How to make Custom Walker for wp_nav_menu() for materialize framework

I’ve made something like this:

    <div class="navbar-fixed"> 
   <nav>
        <div class="nav-wrapper">
            <a href="#!" class="brand-logo"><?php _e('Logo', 'newborn'); ?></a>
            <a href="#" data-activates="mobile-demo" class="button-collapse"><i class="mdi-navigation-menu"></i></a>
            <ul class="right hide-on-med-and-down">
                <?php wp_nav_menu( array( 'theme_location' => 'primary-menu' ) ); ?>
            </ul>
        <ul class="side-nav" id="mobile-demo">
          <?php wp_nav_menu( array( 'theme_location' => 'primary-menu' ) ); ?>
        </ul>

        </div>
    </nav>
        </div>

Plus this css:

.menu ul{display: none;}
.menu li:hover ul{display: block;}

And now it works….BUT!

Still issue No.4 which i said on the top exist (special when i add home link into navbar) and the dropdown menu is not so pretty! it’s so simple without any change with their parent links.