2014-05-09 10 views
12

nicht lesen Ich verwende eine preplopulated slqite Datenbank, die ich mit sqlitebrowser erstellte.Android SQLIte-Fehler: Konnte Reihe 0, Spalte 1 von CursorWindow

Ich habe die Datenbankdatei (es scheint keine Erweiterung zu haben) in meinen Assets-Ordner gelegt.

Ich verwende die Standard-Datenbankhelfer-Klasse, die jeder zu verwenden scheint.

05-09 13:04:55.746  894-894/com.myapp.myappname E/CursorWindow﹕ Failed to read row 0, column 1 from a CursorWindow which has 19 rows, 1 columns. 
05-09 13:04:55.766  894-894/com.myapp.myappname D/AndroidRuntime﹕ Shutting down VM 
05-09 13:04:55.766  894-894/com.myapp.myappname W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x40a71930) 
05-09 13:04:55.876  894-894/com.myapp.myappname E/AndroidRuntime﹕ FATAL EXCEPTION: main 
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myapp.myappname/com.myapp.myappname.MainActivity}: java.lang.IllegalStateException: Couldn't read row 0, col 1 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it. 
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180) 
      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230) 
      at android.app.ActivityThread.access$600(ActivityThread.java:141) 
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
      at android.os.Handler.dispatchMessage(Handler.java:99) 
      at android.os.Looper.loop(Looper.java:137) 
      at android.app.ActivityThread.main(ActivityThread.java:5041) 
      at java.lang.reflect.Method.invokeNative(Native Method) 
      at java.lang.reflect.Method.invoke(Method.java:511) 
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
      at dalvik.system.NativeStart.main(Native Method) 
    Caused by: java.lang.IllegalStateException: Couldn't read row 0, col 1 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it. 
      at android.database.CursorWindow.nativeGetString(Native Method) 
      at android.database.CursorWindow.getString(CursorWindow.java:434) 
      at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51) 
      at com.myapp.myappname.DataBaseHelper.getAllOccasions(DataBaseHelper.java:193) 
      at com.myapp.myappname.MainActivity.loadOccasionSpinnerData(MainActivity.java:155) 
      at com.myapp.myappname.MainActivity.onCreate(MainActivity.java:72) 
      at android.app.Activity.performCreate(Activity.java:5104) 
      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080) 
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144) 
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230) 
            at android.app.ActivityThread.access$600(ActivityThread.java:141) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
            at android.os.Handler.dispatchMessage(Handler.java:99) 
            at android.os.Looper.loop(Looper.java:137) 
            at android.app.ActivityThread.main(ActivityThread.java:5041) 
            at java.lang.reflect.Method.invokeNative(Native Method) 
            at java.lang.reflect.Method.invoke(Method.java:511) 
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
            at dalvik.system.NativeStart.main(Native Method) 

Hier ist meine Datenbank Hilfsklasse:

es auf dieser Linie in der Klasse nicht:

import android.content.Context; 
import android.database.Cursor; 
import android.database.SQLException; 
import android.database.sqlite.SQLiteDatabase; 
import android.database.sqlite.SQLiteException; 
import android.database.sqlite.SQLiteOpenHelper; 

import java.io.FileOutputStream; 
import java.io.IOException; 

import android.content.Context; 
import android.database.sqlite.SQLiteDatabase; 
import android.database.sqlite.SQLiteOpenHelper; 

import java.io.IOException; 
import java.io.InputStream; 
import java.io.OutputStream; 
import java.util.ArrayList; 
import java.util.List; 


public class DataBaseHelper extends SQLiteOpenHelper { 

    //The Android's default system path of your application database. 
    private static String DB_PATH = "/data/data/com.myapp.myappname/databases/"; 

    private static String DB_NAME = "WTWDatabase"; 

    private SQLiteDatabase myDataBase; 

    private final Context myContext; 

    /** 
    * Constructor 
    * Takes and keeps a reference of the passed context in order to access to the application assets and resources. 
    * @param context 
    */ 
    public DataBaseHelper(Context context) { 

     super(context, DB_NAME, null, 1); 
     if(android.os.Build.VERSION.SDK_INT >= 17){ 
      DB_PATH = context.getApplicationInfo().dataDir + "/databases/"; 
     } 
     else 
     { 
      DB_PATH = "/data/data/" + context.getPackageName() + "/databases/"; 
     } 

     this.myContext = context; 
    } 

    /** 
    * Creates a empty database on the system and rewrites it with your own database. 
    * */ 
    public void createDataBase() throws IOException { 

     boolean dbExist = checkDataBase(); 

     if(dbExist){ 
      //do nothing - database already exist 
     }else{ 

      //By calling this method and empty database will be created into the default system path 
      //of your application so we are gonna be able to overwrite that database with our database. 
      this.getReadableDatabase(); 

      try { 

       copyDataBase(); 

      } catch (IOException e) { 

       throw new Error("Error copying database"); 

      } 
     } 

    } 

    /** 
    * Check if the database already exist to avoid re-copying the file each time you open the application. 
    * @return true if it exists, false if it doesn't 
    */ 
    private boolean checkDataBase(){ 

     SQLiteDatabase checkDB = null; 

     try{ 
      String myPath = DB_PATH + DB_NAME; 
      checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); 

     }catch(SQLiteException e){ 

      //database does't exist yet. 

