import { IPropertyPaneField } from "@microsoft/sp-property-pane" ; import { WebPartContext } from '@microsoft/sp-webpart-base' ; export interface ILayout { /**
     * The Web Part properties in the property bag. Corresponds to the isolated 'layoutProperties' property in the global property bag.
     */ properties : any ; /**
     * Context of the main Web Part
     */ context : WebPartContext ; /**
     * Method called during the Web Part initialization.
     */ onInit ( ) : void | Promise < void > ; param availableFields getPropertyPaneFieldsConfiguration ( availableFields ) : IPropertyPaneField < any > [ ] ; param propertyPath param oldValue param newValue onPropertyUpdate ( propertyPath , oldValue , newValue ) : void ; }