCollection();
* collection.add( someView );
*
* new Template( {
* tag: 'p',
*
* children: collection
* } );
* ```
*/
export type TemplateDefinition = string | Template | TemplateElementDefinition | TemplateTextDefinition;
export type TemplateElementDefinition = {
/**
* See the template {@link module:ui/template~Template#tag} property.
*/
tag: string;
/**
* See the template {@link module:ui/template~Template#attributes} property.
*/
attributes?: Record<string, TemplateValueSchema>;
/**
* See the template {@link module:ui/template~Template#children} property.
*/
children?: Iterable<View | Node | Template | TemplateDefinition>;
/**
* See the template {@link module:ui/template~Template#eventListeners} property.
*/
on?: Record<string, TemplateListenerSchema>;
};
export type TemplateTextDefinition = {
/**
* See the template {@link module:ui/template~Template#text} property.
*/
text: ArrayOrItem<TemplateSimpleValueSchema>;
};
export type FalsyValue = false | null | undefined | '';
export type NamespacedValue<T> = {
ns: string;
value: T;
};
export type TemplateSimpleValue = string | boolean | number | null | undefined;
export type TemplateSimpleValueSchema = TemplateSimpleValue | AttributeBinding;
/**
* Describes a value of an HTML element attribute or `textContent`. It allows combining multiple
* data sources like static values and {@link module:utils/observablemixin~Observable} attributes.
*
* Also see:
* * {@link module:ui/template~TemplateDefinition} to learn where to use it,
* * {@link module:ui/template~Template.bind} to learn how to configure
* {@link module:utils/observablemixin~Observable} attribute bindings,
* * {@link module:ui/template~Template#render} to learn how to render a template,
* * {@link module:ui/template~BindChain#to `to()`} and {@link module:ui/template~BindChain#if `if()`}
* methods to learn more about bindings.
*
* Attribute values can be described in many different ways:
*
* ```ts
* // Bind helper will create bindings to attributes of the observable.
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* attributes: {
* // A plain string schema.
* 'class': 'static-text',
*
* // An object schema, binds to the "foo" attribute of the
* // observable and follows its value.
* 'class': bind.to( 'foo' ),
*
* // An array schema, combines the above.
* 'class': [
* 'static-text',
* bind.to( 'bar', () => { ... } ),
*
* // Bindings can also be conditional.
* bind.if( 'baz', 'class-when-baz-is-true' )
* ],
*
* // An array schema, with a custom namespace, e.g. useful for creating SVGs.
* 'class': {
* ns: 'http://ns.url',
* value: [
* bind.if( 'baz', 'value-when-true' ),
* 'static-text'
* ]
* },
*
* // An object schema, specific for styles.
* style: {
* color: 'red',
* backgroundColor: bind.to( 'qux', () => { ... } )
* }
* }
* } );
* ```
*
* Text nodes can also have complex values:
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* // Will render a "foo" text node.
* new Template( {
* text: 'foo'
* } );
*
* // Will render a "static text: {observable.foo}" text node.
* // The text of the node will be updated as the "foo" attribute changes.
* new Template( {
* text: [
* 'static text: ',
* bind.to( 'foo', () => { ... } )
* ]
* } );
* ```
*/
export type TemplateValueSchema = ArrayOrItem<TemplateSimpleValueSchema | NamespacedValue<TemplateSimpleValueSchema>> | Record<string, TemplateSimpleValueSchema>;
/**
* Describes an event listener attached to an HTML element. Such listener can propagate DOM events
* through an {@link module:utils/observablemixin~Observable} instance, execute custom callbacks
* or both, if necessary.
*
* Also see:
* * {@link module:ui/template~TemplateDefinition} to learn more about template definitions,
* * {@link module:ui/template~BindChain#to `to()`} method to learn more about bindings.
*
* Check out different ways of attaching event listeners below:
*
* ```ts
* // Bind helper will propagate events through the observable.
