license import { TopAppBarBase } from '@material/mwc-top-app-bar/mwc-top-app-bar-base' ; import { passiveEventOptionsIfSupported } from '@material/mwc-top-app-bar/mwc-top-app-bar-base-base' ; import MDCFixedTopAppBarFoundation from '@material/top-app-bar/fixed/foundation' ; export class TopAppBarFixedBase extends TopAppBarBase { protected override mdcFoundation ! : MDCFixedTopAppBarFoundation ; protected override mdcFoundationClass = MDCFixedTopAppBarFoundation ; protected override barClasses ( ) { return { ... super . barClasses ( ) , 'mdc-top-app-bar--fixed' : true , } ; } protected override registerListeners ( ) { this . scrollTarget . addEventListener ( 'scroll' , this . handleTargetScroll , passiveEventOptionsIfSupported ) ; } protected override unregisterListeners ( ) { this . scrollTarget . removeEventListener ( 'scroll' , this . handleTargetScroll ) ; } }