Erreur SQLIte Android: Impossible de lire la ligne 0, la colonne 1 de CursorWindow
J'utilise une base de données slqite préremplie que j'ai créée à l'aide de sqlitebrowser.
J'ai placé le fichier de base de données (il ne semble pas avoir d'extension) dans mon dossier Actifs.
J'utilise la classe standard databasehelper que tout le monde semble utiliser.
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)
Voici ma classe d'assistance de base de données:
Il échoue sur cette ligne dans la classe:
Cursor cursor = db.rawQuery(selectQuery, null);
Voici la classe:
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;
}
}
Les index de colonnes commencent à 0. Votre curseur n'a qu'une colonne. Remplacez donc getString(1) par getString(0) pour accéder à la seule valeur de colonne disponible.
S'il vous plaît, ajoutez après une ligne avant où vous écrivez le code suivant.
if(cursor!=null && cursor.getCount() > 0)
{
if (cursor.moveToFirst())
{
do {
labels.add(cursor.getString(1));
} while (cursor.moveToNext());
}
}
parce que, lorsque le curseur est vide et que vous obtenez une valeur de la part du curseur, son erreur est donnée.
s'il vous plaît essayer de donner des commentaires.
L'augmentation de la version de la base de données a fonctionné pour moi.
mieux vaut utiliser cursor.getColumnIndex() au lieu d’entiers pour obtenir une valeur particulière à partir de Sqlite db comme ci-dessous
if(cursor!=null && cursor.getCount() > 0) {
if (cursor.moveToFirst()) {
do {
labels.add(cursor.getColumnIndex(YOUR_DB_COLUMN_NAME));
} while (cursor.moveToNext());
cursor.close();
}
}