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* on: {
* // An object schema. The observable will fire the "clicked" event upon DOM "click".
* click: bind.to( 'clicked' )
*
* // An object schema. It will work for "click" event on "a.foo" children only.
* 'click@a.foo': bind.to( 'clicked' )
*
* // An array schema, makes the observable propagate multiple events.
* click: [
* bind.to( 'clicked' ),
* bind.to( 'executed' )
* ],
*
* // An array schema with a custom callback.
* 'click@a.foo': {
* bind.to( 'clicked' ),
* bind.to( evt => {
* console.log( `${ evt.target } has been clicked!` );
* } }
* }
* }
* } );
* ```
*/
export type TemplateListenerSchema = ArrayOrItem<ListenerBinding>;
declare const AttributeBindingSymbol: unique symbol;
declare const ListenerBindingSymbol: unique symbol;
export interface AttributeBinding {
_opaqueAttributeBinding: typeof AttributeBindingSymbol;
}
export interface ListenerBinding {
_opaqueListenerBinding: typeof ListenerBindingSymbol;
}
/**
* The return value of {@link ~Template.bind `Template.bind()`}. It provides `to()` and `if()`
* methods to create the {@link module:utils/observablemixin~Observable observable} attribute and event bindings.
*/
export interface BindChain<TObservable> {
/**
* Binds an {@link module:utils/observablemixin~Observable observable} to either:
*
* * an HTML element attribute or a text node `textContent`, so it remains in sync with the observable
* attribute as it changes,
* * or an HTML element DOM event, so the DOM events are propagated through an observable.
*
* Some common use cases of `to()` bindings are presented below:
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* attributes: {
* // class="..." attribute gets bound to `observable#a`
* class: bind.to( 'a' )
* },
* children: [
* // <p>...</p> gets bound to observable#b; always `toUpperCase()`.
* {
* text: bind.to( 'b', ( value, node ) => value.toUpperCase() )
* }
* ],
* on: {
* click: [
* // An observable will fire "clicked" upon "click" in the DOM.
* bind.to( 'clicked' ),
*
* // A custom callback will be executed upon "click" in the DOM.
* bind.to( () => {
* ...
* } )
* ]
* }
* } ).render();
* ```
*
* Learn more about using `to()` in the {@link module:ui/template~TemplateValueSchema} and
* {@link module:ui/template~TemplateListenerSchema}.
*
* @label ATTRIBUTE
* @param attribute An attribute name of {@link module:utils/observablemixin~Observable}.
*/
to<TAttribute extends keyof TObservable & string>(attribute: TAttribute): AttributeBinding & ListenerBinding;
/**
* Binds an {@link module:utils/observablemixin~Observable observable} to either:
*
* * an HTML element attribute or a text node `textContent`, so it remains in sync with the observable
* attribute as it changes,
* * or an HTML element DOM event, so the DOM events are propagated through an observable.
*
* Some common use cases of `to()` bindings are presented below:
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* attributes: {
* // class="..." attribute gets bound to `observable#a`
* class: bind.to( 'a' )
* },
* children: [
* // <p>...</p> gets bound to observable#b; always `toUpperCase()`.
* {
* text: bind.to( 'b', ( value, node ) => value.toUpperCase() )
* }
* ],
* on: {
* click: [
* // An observable will fire "clicked" upon "click" in the DOM.
* bind.to( 'clicked' ),
*
* // A custom callback will be executed upon "click" in the DOM.
* bind.to( () => {
* ...
* } )
* ]
* }
* } ).render();
* ```
*
* Learn more about using `to()` in the {@link module:ui/template~TemplateValueSchema} and
* {@link module:ui/template~TemplateListenerSchema}.
*
* @label ATTRIBUTE_CALLBACK
* @param attribute An attribute name of {@link module:utils/observablemixin~Observable}.
* @param callback Allows for processing of the value. Accepts `Node` and `value` as arguments.
