Frequent queries on android contacts returns null

Question

I'm using the following code segment to get phone numbers of a contact by contact ID

private static ArrayList<PhoneName> getPhonesFromID(Context context,
            String contactID, String column) {
        // Run query
        Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
        String[] projection = new String[] {
                ContactsContract.CommonDataKinds.Phone._ID,
                ContactsContract.CommonDataKinds.Phone.CONTACT_ID,
                ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME,
                ContactsContract.CommonDataKinds.Phone.NUMBER,
                ContactsContract.CommonDataKinds.Phone.STARRED,
                ContactsContract.CommonDataKinds.Phone.TYPE };
        String selection = column + " = '" + contactID + "'";
        String[] selectionArgs = null;
        String sortOrder = ContactsContract.CommonDataKinds.Phone.NUMBER
                + " COLLATE LOCALIZED ASC";

        Cursor cursor = context.getContentResolver().query(uri, projection,
                selection, selectionArgs, sortOrder);

        if (cursor == null)
            return null;

        int numberIndex = cursor
                .getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER);
        int nameIndex = cursor
                .getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME);
        int typeIndex = cursor
                .getColumnIndex(ContactsContract.CommonDataKinds.Phone.TYPE);
        int favIndex = cursor
                .getColumnIndex(ContactsContract.CommonDataKinds.Phone.STARRED);

        ArrayList<PhoneName> phones = new ArrayList<PhoneName>();
        while (cursor.moveToNext()) {
            PhoneName pn = new PhoneName();
            pn.name = cursor.getString(nameIndex);
            pn.number = cursor.getString(numberIndex);
            pn.starred = cursor.getString(favIndex);
            pn.state = DataHelper.getInstance(context)
                    .getSubscriptionStateByNumber(pn.number);
            Log.d("Number", pn.number);
            int type = cursor.getInt(typeIndex);
            if (type == ContactsContract.CommonDataKinds.Phone.TYPE_HOME) {
                pn.type = "Home";
            } else if (type == ContactsContract.CommonDataKinds.Phone.TYPE_MOBILE) {
                pn.type = "Mobile";
            } else if (type == ContactsContract.CommonDataKinds.Phone.TYPE_WORK) {
                pn.type = "work";
            } else {
                pn.type = "other";
            }
            phones.add(pn);
        }

        cursor.close();
        return phones;
    }

Here's PhoneName is my self-defined class to store contact information of that specific contact. This function is called like:

getPhonesFromID(context, _id,
                    ContactsContract.CommonDataKinds.Phone.CONTACT_ID);

I'm getting the contact information correctly but here's the problem, sometimes this function returns null when I make frequent queries. When this problem occurs, default people application of my android don't show any contact too. All contacts are like vanished. Then if I close my application and restart then it shows all contacts like before. Then again when I go to the contact details of a contact from my application it works fine several times and then all contacts are gone again. This is a weird problem and I don't know actually what is happening here. I double checked my queries and couldn't figure out what's wrong in here.

Answer 1

Finally, this problem got solved.

Like I said, my application is like Phonebook and I had to show a favourite icon for each contact in the list which is my favourite contact. In my case, I had a function like isFavourite() to determine if a contact is in my favourite list or not and this is called in every single time when a contact row is loading.

Each time I open a cursor to get the query result and it was found that the cursor was not closed anywhere. So basically, closing the cursor properly solved the problem! Cheers!