export interface TrackItem { id ? : string ; name ? : string ; artist ? : string ; image ? : string ; available : boolean ; } export default class Track implements TrackItem { name ? : string ; artist ? : string ; image ? : string ; available : boolean ; constructor ( trackItem ) { this . name = trackItem . name ; this . artist = trackItem . artist ; this . image = trackItem . image ; this . available = trackItem . available ; } }