Java SQLite列“\u id”不存在

应用程序：我有一个应用程序，可以创建多台机器，其中包括：

id、名称和位置 每台机器我都要让用户输入收入

身份证、票据、日期、货币、机器 问题：java.lang.IllegalArgumentException:列'\u id'不存在，而在DBHelper中显然存在

我尝试过：卸载应用程序，用ADM删除DB，升级DB版本

我的问题：我错过了什么

如果你需要任何其他课程或有任何反馈，请毫不犹豫地放纵我

数据库助手

列表适配器

错误

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正如Javadoc所述：

游标必须包含名为_id的列，否则此类将不会 工作

因此，必须将_id添加到投影中，以便生成的光标将具有该列。例如：

    Cursor cursor = db.rawQuery("SELECT _id, note, date FROM income WHERE machines_id = "+machinesId+"", null);

---

可能重复为什么它是重复的？你能详述你的声明吗？

public class MachineInfo extends AppCompatActivity {

private TextView mLocation, mMoney, mNotes;
private DBHelpter mDBHelpter;
private ListView mNotesList;
private FloatingActionButton mFAB;
private SQLiteDatabase db;
private Cursor mCursor;

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

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    mDBHelpter = new DBHelpter(getApplicationContext());
    db = mDBHelpter.getWritableDatabase();

    mLocation = (TextView) findViewById(R.id.tvLocation);
    mMoney = (TextView) findViewById(R.id.tvMoney);
    mNotes = (TextView) findViewById(R.id.tvNotes);
    mFAB = (FloatingActionButton) findViewById(R.id.fabAddIncome);
    mNotesList = (ListView) findViewById(R.id.lvNotes);

    SharedPreferences mSharedPreferences = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
    Long machines_id = mSharedPreferences.getLong("machines_id", 0);

    double total_amount = mDBHelpter.getIncomeOfMachine(machines_id);
    mMoney.setText(String.format("%.3f",total_amount));

    String location = mSharedPreferences.getString("location", null);
    mLocation.setText(location);

    mCursor = db.rawQuery("SELECT note, date FROM income WHERE machines_id = "+machines_id+"",null);
    ListAdapter adapter = new ListAdapter(this, mCursor);
    mNotesList.setAdapter(adapter);
    db.close();

    mFAB.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent i = new Intent(getApplicationContext(), IncomeCreation.class);
            startActivity(i);
        }
    });

}

public class ListAdapter extends CursorAdapter {


public ListAdapter(Context context, Cursor c) {
    super(context, c);
}

public View newView(Context context, Cursor cursor, ViewGroup parent) {
    return LayoutInflater.from(context).inflate(R.layout.notes_list, parent, false);
}

@Override
public void bindView(View view, Context context, Cursor cursor) {

    DBHelpter mDBHelper = new DBHelpter(context);
    SQLiteDatabase db = mDBHelper.getWritableDatabase();

    TextView mNote = (TextView) view.findViewById(R.id.tvNote);
    TextView mNotesDate = (TextView) view.findViewById(R.id.tvNoteDate);

    String note = cursor.getString(cursor.getColumnIndex("note"));
    String date = cursor.getString(cursor.getColumnIndex("date"));

    mNote.setText(note);
    mNotesDate.setText(date);

}

 java.lang.RuntimeException: Unable to start activity ComponentInfo{tech.destinum.machines/tech.destinum.machines.MachineInfo}: java.lang.IllegalArgumentException: column '_id' does not exist
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
      at android.app.ActivityThread.-wrap11(ActivityThread.java)
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
      at android.os.Handler.dispatchMessage(Handler.java:102)
      at android.os.Looper.loop(Looper.java:148)
      at android.app.ActivityThread.main(ActivityThread.java:5417)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
   Caused by: java.lang.IllegalArgumentException: column '_id' does not exist
      at android.database.AbstractCursor.getColumnIndexOrThrow(AbstractCursor.java:333)
      at android.widget.CursorAdapter.init(CursorAdapter.java:180)
      at android.widget.CursorAdapter.<init>(CursorAdapter.java:128)
      at tech.destinum.machines.ListAdapter.<init>(ListAdapter.java:0)
      at tech.destinum.machines.MachineInfo.onCreate(MachineInfo.java:62)
      at android.app.Activity.performCreate(Activity.java:6237)
      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
      at android.app.ActivityThread.-wrap11(ActivityThread.java) 
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
      at android.os.Handler.dispatchMessage(Handler.java:102) 
      at android.os.Looper.loop(Looper.java:148) 
      at android.app.ActivityThread.main(ActivityThread.java:5417) 
      at java.lang.reflect.Method.invoke(Native Method) 
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 

    Cursor cursor = db.rawQuery("SELECT _id, note, date FROM income WHERE machines_id = "+machinesId+"", null);