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PODatabase Lock NPE
 

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    <p>I was wondering if you could help me with this error I'm getting...</p> <h2>Source Code:</h2> <p>Main.java:</p> <pre><code>public class Main extends Activity { protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); context = this; DBAdapter dbA = new DBAdapter(context); dbA.open(); // error at this statement // [....] } } </code></pre> <p>DBAdapter.java</p> <pre><code>public class DBAdapter { Context context; DatabaseHelper DBHelper; SQLiteDatabase db; public DBAdapter(Context ctx) { this.context = ctx; DBHelper = new DatabaseHelper(context); } private static final class DatabaseHelper extends SQLiteOpenHelper { private static Context context; DatabaseHelper(Context ctx) { super(context, DATABASE_NAME, null, DATABASE_VERSION); context = ctx; } onCreate(SQLiteDatabase db) // this line of code is never reached [...] // {...} onUpgradeonUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) // neither is this one [...] // {...} } // ---opens the database--- public DBAdapter open() throws SQLException { db = DBHelper.getWritableDatabase(); // error at this statement return this; } // [...] } </code></pre> <h2>LogCat</h2> <pre><code>03-10 00:09:15.061: E/AndroidRuntime(5668): FATAL EXCEPTION: main 03-10 00:09:15.061: E/AndroidRuntime(5668): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.akiand.wnb/com.akiand.wnb.main.Main}: java.lang.NullPointerException 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2185) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2210) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread.access$600(ActivityThread.java:142) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1208) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.os.Handler.dispatchMessage(Handler.java:99) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.os.Looper.loop(Looper.java:137) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread.main(ActivityThread.java:4931) 03-10 00:09:15.061: E/AndroidRuntime(5668): at java.lang.reflect.Method.invokeNative(Native Method) 03-10 00:09:15.061: E/AndroidRuntime(5668): at java.lang.reflect.Method.invoke(Method.java:511) 03-10 00:09:15.061: E/AndroidRuntime(5668): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 03-10 00:09:15.061: E/AndroidRuntime(5668): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:558) 03-10 00:09:15.061: E/AndroidRuntime(5668): at dalvik.system.NativeStart.main(Native Method) 03-10 00:09:15.061: E/AndroidRuntime(5668): Caused by: java.lang.NullPointerException 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:224) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:164) 03-10 00:09:15.061: E/AndroidRuntime(5668): at com.akiand.wnb.db.DBAdapter.open(DBAdapter.java:179) 03-10 00:09:15.061: E/AndroidRuntime(5668): at com.akiand.wnb.main.Main.onCreate(Main.java:76) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.Activity.performCreate(Activity.java:5008) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1090) 03-10 00:09:15.061: E/AndroidRuntime(5668): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2139) 03-10 00:09:15.061: E/AndroidRuntime(5668): ... 11 more </code></pre> <p>I couldn't find any reference for an error popping from SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:224)</p> <p>Your help is very much appreciated!</p>
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    1. COwhere is your setcontentview() in main.java
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    2. COmany a times it gives error if the setcontentview is not set
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    3. COmy setContentView(); was previously after dbA.open(); I tried now the same code, but instancing dbA and calling dbA.open(); after setContentView();, but I still get the same error...
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