If you run the Treeview demo that comes with Delphi for PHP, you see a couple of items in the treeview, and if you press the button "add node", a new node is added at the bottom of the treeview. If you click it again, same thing happens.
The content of the treeview persists when the page is reloaded, and that's what should be the normal behavior... and that's also what I want in my app.
If you add session_start() at the top of the php file, it stops working this way.
Each time you press "add node", the tree is emptied and only the currently added node is shown.
I have to use sessions in my app, but they mess up my treeview
What's the cause of this behavior?
How can I solve my problem?