How to view the records in database via Click Event in Android?

I am using a cursor to view my records in a database. But an error is displayed.

ERROR/AndroidRuntime(3880): java.lang.IllegalStateException: get field slot from row 1 col -1 failed Run Time Excweption Sir – mnom 2 mins ago edit

Here is my code:

     btn4.setOnClickListener(new View.OnClickListener(){开发者_StackOverflow中文版
      public void onClick(View v){  
          dh.open();
          Cursor c = dh.DisplayTitle();
          String text = "";
          c.moveToFirst();
          while (c.moveToNext()) {
              text = text+ "typ: " + c.getString(c.getColumnIndex(dh.DisplayTitle().toString()));

          }

And my Datahelper code:

public Cursor DisplayTitle()throws SQLException
{
     Cursor c1=db.rawQuery("SELECT * from titles",new String []{});
     if (c1 != null) {
         c1.moveToFirst();
     }

     return c1;
    }