During the DOAG SIG workshop I was asked how to create a treeview in Oracle APEX where the current selected tree node is highlighted.
After a quick thought about the problem, it turned out that there is a quite simple solution for it if you combine the treeview query with some HTML code.
- Create a regular tree region
- Create a form region which gets synchronized with your tree
- Change the tree query to contain the following CASE statement
SELECT EMPLOYEE_ID AS ID , MANAGER_ID AS PID , CASE WHEN EMPLOYEE_ID = 4_EMPLOYEE_ID THEN '<span style="color:white;background-color:blue;">'|| LAST_NAME|| '</span>' ELSE LAST_NAME END AS NAME , 'f?p=&APP_ID.:4:'||:SESSION||'::NO::P4_EMPLOYEE_ID:'||EMPLOYEE_ID AS LINK , NULL AS A1 , NULL AS A2 FROM #OWNER#.EMPLOYEES
What does it do?
When the tree is rendered the CASE compares the currently processed node (EMPLOYEE_ID) with the current active record (P4_EMPLOYEE_ID) which is displayed in the form.
If the IDs match, it wraps the LAST_NAME column with a SPAN which contains some styling information.
Quite simple, isn’t it?
View a working demo of the example.