| /** | 
 |  * @license | 
 |  * Copyright 2020 Google LLC | 
 |  * SPDX-License-Identifier: Apache-2.0 | 
 |  */ | 
 |  | 
 | export declare interface PopupPluginApi { | 
 |   /** | 
 |    * Opens the popup, inserts it into the DOM over current UI. | 
 |    * Creates the popup if not previously created. Creates and inserts the popup | 
 |    * content element, if a `moduleName` was provided in the constructor. | 
 |    * Otherwise you have to call `appendContent()` when the promise resolves. | 
 |    */ | 
 |   open(): Promise<PopupPluginApi>; | 
 |  | 
 |   /** | 
 |    * Hides the popup. | 
 |    */ | 
 |   close(): void; | 
 |  | 
 |   /** | 
 |    * Appends the given element as a child to the popup. Only call this method | 
 |    * when you have called `popup()` without a `moduleName`. | 
 |    */ | 
 |   appendContent(el: HTMLElement): void; | 
 | } |