当我进入回收者视图活动时，我的应用程序崩溃

Question

我正在开发一个输入表单应用程序，它具有一个主菜单，一个数据输入表单和一个显示表单，以显示添加到数据库中的所有项目，我正在使用android Room库。

当我按下主菜单中的“查看塔”按钮时，我的应用程序崩溃了，但是只有在加载应用程序后首先按下它时，我的应用程序才会崩溃。我认为这与我将字数据库值设置为NonNull有关，但是我需要这样做以避免将空值添加到表中。我已经厌倦了调试它，但似乎找不到与之相关的错误，调试器可以正常运行，直到到达“ super.onResume（）;”为止。行暂停一秒钟，然后应用崩溃。

任何帮助将不胜感激。

谢谢

我的onCreate方法：

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RecyclerView recyclerView = findViewById(R.id.RecyclerView);
        final WordListAdapter adapter = new WordListAdapter(this);
        recyclerView.setAdapter(adapter);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));

        mWordViewModel = ViewModelProviders.of(this).get(WordViewModel.class);
        try {
            mWordViewModel.getAllWords().observe(this, new Observer<List<Word>>() {
                @Override
                public void onChanged(List<Word> words) {
                    try {
                        adapter.setWords(words);
                    } catch (Exception e) {
                        Log.d("SET WORDS FAIL", e.toString());
                    }
                }
            });
        } catch (Exception e) {
            Log.d("GET ALL WORD FAIL", e.toString());
        }

我的onResume方法：

@Override
    protected void onResume() {
        super.onResume();
        try {
            Word word = new Word(getIntent().getStringExtra(EXTRA_REPLY));
            mWordViewModel.insert(word);
        } catch (Exception e) {
            Log.d("ON REUSME FAIL", e.toString());
        }
    }

My ViewModel:

public class WordViewModel extends AndroidViewModel {
    private WordRepository repository;
    private LiveData<List<Word>> allWords;

    public WordViewModel (Application application) {
        super(application);
        repository = new WordRepository(application);
        allWords = repository.getAllWords();
    }

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

    public void insert(Word word) {
        repository.insert(word);
    }
}

我的回忆录：

public class WordRepository {
    private WordDAO mWordDao;
    private LiveData<List<Word>> allWords;

    WordRepository(Application application) {
        WordRoomDataBase db = WordRoomDataBase.getDataBase(application);
        mWordDao = db.wordDAO();
        allWords = db.wordDAO().getAllWords();
    }

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

    public void insert (Word word) {
        new insertAsyncTask(mWordDao).execute(word);
    }

    private static class insertAsyncTask extends AsyncTask<Word, Void, Void> {
        private WordDAO mAsyncTaskDAO;

        insertAsyncTask(WordDAO dao) {
            mAsyncTaskDAO = dao;
        }

        @Override
        protected Void doInBackground(final Word... words) {
            mAsyncTaskDAO.insert(words[0]);
            return null;
        }
    }
}

我的数据访问对象：

@Dao
public interface WordDAO {

    @Insert
    void insert(Word word);

    @Query("DELETE FROM word_table")
    void deleteAll();

    @Query("SELECT * from word_table ORDER BY word ASC")
    LiveData<List<Word>> getAllWords();
}

我的对象：

@Entity(tableName = "word_table")
public class Word {

    @ColumnInfo(name = "word")
    @NonNull
    @PrimaryKey
    private String Word;

    public Word(String Word) {
        this.Word = Word;
    }

    public String getWord() {
        return this.Word;
    }
}

我的RecyclerView适配器：

public class WordListAdapter extends RecyclerView.Adapter<WordListAdapter.WordViewHolder> {

    class WordViewHolder extends RecyclerView.ViewHolder {
        private final TextView wordItemView;

        private WordViewHolder(View itemView) {
            super(itemView);
            wordItemView = itemView.findViewById(R.id.RecyclerViewTextView);
        }
    }

    private final LayoutInflater mInflator;
    private List<Word> mWords;

    WordListAdapter(Context context) {
        mInflator = LayoutInflater.from(context);
    }

    @NonNull
    @Override
    public WordViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View itemView = mInflator.inflate(R.layout.recycler_view_item, parent, false);
        return new WordViewHolder(itemView);
    }

    @Override
    public void onBindViewHolder(@NonNull WordViewHolder holder, int position) {
        if (mWords != null) {
            Word current = mWords.get(position);
            holder.wordItemView.setText(current.getWord());
        } else {
            holder.wordItemView.setText("No Words");
        }
    }

    @Override
    public int getItemCount() {
        if (mWords != null) {
            return mWords.size();
        } else return 0;
    }

    void setWords(List<Word> words) {
        mWords = words;
        notifyDataSetChanged();
    }


}