javascript - Preventing multiple toggling at a same time -

how can prevent slidedown , slide of sub menu @ same time?my navigation has menu , 1 of menus has sub menu.when click on menu has sub menu , sub menu opens,closes 2 times , closes there 1 click.it happens in mobile devices.so take @ codes

html

<ul class="nav-menu align-right">   <li class="current"><a href="index.html#header">home</a></li>   <li><a href="index.html#about-us">about us</a></li>   <li>     <a href="#" class="extra">extra</a>     <ul>         <li><a href="blog-three.html">blog grid 3</a></li>         <li><a href="blog-four.html">blog grid 4</a></li>     </ul>   </li>   <li><a href="index.html#contact">contact</a></li></li>    </ul> 

and js

$(window).on('load resize', function(){     if($(window).width() < 1000){        $('.nav-menu li a').click(function(e) {           e.preventdefault();           $(this).next('ul').slidetoggle(200, 'easeinexpo');           $(this).parent().siblings().find('ul').slideup(200, 'easeinexpo');         });     }  }) 

you binding events everytime window resized trigger multipe times. if chamge should work jsfiddle

$(window).on('load', function(){     $('.nav-menu li a').click(function(e) {         if($(window).width() < 1000){             e.preventdefault();             $(this).next('ul').slidetoggle(200, 'easeinexpo');             $(this).parent().siblings().find('ul').slideup(200, 'easeinexpo');          }     });  })