text: 
  function add_listeners(ref_elem, update_elem, update_btn){
      function update(){
          update_elem.value = ref_elem.value;
          update_btn.removeAttribute('disabled');
      }
      ref_elem.addEventListener('mousedown', function(){
          this.addEventListener('mousemove', update);
      });
      ref_elem.addEventListener('mouseup', function(){
          this.removeEventListener('mousemove', update)
          update();
      });
  }
  
  var size_output_elems = document.getElementsByName('size_output');
  for(var i=0, len=size_output_elems.length;i<len;i++){
      var size_output_elem = size_output_elems[i];
      var size_id = size_output_elem.getAttribute('for');
      var size_elem = document.getElementById(size_id);
      var btn_id = size_output_elem.getAttribute('btn_id');
      var update_btn = document.getElementById(btn_id);
      add_listeners(size_elem, size_output_elem, update_btn);
  }
  
  document.getElementById('create_form').addEventListener('submit',function(){
      document.getElementById('create_submit').hidden = true;
      document.getElementById('size').setAttribute('readonly','true');
      document.getElementById('name').setAttribute('readonly', 'true');
      document.getElementById('loader').hidden = false;
  });
  
  document.getElementById('create_link').addEventListener('click', function(event){
      document.getElementById('create_row').hidden = false;
      event.preventDefault();
  }, false);