properly show SVProgressHUD when resigning keyboard

Resign keyboard SVProgressHUD

// resign keyboard

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0.3 * NSEC_PER_SEC), dispatch_get_current_queue(), ^{
        [SVProgressHUD showWithStatus:@"Searching..." maskType:SVProgressHUDMaskTypeBlack];

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            //do search
            dispatch_async(dispatch_get_main_queue(), ^{
                //search finished - do smth with search results and hide hud
                [SVProgressHUD dismiss];
            });
        });
    });