打电话超级投掷"超级不是表达"

Question

我从这里开始学习从Google指南实施MVVM:https: //codelabs.developers.google.com/codelabs/android-room-with-a-view/#8 (特别是对我感兴趣的页面发布链接) .
由于我理解在Java中实现它,我决定切换到Kotlin.在类扩展中初始化构造函数时,AndroidViewModel我需要调用super它,它会抛出以下错误:

"super"不是表达,它只能用在点的左侧('.')"

当我用Google搜索并发现类似的主题但我根本不理解它,所以我没有解决我的问题.这是我的ViewModel课程代码:

 class NotesViewModel private constructor(application: Application) : AndroidViewModel(application){

    var mRepository: NotesRepository? = null
    var mAllNotes: LiveData<List<Notes>>? = null

    init {
        super(application) // <-- here it throws me an error
        mRepository = NotesRepository(application)
        mAllNotes = mRepository!!.getAllWords()
    }

    fun getAllNotes(): LiveData<List<Notes>>{
        return mAllNotes!!
    }

    fun insert(notes: Notes){
        mRepository!!.insert(notes)
    }

}

那么,我该如何正确调用super,构造一个构造函数呢？这是这个类的正确java代码:

public class WordViewModel extends AndroidViewModel {

  private WordRepository mRepository;
    private LiveData<List<Word>> mAllWords;

    public WordViewModel(Application application) {
        super(application);
        mRepository = new WordRepository(application);
        mAllWords = mRepository.getAllWords();
    }

    LiveData<List<Word>> getAllWords() {
        return mAllWords;
    }

    void insert(Word word) {
        mRepository.insert(word);
    }
}

Answer 1

你已经在这里打电子了: NotesViewModel private constructor(application: Application) : AndroidViewModel(application)

另一个问题是你的构造函数是 private

只需制作public并删除super来电即可init()