How to show searchResultsTableView when searchbar is activated?

I am implementing a UISearchDisplayController and I would like to populate the searchResultsTableView with the content of the tableView (unfiltered) right on load - before text is being entered.

This works when I start entering values in the searchBar.

- (void)searchDisplayControllerWillBeginSearch:(UISearchDisplayController *)controller {
    self.isSearching = YES;

    //tell the searchDisplayTableView to show here!

    [controller.searchBar setShowsCancelButton:YES animated:YES];
}

- (void)searchDisplayControllerDidEndSearch:(UISearchDisplayController *)controller {
    self.isSearching = NO;
    [controller.searchBar setShowsCancelButton:NO animated:YES];
}

Would anybody have any pointers into the right direction?

Please don't reply with "don't do that" or "Apple did not design the control that way." or ...