title: Don't allow sorting in a sortable list, only use connectWith to move them to a different sortable list
body: <p>I am using jQuery UI's <code>.sortable</code> feature. I have list a and list b. I want the user to be able to:</p>
  
  <ul>
  <li>Drag items from list a to list b but not from list b to list a</li>
  <li>Sort items in list b but <strong>not</strong> in list a</li>
  </ul>
  
  <p>My code meets only meets the first requirement. I can't stop items being sorted in list a.</p>
  
  <p>While the code in the answer <a href="https://stackoverflow.com/a/14442218/5798798">https://stackoverflow.com/a/14442218/5798798</a> automatically reverses any sorting done in a list, it doesn't prevent sorting within it all together (which is what I'm looking for).</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>$("#sortable").sortable({
    connectWith: "#sortable2"
  });
  
  $("#sortable2").sortable({});</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://code.jquery.com/jquery-1.12.4.js"&gt;&lt;/script&gt;
  &lt;script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"&gt;&lt;/script&gt;
  &lt;p&gt;List A&lt;/p&gt;
  &lt;div id="sortable"&gt;
    &lt;li&gt;Item 1&lt;/li&gt;
    &lt;li&gt;Item 2&lt;/li&gt;
    &lt;li&gt;Item 3&lt;/li&gt;
  &lt;/div&gt;
  &lt;p&gt;List B&lt;/p&gt;
  &lt;div id="sortable2"&gt;
    &lt;li&gt;Item 1&lt;/li&gt;
    &lt;li&gt;Item 2&lt;/li&gt;
    &lt;li&gt;Item 3&lt;/li&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>JsFiddle: <a href="http://jsfiddle.net/g5nxjk0e/1/" rel="nofollow noreferrer">http://jsfiddle.net/g5nxjk0e/1/</a></p>
  
  <p><em>Note that there could be multiple lists that list a can be dragged into</em></p>