我有这个抽象父类(superclass):publicabstractclassMediaListActivityextendsActivity{...abstractvoidlaunchMedia(MediaFilemediaFile);}和具体的子类:publicclassVideoListActivityextendsMediaListActivity{...voidlaunchMedia(MediaFilemediaFile){//TODO:implementlaunchMedia()}}在VideoListActivity子类的第一行,AndroidStudio报错Class