錯誤在檢索數據庫中的ListView

我的主類錯誤在檢索數據庫中的ListView

public class Tips2Main extends Activity{ 

DBOpener dbopener; 

/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    dbopener = new DBOpener(this);  
} 


@Override 
protected void onResume() { 
super.onResume(); 

// Configure the listview 
ArrayList<String> tips = new ArrayList<String>(); 
ListView lstTips = (ListView)this.findViewById(R.id.lst_tips); 
lstTips.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, tips)); 
dbopener.createDatabase(); 

    Cursor Tips = dbopener.getTips(); 
    while (Tips.moveToNext()) { 
     tips.add(Tips.getString(0)); // Get the current subj 
    } 
    Tips.close(); 
    lstTips.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, tips)); 


    // Update the listview 
    ArrayAdapter<String> ad = (ArrayAdapter<String>)lstTips.getAdapter(); 
    ad.notifyDataSetChanged(); 

    } 

    //Close the DB when app pauses 
    @Override 
    protected void onPause() { 
    super.onPause(); 
    dbopener.close(); 
    } 

    }

我的數據庫：

public class DBOpener extends Activity{ 
private static String DB_PATH = 
     "/data/data/sg.edu.iit.mns/databases/"; //path of our database 
    private static String DB_NAME ="Tips"; // Database name 
    private final Context myContext; 
    private SQLiteDatabase db; 

    public DBOpener(Context context) { 
     //super(context, DB_NAME, null, 1); 
     myContext = context; 
    } 

    public void createDatabase() { 
     boolean dbExists = checkDatabase(); 
     if (!dbExists) { 
      try 
      { 
       copyDatabase(); 
      } 

      catch (IOException e) 
      { 
       Toast.makeText(myContext, "Error", Toast.LENGTH_LONG).show(); 
      } 
     } 
     String path = DB_PATH + DB_NAME; 
     db = SQLiteDatabase.openDatabase(path, null, SQLiteDatabase.OPEN_READWRITE); 
    } 

    private boolean checkDatabase() { 
     File database = new File(DB_PATH + DB_NAME); 
     return database.exists(); 
    } 

    private void copyDatabase() throws IOException { 
     InputStream istream = myContext.getAssets().open(DB_NAME); 
     OutputStream ostream = new FileOutputStream(DB_PATH + DB_NAME); 

     // Transfer bytes from istream to ostream 
     byte[] buffer = new byte[1024]; 
     int length; 
     while ((length = istream.read(buffer)) > 0) { 
      ostream.write(buffer, 0, length); 
     } 
     // Close streams 
     istream.close(); 
     ostream.flush(); 
     ostream.close(); 
    } 

    public synchronized void close() 
    { 
     if(db !=null) 
      db.close(); 
    } 

    // Retrieve tips 
    public Cursor getTips() { 
     if (db == null) 
      return null; 
     return db.query("tips", new String[] {"Tips"}, 
      null, null, null, null, null); 
    }

錯誤日誌：

 06-06 04:21:34.214: I/Database(719): sqlite returned: error code = 14, msg = cannot open file at source line 25467 
    06-06 04:21:34.224: E/Database(719): sqlite3_open_v2("/data/data/sg.edu.iit.mns/databases/Tips", &handle, 2, NULL) failed 
    06-06 04:21:34.224: D/AndroidRuntime(719): Shutting down VM 
    06-06 04:21:34.224: W/dalvikvm(719): threadid=1: thread exiting with uncaught exception (group=0x4001d800) 
    06-06 04:21:34.264: E/AndroidRuntime(719): FATAL EXCEPTION: main 
    06-06 04:21:34.264: E/AndroidRuntime(719): java.lang.RuntimeException: Unable to resume activity {sg.edu.iit.mns/sg.edu.iit.mns.Tips2Main}: android.database.sqlite.SQLiteException: unable to open database file 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3128) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3143) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2684) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.access$2300(ActivityThread.java:125) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.os.Handler.dispatchMessage(Handler.java:99) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.os.Looper.loop(Looper.java:123) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.main(ActivityThread.java:4627) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at java.lang.reflect.Method.invokeNative(Native Method) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at java.lang.reflect.Method.invoke(Method.java:521) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at dalvik.system.NativeStart.main(Native Method) 
    06-06 04:21:34.264: E/AndroidRuntime(719): Caused by: android.database.sqlite.SQLiteException: unable to open database file 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.database.sqlite.SQLiteDatabase.dbopen(Native Method) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1812) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:817) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at sg.edu.iit.mns.DBOpener.createDatabase(DBOpener.java:41) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at sg.edu.iit.mns.Tips2Main.onResume(Tips2Main.java:33) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1149) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.Activity.performResume(Activity.java:3823) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3118) 
    06-06 04:21:34.264: E/AndroidRuntime(719):  ... 12 more

當我嘗試POPU從數據庫延遲我的listview，它強制關閉應用程序。我不知道如何檢查錯誤並使其運行。這裏沒什麼幫助，謝謝。數據庫已位於資產文件夾內。

來源

2012-06-06 Riyas2329

你打開了你的數據庫嗎？ – drulabs

是已經打開。 – Riyas2329

這是你的錯誤「android.database.sqlite.SQLiteException：無法打開數據庫文件」。我會在你的DBOpener類中擴展SQLiteOpenHelper。看到這個示例應用程序，特別是類此網址進行快速模板：http://developer.android.com/resources/samples/SearchableDictionary/src/com/example/android/searchabledict/DictionaryDatabase.html

來源

2012-06-06 05:04:14

試試這個鏈接，它提供了有關SQLite和樣品太詳細的描述..

AndroidSQLite

SQLite Samples

它可能會幫助你......

來源

2012-06-06 05:15:48 deepa

1.）爲什麼要從Activity類擴展你的數據庫類？
變化

public class DBOpener extends Activity{

到

public class DBOpener{

2）在你的數據庫類添加這個方法：

public DBOpener openDB() throws SQLException { 
    db = dataHelper.getWritableDatabase(); 
    return this; 
}

調用此方法從copyDatabase()

private void copyDatabase() throws IOException { 
    InputStream istream = myContext.getAssets().open(DB_NAME);

希望它有幫助！

來源

2012-06-06 06:22:29 GAMA

錯誤在檢索數據庫中的ListView

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