     } 

     if(checkDB != null){ 

      checkDB.close(); 

     } 

     return checkDB != null ? true : false; 
    } 

    /** 
    * Copies your database from your local assets-folder to the just created empty database in the 
    * system folder, from where it can be accessed and handled. 
    * This is done by transfering bytestream. 
    * */ 
    private void copyDataBase() throws IOException{ 

     //Open your local db as the input stream 
     InputStream myInput = myContext.getAssets().open(DB_NAME); 

     // Path to the just created empty db 
     String outFileName = DB_PATH + DB_NAME; 

     //Open the empty db as the output stream 
     OutputStream myOutput = new FileOutputStream(outFileName); 

     //transfer bytes from the inputfile to the outputfile 
     byte[] buffer = new byte[1024]; 
     int length; 
     while ((length = myInput.read(buffer))>0){ 
      myOutput.write(buffer, 0, length); 
     } 

     //Close the streams 
     myOutput.flush(); 
     myOutput.close(); 
     myInput.close(); 

    } 

    public void openDataBase() throws SQLException { 

     //Open the database 
     String myPath = DB_PATH + DB_NAME; 
     myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); 

    } 

    @Override 
    public synchronized void close() { 

     if(myDataBase != null) 
      myDataBase.close(); 

     super.close(); 

    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 

    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 

    } 

    // Add your public helper methods to access and get content from the database. 
    // You could return cursors by doing "return myDataBase.query(....)" so it'd be easy 
    // to you to create adapters for your views. 
    /** 
    * Getting all labels 
    * returns list of labels 
    * */ 
    public List<String> getAllOccasions(){ 
     List<String> labels = new ArrayList<String>(); 

     // Select All Query 
     String selectQuery = "SELECT Occasion FROM Occasions"; 

     SQLiteDatabase db = this.getReadableDatabase(); 
     Cursor cursor = db.rawQuery(selectQuery, null); //FAILS HERE 

     // looping through all rows and adding to list 
     if (cursor.moveToFirst()) { 
      do { 
       labels.add(cursor.getString(1)); 
      } while (cursor.moveToNext()); 
     } 

     // closing connection 
     cursor.close(); 
     db.close(); 

     // returning lables 
     return labels; 
    } 

    public List<String> getAllSubCategories(String Occasion){ 
     List<String> labels = new ArrayList<String>(); 

     // Select All Query 
     String selectQuery = "Select subcategory from subcategory where Occasionkey = (select _id from Occasions where Occasion = '" + Occasion + "')"; 

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

     // looping through all rows and adding to list 
     if (cursor.moveToFirst()) { 
      do { 
       labels.add(cursor.getString(1)); 
      } while (cursor.moveToNext()); 
     } 

     // closing connection 
     cursor.close(); 
     db.close(); 

     // returning lables 
     return labels; 
    } 


    public List<String> getAllMessages(String Occasion, String SubCategory){ 
     List<String> labels = new ArrayList<String>(); 

     // Select All Query 
     String selectQuery = "Select Message from Messages INNER JOIN\n" + 
       "MessageSubCategory ON MessageSubCategory.MessageKey = Messages._id\n" + 
       " where Messages.OccasionKey = (select _id from Occasions where Occasion = '\" + Occasion + \"')\n" + 
       "AND MessageSubCategory.SubCategoryKey = (select SubCategory._id from SubCategory where SubCategory.Subcategory = '\" + SubCategory + \"')"; 

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

     // looping through all rows and adding to list 
     if (cursor.moveToFirst()) { 
      do { 
       labels.add(cursor.getString(1)); 
      } while (cursor.moveToNext()); 
     } 

     // closing connection 
     cursor.close(); 
     db.close(); 

     // returning lables 
     return labels; 
    } 

} 

Antwort

25

Spalte Indizes ab:

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

Hier ist die Klasse 0. Ihr Cursor hat nur 1 Spalte, also ersetzen Sie getString(1) durch getString(0) nach acc Es ist der einzige Spaltenwert.

+0

das hat funktioniert! groß! – user3437721

1

Bitte fügen Sie die folgende Zeile vor dem folgenden Code hinzu.

weil, wenn der Cursor leer ist und Sie Wert vom Cursor erhalten, geben Sie einen Fehler.

Bitte versuchen Sie es und geben Sie Feedback.

0

Zunehmende Datenbankversion funktionierte für mich.

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