sqlite delete row by onItemLongClick gridview sqlite

Question

i have a gridview that get data from an sqlite database and i want to delete a row by onItemLongClick but i get a error i cannot solve it

@Override
public boolean onItemLongClick(AdapterView<?> parent, View view,
                               int position, long id)
{
    dataBase.delete(mDBHelper.TABLE_LIENS, mDBHelper.toString()
                                           + "="
                                           + mLienList.get(position), null);

    mLienList.remove(position);
    adapter.notifyDataSetChanged();
    Toast.makeText(Main2ActivityAdmin.this, "Lien supprimer", Toast.LENGTH_LONG).show();

    return true;
}

stack trace is:

E/AndroidRuntime: FATAL EXCEPTION: main Process: PID: 21230 java.lang.NullPointerException: Attempt to invoke virtual method 'int android.database.sqlite.SQLiteDatabase.delete(java.lang.Stri‌ng, java.lang.String, java.lang.String[])' on a null object reference

did you see the last param of `onItemLongClick`? this is the row ID that you can use to delete the particular row in your db — pskink, Sep 04 '16 at 13:47

score 1 · Answer 1 · edited May 23 '17 at 10:27

1

According to your stack trace you don't initial your SQLiteDatabase, so when use it, exception has been occurred. see this answer. it gives you an idea to modify your code.

edited May 23 '17 at 10:27

Community

1
1

answered Sep 04 '16 at 14:14

Saeed Zhiany

2,051
9
30
41

score 0 · Answer 2 · answered Sep 04 '16 at 14:14

0

if error coming from sqlite, you have to make sure that your whereClause is correct value

db.delete(table, whereClause, whereArgs);

and make sure you have initialize your database variable, in my case

db = new DB(this);
db.open();

answered Sep 04 '16 at 14:14

Muklas

557
7
11

i already initialize my database – trabajo needit Sep 04 '16 at 22:32

sqlite delete row by onItemLongClick gridview sqlite

2 Answers2