Lubuntu 18.10 File Manager: How to view directory tree structure?

Solution 1:

Another Qt based (like Lubuntu 18.10 is) alternative is dolphin from KDE

By default it didn't show as you wanted, but select

Control -> Panels -> Folders

to have folders show in a tree like fashion on the left panel.

The following picture was from my 19.04 box, but it responded identically on the 18.10 QA-test box (x86/i686) besides me I just tested it on.

there may be other alternatives, and which is best for you is your choice. Sorry I couldn't get it to view on my play with pcmanfm-qt

Install with sudo apt install dolphin

Solution 2:

A file manager that may do what you want and won't pull in too many dependencies is Thunar. Install it by running sudo apt install thunar. After it's installed, you'll find it under Menu > System:

The image shows how to switch to Tree View.

Note that Thunar is a gtk application and nicely obeys the Blackbird theme of light text on a dark background as described here.

As other answers indicate, there are other options available. If your interested to know the list of dependencies pulled in by each, you could do a simulation of an install by running sudo apt install -s thunar or sudo apt install -s dolphin or sudo apt install -s caja, etc. The simulation requires the inclusion of -s but does not need sudo and so is quite harmless.

Solution 3:

Another alternative is Caja from MATE DE (GNOME 2 fork).

By default its Side Pane shows Places, but you can switch it to Tree view:

You can combine Places view in side pane with List View of main panel to show directory tree:

Also as free bonus you can enable Extra Pane (with F3) to combine views - for example List View in the left and Icon View in the right:

You can install Caja with

sudo apt install caja