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POandroid database, reading from file
 

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    <p>i am new in eclipse and android programming, i have a problem with my database connection. Well i found many links and well i post my 2 classes. If someone can find the mistake. The database i have is made with sqlite and it has that android_metadata and a questions table. When i run in emulator it have some messages when i open the About form "The application Quiz Test by DrymVyzion (process dv.qtest.dvyzual) has stoped unexpectedly. Please try again." At eclipse that's the errors:</p> <pre><code>01-08 22:50:42.292: E/AndroidRuntime(1059): Uncaught handler: thread main exiting due to uncaught exception 01-08 22:50:42.312: E/AndroidRuntime(1059): java.lang.RuntimeException: Unable to start activity ComponentInfo{dv.qtest.dvyzual/dv.qtest.dvyzual.About}: android.database.sqlite.SQLiteException: no such table: questions: , while compiling: SELECT _id, question, qone, qtwo, qthree, qanswer FROM questions 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread.access$2100(ActivityThread.java:116) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.os.Handler.dispatchMessage(Handler.java:99) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.os.Looper.loop(Looper.java:123) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread.main(ActivityThread.java:4203) 01-08 22:50:42.312: E/AndroidRuntime(1059): at java.lang.reflect.Method.invokeNative(Native Method) 01-08 22:50:42.312: E/AndroidRuntime(1059): at java.lang.reflect.Method.invoke(Method.java:521) 01-08 22:50:42.312: E/AndroidRuntime(1059): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 01-08 22:50:42.312: E/AndroidRuntime(1059): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 01-08 22:50:42.312: E/AndroidRuntime(1059): at dalvik.system.NativeStart.main(Native Method) 01-08 22:50:42.312: E/AndroidRuntime(1059): Caused by: android.database.sqlite.SQLiteException: no such table: questions: , while compiling: SELECT _id, question, qone, qtwo, qthree, qanswer FROM questions 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteProgram.native_compile(Native Method) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteProgram.compile(SQLiteProgram.java:110) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteProgram.&lt;init&gt;(SQLiteProgram.java:59) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteQuery.&lt;init&gt;(SQLiteQuery.java:49) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:49) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1118) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1006) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:964) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1041) 01-08 22:50:42.312: E/AndroidRuntime(1059): at dv.qtest.dvyzual.About.getEvents(About.java:46) 01-08 22:50:42.312: E/AndroidRuntime(1059): at dv.qtest.dvyzual.About.onCreate(About.java:22) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123) 01-08 22:50:42.312: E/AndroidRuntime(1059): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364) </code></pre> <p>Here are my two classes:</p> <p><strong>quizData.java</strong></p> <pre><code>package dv.qtest.dvyzual; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; 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; /** Helper to the database, manages versions and creation */ public class quizData extends SQLiteOpenHelper { private static final String DB_PATH = "/data/data/dv.qtest.dvyzual/databases/"; private static final String DB_NAME = "q.db"; private static final int DATABASE_VERSION = 1; private SQLiteDatabase myDataBase; private final Context myContext; // Table name public static final String TABLE = "questions"; // Columns public static final String qid = "_id"; public static final String question = "question"; public static final String qone = "qone"; public static final String qtwo = "qtwo"; public static final String qthree = "qthree"; public static final String qanswer = "qanswer"; public quizData(Context context) { super(context, DB_NAME, null, DATABASE_VERSION); this.myContext = context; } public void createDataBase() throws IOException{ boolean dbExist = checkDataBase(); if(dbExist){ }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 { this.close(); // testing 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))&gt;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) { } } </code></pre> <p><strong>About.java</strong></p> <pre><code>package dv.qtest.dvyzual; import java.io.IOException; import android.app.Activity; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.widget.TextView; public class About extends Activity { /** Called when the activity is first created. */ private quizData eventsData = new quizData(About.this); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.about); Cursor cursor = getEvents(); showEvents(cursor); try { eventsData.createDataBase(); } catch (IOException ioe) { throw new Error("Unable to create database"); } try { eventsData.openDataBase(); }catch(SQLException sqle){ throw sqle; } } @Override public void onDestroy() { eventsData.close(); } private Cursor getEvents() { SQLiteDatabase db = eventsData.getReadableDatabase(); Cursor cursor = db.query("questions", new String[]{"_id","question","qone", "qtwo", "qthree", "qanswer"}, null, null, null, null, null); startManagingCursor(cursor); return cursor; } private void showEvents(Cursor cursor) { StringBuilder ret = new StringBuilder("Saved Events:\n\n"); while (cursor.moveToNext()) { long id = cursor.getLong(0); String q = cursor.getString(1); String q1 = cursor.getString(2); ret.append(id + ": " + q + ": " + q1 + "\n"); } TextView tv = new TextView(this); tv.setText(ret); setContentView(tv); } } </code></pre> <p>Please help if someone can find what i do wrong, i am trying that many hours! By the way it works for databases not from file without DB path. So maybe the problem is that i didn't setup the db helper correcty? Any ideas?</p>
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