title: Show custom fileds based on other custom field value on CREATE ISSUE screen
body: <p>I'm implementing a help desk in JIRA where I have two drop downs - both '<strong>single value select</strong>' for <strong>Category</strong> and <strong>Sub-category</strong>.</p>
  
  <p>For example,
  I have following <strong>Categories</strong>:</p>
  
  <ul>
  <li>Content Development </li>
  <li>Events </li>
  <li>Design</li>
  </ul>
  
  <p>And each category has a list of <strong>sub-categories</strong> within them. For example, <strong>Design</strong> will have following list of options</p>
  
  <ul>
  <li>Event Collateral </li>
  <li>Branding</li>
  <li>Business Cards</li>
  </ul>
  
  <p>By default, ONLY <strong>Category</strong> dropdown should be displayed on the <strong>CREATE ISSUE</strong> screen.
  When user selects one of the <strong>categories</strong>, corresponding <strong>sub-category</strong> drop-down should be displayed on the CREATE ISSUE screen <strong>AND</strong> that sub-category dropdown should be MANDATORY field.</p>
  
  <p>I looked up for possible solution at the following links:</p>
  
  <ul>
  <li><a href="https://confluence.atlassian.com/display/JIRA052/Displaying+a+Field+Based+on+Another+Field+Selection" rel="nofollow noreferrer">https://confluence.atlassian.com/display/JIRA052/Displaying+a+Field+Based+on+Another+Field+Selection</a></li>
  <li><a href="https://confluence.atlassian.com/display/JIRA/Displaying+a+Field+Based+on+Another+Field+Selection" rel="nofollow noreferrer">https://confluence.atlassian.com/display/JIRA/Displaying+a+Field+Based+on+Another+Field+Selection</a></li>
  <li><a href="https://answers.atlassian.com/questions/217176/show-hide-custom-field-depend-on-another-custom-field-value" rel="nofollow noreferrer">https://answers.atlassian.com/questions/217176/show-hide-custom-field-depend-on-another-custom-field-value</a></li>
  </ul>
  
  <p>The first two links basically suggests the same solution - that is to put a JAVASCRIPT in the description field of the custom field and the same is suggested on many other blogs on this issue. They all give this very same example. </p>
  
  <p>However this is not working for me. When I put any JAVASCRIPT in the description of the custom-field, it runs immediately upon saving - on the <strong>Field Configuration</strong> screen. For example, I just put a following JAVASCRIPT in the description and I got the alert right away (on the <strong>Field Configuration</strong> screen).</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
  alert('hi');
   &lt;/script&gt;
  </code></pre>
  
  <p>However, I do not get any alert on the CREATE ISSUE screen. So, not sure if I am missing anything here. Please advise if I'm looking in the right direction.</p>
  
  <p>The 3rd link, suggests to create a plugin from the JIRA machine. However, I do not have access to that machine, I just have admin access to JIRA.</p>
  
  <p>Is there any feasible way to achieve it via default JIRA configurations/external plugins which are ready-to-use?</p>
  
  <p>My JIRA version is: 6.1.4</p>