ADF 12c Bug – Unable to Display Gantt Chart With Subtasks Correctly in ADF 12c

Description of the Problem

I faced a weird bug in ADF 12c recently that caused the Gantt chart not to be displayed correctly, and by correctly I mean that the Gantt chart is displaying but without some properties that changes how it looks, for instance the chart doesn’t display Task Types (“Normal”, “Summary” or “Milestone”) correctly, it also doesn’t display % complete nor Critical, even though you specified everything the right way.


JDeveloper: OS: Win 7 JDK: 1.7_45

How to generate the same problem

  1. In order to generate this problem, let’s start with a small Table structure like the following:
    Notice that there is a recursive relationship using the

    You can use This script to generate the Table with some dummy data.

  2. Next we need to create a small model with this table, so just use the Business Components from Table to generate The Entity Object, association, View Object, View Link and the Application Module.If you’ve done everything right, you should end up with something similar to the below screenshot.

  3. Add another attribute inside the Tasks View Object and call it CriticalBool with type Boolean with the following expression

    Critical == 'true'

  4. Now it’s time for the Drag and Drop, Create a JSF page and Drag and Drop Task View 1 as Project Gantt chart.

    4.1. Define the Attribute like the below screenshot

    4.2. Define the Subtasks like the below screenshot

    4.3. Define the Appearance like the below screenshot

    4.4. Run your Page and examine the result

    4.5. Strangely if you follow the same steps with JDeveloper you will find a different end result


If you didn’t use Subtasks view you will not face this problem, but you will end up with a Flat Design, but if you can live with that, this problem should not bother you in the first place.


This might need to be fixed in the next releases, but till then you can keep your eyes on it at the ADF EMG Jira