How to allow database operations to take place in a fragment?

Question

I am new to database in Android but now I know the way to apply CRUD (Create, Read, Update, Delete) operations on an activity but in case of fragments, getWritableDatabase() is not working. I would like to know the best way to apply CRUD operations in fragments. In activities, I made a class to handle database operations and then made its' object in the activity and was able to work on it thereafter.

Answer 1

Try

DbHelper helper = DbHelper.getInstance(getContext());
SQLiteDatabase db = helper.getWritableDatabase();` 

instead

Answer 2

Here I tried to illustrate calling db from fragment class :

SQLiteDatabase db = context.getWritableDatabase(); // 'this' for activity

Initialize db object inside onAttach() or onActivityCreated() any other method : [onAttach() is preferable]

public Cursor getAllData() {
  Cursor result = db.rawQuery("SELECT * FROM "+ TABLE_NAME, null);
  return result; 
}

Tips: You should use these type of db calls into the background threads, not to invoke or block the UI thread which will result a better performance.