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

If you want to know if this contact has WhatsApp:

String[] projection = new String[] { RawContacts._ID };
String selection = ContactsContract.Data.CONTACT_ID + " = ? AND account_type IN (?)";
String[] selectionArgs = new String[] { "THE_CONTACT_DEVICE_ID", "com.whatsapp" };
Cursor cursor = activity.getContentResolver().query(RawContacts.CONTENT_URI, projection, selection, selectionArgs, null);
boolean hasWhatsApp = cursor.moveToNext();
if (hasWhatsApp){
    String rowContactId = cursor.getString(0);
}

And to find to which number of this contact has WhatsApp

projection = new String[] { ContactsContract.Data.DATA3 };
selection = ContactsContract.Data.MIMETYPE + " = ? AND " + ContactsContract.Data.RAW_CONTACT_ID + " = ? ";
selectionArgs = new String[] { "vnd.android.cursor.item/vnd.com.whatsapp.profile", rawContactId };
cursor = CallAppApplication.get().getContentResolver().query(ContactsContract.Data.CONTENT_URI, projection, selection, selectionArgs, "1 LIMIT 1");
String phoneNumber = null;
if (cursor.moveToNext()) {
    phoneNumber = cursor.getString(0);
}