java - 有人可以帮我处理此消息吗？我尝试创建 ListView ，但运行代码时会弹出此错误

Question

这个问题已经有答案了:

What is a NullPointerException, and how do I fix it? (12 个回答)

已关闭 3 年前。

有人能解决这个错误吗？我尝试制作 ListView ，但运行代码时出现此错误。

错误消息:

2020-02-06 13:40:23.483 16037-16037/com.example.submissionexpert1 E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.submissionexpert1, PID: 16037 java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference at com.example.submissionexpert1.FilmAdapter$ViewHolder.bind(FilmAdapter.java:68) at com.example.submissionexpert1.FilmAdapter.getView(FilmAdapter.java:52)

我的代码:

    import android.content.Context;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.ImageView;
    import android.widget.TextView;
    import java.util.ArrayList;

    class FilmAdapter extends BaseAdapter {


    private final Context context;
    private ArrayList<Film> films = new ArrayList<>();

    void setFilms(ArrayList<Film> films) {
        this.films = films;
    }

    FilmAdapter(Context context) {
        this.context = context;
    }

    @Override
    public int getCount() {
        return films.size();
    }

    @Override
    public Object getItem(int i) {
        return films.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;

    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        View itemView = view;
        if (itemView == null) {
            itemView = LayoutInflater.from(context).inflate(R.layout.item_data, viewGroup, false);
        }

        ViewHolder viewHolder = new ViewHolder(itemView);
    enter code here
        Film film = (Film) getItem(i);
        viewHolder.bind(film);
        return itemView;
    }

    private class ViewHolder {
        private TextView txtName;
        private TextView txtDescription;
        private ImageView imgPhoto;

        ViewHolder(View view) {
            txtName = view.findViewById(R.id.txt_name);
            txtDescription = view.findViewById(R.id.txt_description);
            imgPhoto = view.findViewById(R.id.img_photo);
        }

        void bind(Film film) {
            txtName.setText(film.getNama());
            txtDescription.setText(film.getOverview());
            imgPhoto.setImageResource(film.getPhoto());
        }
    }
}

Answer 1

请检查以下两个返回 null 或对象的字段并进行相应更正。可能是您访问了错误的 TextView ID。

txtName = view.findViewById(R.id.txt_name); // may return null
txtDescription = view.findViewById(R.id.txt_description); // // may return null

希望这有帮助。