A customer requirement had me a little stumped recently – to implement an Hierarchical List Applet based on the Action BC.
Looking in Bookshelf, there isn’t a lot said around the configuration of such applets. In fact, the guide basically tells you to look at an existing applet and work it out for yourself!
We at Ollerenshaw IT don’t want you to work it out for yourself, so we’ve worked it out for you. Here’s a guide to creating your own Hierarchical List Applet, based on the Action BC’s relationship with itself via ‘Parent Activity Id’:
- Create a new Project and lock
- In Tools, create a new List Applet via the wizard:
- Pick ‘Action’ as the underlying BC
- Pick ‘Applet List (Base/EditList)’ as the underlying template for Base and Edit List
- Choose a small number of fields to display
- Create Applet Method Menu Items:
- Indent
- Outdent
- MoveUp
- MoveDown
- Add the following User Properties to the Applet:
- CanInvokeMethod: Outdent = TRUE
- CanInvokeMethod: Collapse = TRUE
- CanInvokeMethod: Expand = TRUE
- CanInvokeMethod: Indent = TRUE
- Modify the ‘HTML Hierarchy Bitmap’ property of the Applet ‘List’ control to: ‘HTML Hierarchy Icons’
- Check out the ‘Action’ BC
- Modify the ‘Hierarchy Parent Field’ property of the BC to: ‘Parent Activity Id’
- Locally lock the ‘Activity List View’ for testing
- Replace the ‘Activity List Applet with Navigation’ applet with your new Applet
- Compile all objects and test
The icons and expand / collapse elements will display themselves on the first list column exposed on the applet. This doesn’t work if said column is a CHECK type, so I’d recommend exposing a unique field such as ‘Id’ and using this as the first column in the applet. Note also that you may want to use the ‘Disable Buscomp Hierarchy’ Applet User Property to disable this functionality where it’s not needed.
Finally, from all of us here Have a Merry Christmas and a Very Happy New Year!









