title: Adding a hierarchical Gantt-Chart in Oracle Apex
body: <p>I'm trying to add a Gantt-Chart (Oracle JET) with hierarchical data to my Oracle Apex (19.1) Application just like the example in the Cookbook (<a href="https://www.oracle.com/webfolder/technetwork/jet/jetCookbook.html?component=gantt&amp;demo=hierarchicalTasks" rel="nofollow noreferrer">Hierarchical Tasks</a>) by using the built-in implementation in Apex.</p>
  <p>In this example, a JSON-file containing the tasks, which can have children-elements called <code>subTasks</code> gets parsed and rendered. However, I'm getting my data from a local database.</p>
  <p>Is this feature possible in the Apex-version of oracleJET? Or do I have to implement the Gantt-chart from OracleJET as if it was a 3rd-party-solution?</p>
  <p>Because I am able to create a normal Gantt-chart without a hierarchy, however, I haven't quite figured out, how to implement one with a hierarchy.</p>
  <p>According to the documentation of <code>ArrayTreeDataProvider</code>, the default-keyword for child-elements to be located in is 'children'. But it doesn't matter how I format my data (selecting it from the database with <code>json_object()</code> and <code>json_arrayagg()</code> ), it only renders the 'parent' elements.</p>
  <p>Does anyone have already implemented this/a similar functionality into an Apex Application and can help me out?</p>
  <p>Thanks a lot in advance!</p>