user3686177 user3686177 - 2 months ago 8
Android Question

Deleting a single SQLite row

I am trying to delete a single row using

onLongClick
of list item but sometime it deletes the row and sometimes doesn't. Maybe I am passing the wrong id to it I don't getting what actually problem is.

I have tried some code and I am trying from last 2 days but unable to resolve this.

Below is my code.

@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, final int position, final long id) {
AlertDialog.Builder alert = new AlertDialog.Builder(FavouriteListActivity.this);
alert.setMessage("Do you want to unfavorite selected item ?");
alert.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Log.i("===========", "Position === " + position);
Log.i("===========", "long id === " + id);
deleteMethod(id);
showFavouriteList();
dialog.cancel();
}
});
alert.setNegativeButton("No", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alert.show();
return true;
}


And deleteMethod

private void deleteMethod(long Id) {
try {
long shId = Id + 1;
SQLiteDatabase db = OpenHelper.getDataHelper(getApplicationContext());
String query = "DELETE FROM " + LocalDatabase.FAVORITE_LIST.TABLE_FAVOURITE_LIST + " WHERE " + LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_ID + " = " + shId;
Log.i("QUERY", "" + query);
db.execSQL(query);
db.close();
} catch (Exception e) {
e.printStackTrace();
}
}


I am not getting any error, though, but it is not deleting item from database or from listview

Answer

First make a id variable in your model class and generate getter and setter for that:

public static final String PRIMARY_ID="_id";

Now set the primeary_id to model from the cursor:

if (cursor.moveToFirst()) {
            do {
                model = new FavouriteListVo(lngID, strName);
                  model.setStrName(cursor.getString(cursor.getColumnIndex(LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_NAME)));
model.setPrimId(cursor.getString(cursor.getColumnIndex(LocalDatabase.FAVORITE_LIST.PRIMARY_ID)));
                arrayListFav.add(model);
            } while (cursor.moveToNext());
        }

Now for deleting that row use this primary key:

 public void onClick(DialogInterface dialog, int which) {
            String id=model.getPrimId();
            deleteMethod(id);
            showFavouriteList();
            dialog.cancel();
        }

The delete function is exactlu same as yours, as I mentioned in comment that the problem is with id not your delete function:

private void deleteMethod(long Id) {
    try {
        long shId = Id + 1;
        SQLiteDatabase db = OpenHelper.getDataHelper(getApplicationContext());
        String query = "DELETE FROM " + LocalDatabase.FAVORITE_LIST.TABLE_FAVOURITE_LIST + " WHERE " + LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_ID + " = " + shId;
        Log.i("QUERY", "" + query);
        db.execSQL(query);
        db.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}
Comments