How to Check if a contact on android phone book has whatsapp enabled?

Question

For a given number from my address book, I need to look-up if the number has whatsapp enabled. (The idea is to choose SMS/WhatsApp for initiating a text intent)

Lets say

Answer 1

public int hasWhatsApp(String contactID) {
        int whatsAppExists = 0;
        boolean hasWhatsApp;

        String[] projection = new String[]{ContactsContract.RawContacts._ID};
        String selection = ContactsContract.Data.CONTACT_ID + " = ? AND account_type IN (?)";
        String[] selectionArgs = new String[]{contactID, "com.whatsapp"};
        Cursor cursor = getActivity().getContentResolver().query(ContactsContract.RawContacts.CONTENT_URI, projection, selection, selectionArgs, null);
        if (cursor != null) {
            hasWhatsApp = cursor.moveToNext();
            if (hasWhatsApp) {
                whatsAppExists = 1;
            }
            cursor.close();
        }
        return whatsAppExists;
    }