Question

I am looking for a fast & efficient way to query the Android contacts given an email address (basically, given an email address I want to find the matching contact if it exists). Currently I have a double While loop and it’s probably the most inefficient way to accomplish this.

I imagine that I have to do a custom SQLite join query, but I am unfamiliar with how to do this. Any help or pointers from other users would be appreciated!

Answer 1

After a little bit more research, there is no contract that handles this type of request and you can’t do any custom SQL query on any DB that you don’t own. I have come up with the best solution that I could. Please comment on this and let me know if there is a way to make this perform any better/faster/efficient.

String incomingEmail = [EMAIL_WE_ARE_SEARCHING_FOR]...
long contactID = -1;
//Filter by email address first.
final String[] emailProjection = new String[]{ContactsContract.CommonDataKinds.Email.CONTACT_ID, 
    ContactsContract.CommonDataKinds.Email.DATA};
final String emailSelection = ContactsContract.CommonDataKinds.Email.DATA + "=?";
final String[] emailSelectionArgs = new String[]{incomingEmail};
final String emailSortOrder = null;
Cursor emailCursor = context.getContentResolver().query(
        ContactsContract.CommonDataKinds.Email.CONTENT_URI, 
        emailProjection,
        emailSelection, 
        emailSelectionArgs, 
        emailSortOrder);
if(emailCursor.moveToFirst()){
    contactID = emailCursor.getLong(emailCursor.getColumnIndex(ContactsContract.CommonDataKinds.Email.CONTACT_ID)); 
    //Query the specific contact if found.
    final String[] projection = new String[]{ContactsContract.Contacts._ID, 
        ContactsContract.Contacts.DISPLAY_NAME, 
        ContactsContract.Contacts.PHOTO_ID, 
        ContactsContract.Contacts.LOOKUP_KEY};
    final String selection = ContactsContract.Contacts._ID + "=?";
    final String[] selectionArgs = new String[]{String.valueOf(contactID)};
    final String sortOrder = null;
    Cursor contactCursor = context.getContentResolver().query(
            ContactsContract.Contacts.CONTENT_URI,
            projection, 
            selection, 
            selectionArgs, 
            sortOrder);             
    if(contactCursor.moveToFirst()){
        contactName = contactCursor.getString(contactCursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
        String photoIDTmp = contactCursor.getString(contactCursor.getColumnIndex(ContactsContract.Contacts.PHOTO_ID)); 
        if(photoIDTmp != null){
            photoID = Long.parseLong(photoIDTmp);
        }
        lookupKey = contactCursor.getString(contactCursor.getColumnIndex(ContactsContract.Contacts.LOOKUP_KEY));
    }
    contactCursor.close();      
}else{
    emailCursor.close();
    return null;                
}
emailCursor.close();
//Return Contact ID, Contact Name, Contact Photo, Etc.

Thanks!