How to collapse blocks of code in Eclipse?

Some days ago my Eclipse was working fine and a +/- appeared in every block that could be collapsed (functions, classes, etc.)... but now it does appear, and I don't know how to activate that feature again.

It's Eclipse Helios, running on a Gentoo Linux box.

Solution 1:

Preferences -> C++ -> Editor -> Folding ?

Make a right click in the editor window and go to preferences there, then only the editor-relevant section of the preferences dialog will appear. This works for JDT, CDT etc...

Solution 2:

You can do ( Ctrl + Numpad_Divide ) to enable folding.
Also if you Right Click on the area where the + or - was supposed to be, you can see there is a folding option.

Solution 3:

Try this option: Preferences > Java > Editor > Folding > Enable folding