光標多次返回第1行

Question

我試圖讓我的數據庫的內容出現在ListView中。有一些錯誤（很明顯），它多次返回數據庫中的第1行。

例如，如果有2行，它將返回行＃1 2次。如果我添加另一條記錄，它將返回行＃1 3次。

這裏是我的history.java

... 
MySQLiteHelper db = new MySQLiteHelper(this); 

Cursor cursor = db.getAllLogs(); 
Log.d("history.java", "finished Cursor cursor = db.getAllLogs();"); 
GasCursorAdapter adapter = new GasCursorAdapter(this, cursor, 0); 
Log.d("history.java", "GasCursorAdapter adapter = new GasCursorAdapter(this, cursor, 0);"); 
listContent.setAdapter(adapter); 
Log.d("history.java", "setAdapter(adapter);"); 

，這裏是我的MySQLiteHelper.java

... 
public Cursor getAllLogs() {  
    List<String> List = new ArrayList<String>(); 

    String selectQuery = "SELECT * FROM " + TABLE_GASLOG; 

    SQLiteDatabase db = this.getWritableDatabase(); 

    Cursor cursor = db.rawQuery(selectQuery, null); 

    return cursor; 
} 

我猜這件事情，我需要在getAllLogs()做...但我不能指出它。我嘗試過使用cursor.moveToFirst()和moveToNext，但這似乎產生了相同的結果......似乎知道有多個記錄，但只是多次返回第一個！

任何幫助，非常感謝！

EDIT（附加信息） newRecord.java

public class newRecord extends Activity { 

String fill; 

protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.new_record); 
    Typeface tf = Typeface.createFromAsset(getAssets(),"Roboto-Light.ttf"); 


    final MySQLiteHelper db = new MySQLiteHelper(this); 

    final EditText pricePerGallon = (EditText) findViewById(R.id.pricePerGallon); 
    final EditText gallons = (EditText) findViewById(R.id.gallons); 
    final EditText odometer = (EditText) findViewById(R.id.odometer); 
    final EditText today = (EditText) findViewById(R.id.date); 
    final EditText comments = (EditText) findViewById(R.id.comments); 
    final CheckBox notCompleteFill = (CheckBox) findViewById(R.id.completeFill); 
    TextView save = (TextView) findViewById(R.id.save); 
    TextView reset = (TextView) findViewById(R.id.reset); 
    pricePerGallon.setTypeface(tf); 
    gallons.setTypeface(tf); 
    odometer.setTypeface(tf); 
    today.setTypeface(tf); 
    comments.setTypeface(tf); 
    notCompleteFill.setTypeface(tf); 
    save.setTypeface(tf); 
    reset.setTypeface(tf); 

    SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy"); 
    today.setText(sdf.format(new Date())); 

    save.setOnClickListener(new OnClickListener() { 
     @Override 
     public void onClick(View v){ 
      String pricePerGallonString = pricePerGallon.getText().toString(); 
      final double pricePerGallonInt = Double.parseDouble(pricePerGallonString); 
      String gallonsString = gallons.getText().toString(); 
      final double gallonsInt = Double.parseDouble(gallonsString); 
      String odometerString = odometer.getText().toString(); 
      final double odometerInt = Double.parseDouble(odometerString); 
      String todayString = today.getText().toString(); 
      String notCompleteFillString = notCompleteFill.getText().toString(); 
      String commentsString = comments.getText().toString(); 

      db.addGasLog(new gasLog(pricePerGallonInt, gallonsInt, odometerInt, todayString, fill, commentsString)); 
      Toast.makeText(getApplicationContext(), "Data Saved", Toast.LENGTH_LONG).show(); 
      Intent i = new Intent(newRecord.this, history.class); 
      startActivity(i); 
     } 
    }); 

MySQLiteHelper.java

public void addGasLog(gasLog gasLog){ 
     // for logging 
     Log.d("addGasLog", gasLog.toString()); 

     // 1. get reference to writable DB 
     SQLiteDatabase db = this.getWritableDatabase(); 

     // 2. create ContentValues to add key "column"/value 
     ContentValues values = new ContentValues(); 
     values.put(KEY_PRICE_PER_GALLON, gasLog.getPricePerGallon()); // get price 
     values.put(KEY_GALLONS, gasLog.getGallons()); // get gallons 
     values.put(KEY_ODOMETER, gasLog.getOdometer()); // get odometer 
     values.put(KEY_DATE, gasLog.getDate()); // get date 
     values.put(KEY_FILLED_OR_NOT, gasLog.getFilledOrNot()); // get filledOrNot 
     values.put(KEY_COMMENTS, gasLog.getComments()); // get comments 

     // 3. insert 
     db.insert(TABLE_GASLOG, //table 
       null, //nullColumnHack 
       values); // key/value -> keys = column names/ values = 

     // 4. Close 
     db.close(); 
    } 

EDIT2 GasCursorAdapter.java

import android.content.Context; 
import android.content.Intent; 
import android.database.Cursor; 
import android.support.v4.widget.CursorAdapter; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.view.ViewGroup; 
import android.widget.TextView; 

public class GasCursorAdapter extends CursorAdapter { 


    //private LayoutInflater mInflater = null; 

    public GasCursorAdapter(Context context, Cursor c, int flags){ 
     super(context, c, flags); 
     //mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     Log.d("inGasCursorAdapter", "GasCursorAdapter"); 
    } 

    @Override 
    public View newView(Context context, Cursor cursor, ViewGroup parent){ 
     LayoutInflater inflater = LayoutInflater.from(parent.getContext()); 
     View retView = inflater.inflate(R.layout.card_background, parent, false); 
     Log.d("inGasCursorAdapter", "newView"); 
     return retView; 
     //return mInflater.inflate(R.layout.card_background, parent, false); 
    } 

    @Override 
    public void bindView(View v, Context context, Cursor cursor){ 
     /* 
     * cardDate 
     * cardGallons 
     * cardPrice 
     * cardMPG 
     */ 

     TextView cardDate = (TextView) v.findViewById(R.id.cardDate); 
     int date = cursor.getColumnIndexOrThrow(MySQLiteHelper.KEY_DATE); 
     cardDate.setText(Integer.toString(date)); 

     TextView cardGallons = (TextView) v.findViewById(R.id.cardGallons); 
     int gallons = cursor.getColumnIndexOrThrow(MySQLiteHelper.KEY_GALLONS); 
     cardGallons.setText(Integer.toString(gallons) + "gal"); 

     TextView cardPrice = (TextView) v.findViewById(R.id.cardPrice); 
     int price = cursor.getColumnIndexOrThrow(MySQLiteHelper.KEY_PRICE_PER_GALLON); 
     cardPrice.setText("$" + Integer.toString(price)); 

     TextView cardMPG = (TextView) v.findViewById(R.id.cardMPG); 
     int MPG = cursor.getColumnIndexOrThrow(MySQLiteHelper.KEY_ODOMETER); 
     cardMPG.setText(Integer.toString(MPG)); 

     TextView cardDelete = (TextView) v.findViewById(R.id.cardDelete); 
     cardDelete.setOnClickListener(new OnClickListener() { 
      @Override 
      public void onClick(View v){ 

      } 
     }); 


    } 

} 

Answer 1

您的表是否有名爲_id的列？如果不是，您可能需要選擇單個列（您應該執行這些操作（而不是選擇*），並將您的密鑰主鍵別名爲_id。