問題onUpdate android

Question

我想在我的數據庫中添加一個新表，而不是更改我已有的其他兩個表。因此，當用戶升級到應用程序時，創建的兩個表將保留並且新的表將被添加到數據庫。所以我這樣做：

private static class toDoDBOpenHelper extends SQLiteOpenHelper { 
    public toDoDBOpenHelper(Context context, String name, 
    CursorFactory factory, int version) { 
    super(context, name, factory, version); 
    } 
    // SQL Statement to create a new database. 
    private static final String DATABASE_CREATE = "create table " + 
    DATABASE_TABLE_1 + " (" + KEY_ID1 + " integer primary key autoincrement, " + 
    CLIENT_NAME + " text not null);"; 

    private static final String DATABASE_CREATE3 = "create table " + 
    DATABASE_TABLE_3 + " (" + KEY_ID3 + " integer primary key autoincrement, " + 
     DESCRIPTION + " text " + LIDER + " text " + GOAL + " text " + 
     PROJECT_ID + " integer);"; 
    @Override 
    public void onCreate(SQLiteDatabase _db) { 
    _db.execSQL(DATABASE_CREATE); 
    _db.execSQL("CREATE TABLE "+DATABASE_TABLE_2+" ("+ KEY_ID2 + " integer primary key autoincrement, "+PROJECT_NAME + " text not null, " + KEY_CREATION_DATE + " long, " +START_TIME +" text, "+ 
      START_DATE+ " text, " + END_TIME + " text, "+ END_DATE + " text, " + 
      TOTAL + " text, "+ CLIENT_ID + " integer);"); 
    _db.execSQL("CREATE TABLE "+DATABASE_TABLE_3+" ("+ KEY_ID3 + " integer primary key autoincrement, "+DESCRIPTION + " text, " + LIDER + " text, " + GOAL +" text, "+ 
      PROJECT_ID + " integer);"); 
    } 
    @Override 
    public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion) { 


    onCreate(_db); 
    } 
    } 

所以我基本上都添加了另一臺在onCreate方法，我在onUpgrade所謂的onCreate。但是，現在在第一次運行該應用程序崩潰的升級換代。該用戶得到這個錯誤後：

java.lang.RuntimeException: Unable to start activity  
ComponentInfo{com.tracking.app/com.tracking.app.Main}: 
android.database.sqlite.SQLiteException: Can't upgrade read-only database from version 
1 to 2: /data/data/com.tracking.app/databases/trackingApp.db 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2787) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2803) 
at android.app.ActivityThread.access$2300(ActivityThread.java:135) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2136) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:144) 
at android.app.ActivityThread.main(ActivityThread.java:4937) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:521) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 
at dalvik.system.NativeStart.main(Native Method) 
Caused by: android.database.sqlite.SQLiteException: Can't upgrade read-only database 
from version 1 to 2: /data/data/com.tracking.app/databases/trackingApp.db 
at 
android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:170) 
at com.tracking.app.ToDoDBAdapter.open(ToDoDBAdapter.java:84) 
at com.tracking.app.Main.onCreate(Main.java:74) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1069) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2751) 
... 11 more 

是否有某事與我的open（）函數？這是代碼：

public void open() throws SQLiteException { 
try { 
db = dbHelper.getWritableDatabase(); 
} catch (SQLiteException ex) { 
db = dbHelper.getReadableDatabase(); 
} 
} 

如果有人有任何想法我做錯了什麼，請讓我儘快知道。感謝ü提前

Answer 1

嘗試只是爲了這個代碼

public void open() throws SQLiteException 
{ 
    try 
    { 
     db = dbHelper.getWritableDatabase(); 
    } 
    catch (SQLiteException ex) 
    { 
    } 
}