*/
to<TAttribute extends keyof TObservable & string>(attribute: TAttribute, callback: (value: TObservable[TAttribute], node: Node) => (TemplateSimpleValue)): AttributeBinding;
/**
* Binds an {@link module:utils/observablemixin~Observable observable} to either:
*
* * an HTML element attribute or a text node `textContent`, so it remains in sync with the observable
* attribute as it changes,
* * or an HTML element DOM event, so the DOM events are propagated through an observable.
*
* Some common use cases of `to()` bindings are presented below:
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'p',
* attributes: {
* // class="..." attribute gets bound to `observable#a`
* class: bind.to( 'a' )
* },
* children: [
* // <p>...</p> gets bound to observable#b; always `toUpperCase()`.
* {
* text: bind.to( 'b', ( value, node ) => value.toUpperCase() )
* }
* ],
* on: {
* click: [
* // An observable will fire "clicked" upon "click" in the DOM.
* bind.to( 'clicked' ),
*
* // A custom callback will be executed upon "click" in the DOM.
* bind.to( () => {
* ...
* } )
* ]
* }
* } ).render();
* ```
*
* Learn more about using `to()` in the {@link module:ui/template~TemplateValueSchema} and
* {@link module:ui/template~TemplateListenerSchema}.
*
* @label EVENT
* @param eventNameOrCallback A DOM event name or an event callback.
*/
to(eventNameOrCallback: string | ((domEvent: Event) => void)): ListenerBinding;
/**
* Binds an {@link module:utils/observablemixin~Observable observable} to an HTML element attribute or a text
* node `textContent` so it remains in sync with the observable attribute as it changes.
*
* Unlike {@link module:ui/template~BindChain#to}, it controls the presence of the attribute or `textContent`
* depending on the "falseness" of an {@link module:utils/observablemixin~Observable} attribute.
*
* ```ts
* const bind = Template.bind( observable, emitter );
*
* new Template( {
* tag: 'input',
* attributes: {
* // <input checked> when `observable#a` is not undefined/null/false/''
* // <input> when `observable#a` is undefined/null/false
* checked: bind.if( 'a' )
* },
* children: [
* {
* // <input>"b-is-not-set"</input> when `observable#b` is undefined/null/false/''
* // <input></input> when `observable#b` is not "falsy"
* text: bind.if( 'b', 'b-is-not-set', ( value, node ) => !value )
* }
* ]
* } ).render();
* ```
*
* Learn more about using `if()` in the {@link module:ui/template~TemplateValueSchema}.
*
* @param attribute An attribute name of {@link module:utils/observablemixin~Observable} used in the binding.
* @param valueIfTrue Value set when the {@link module:utils/observablemixin~Observable} attribute is not
* undefined/null/false/'' (empty string).
* @param callback Allows for processing of the value. Accepts `Node` and `value` as arguments.
*/
if<TAttribute extends keyof TObservable & string>(attribute: TAttribute, valueIfTrue?: unknown, callback?: (value: TObservable[TAttribute], node: Node) => (boolean | FalsyValue)): AttributeBinding;
}
/**
* The {@link module:ui/template~Template#_renderNode} configuration.
*/
export interface RenderData {
/**
* A node which is being rendered.
*/
node: HTMLElement | Text;
/**
* Tells {@link module:ui/template~Template#_renderNode} to render
* children into `DocumentFragment` first and then append the fragment
* to the parent element. It is a speed optimization.
*/
intoFragment: boolean;
/**
* Indicates whether the {@link #node} has been provided by {@link module:ui/template~Template#apply}.
*/
isApplying: boolean;
/**
* An object storing the data that helps {@link module:ui/template~Template#revert}
* bringing back an element to its initial state, i.e. before
* {@link module:ui/template~Template#apply} was called.
*/
revertData?: RevertData;
}
interface RevertData {
text?: string | null;
children: Array<RevertData>;
bindings: Array<Array<() => void>>;
attributes: Record<string, string | null>;
}
export {};