ipsos-components
Version:
Material Design components for Angular
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text/typescript
/**
* @license
* Copyright Google LLC All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {ListKeyManager, ListKeyManagerOption} from './list-key-manager';
/**
* This is the interface for highlightable items (used by the ActiveDescendantKeyManager).
* Each item must know how to style itself as active or inactive and whether or not it is
* currently disabled.
*/
export interface Highlightable extends ListKeyManagerOption {
/** Applies the styles for an active item to this item. */
setActiveStyles(): void;
/** Applies the styles for an inactive item to this item. */
setInactiveStyles(): void;
}
export class ActiveDescendantKeyManager<T> extends ListKeyManager<Highlightable & T> {
/**
* This method sets the active item to the item at the specified index.
* It also adds active styles to the newly active item and removes active
* styles from the previously active item.
*/
setActiveItem(index: number): void {
if (this.activeItem) {
this.activeItem.setInactiveStyles();
}
super.setActiveItem(index);
if (this.activeItem) {
this.activeItem.setActiveStyles();
}
}
}