Thunar, the default file manager for Xfce, and does not support split view. In a bug reported in 2013 this feature was requested, but Nick Schermer, one of the Thunar developers, said that Thunar would not have split view support because "Thunar is intended by design to be simple and easy to use«.
Since Thunar is open source software, Roman, an XFCE user, decided to take this matter into his own hands and implement the split or double panel in Thunar and has released a patch, so all those looking for this feature can use their work.
Maybe the XFCE developers will change their mind and implement this feature at some point (or maybe not), but until then, if you really need this feature, you can grab the patch from here. If you use Xubuntu 14.04 o 14,10, Andrew (from Webupd8) has uploaded Thunar with the split view patch to a PPA so it can be easily installed.
Before using this patch, it is important to note that currently, the split view that we are going to get is quite basic: It does not appear in the Thunar menu (you must use "F3" to activate the panel), and you cannot set Thunar to start in split view mode by default. Also, the patch may be buggy.
How to install split view in Thunar?
This PPA is for testing only! Andrew clarifies that he is not a programmer and any bugs related to the split view feature will remain until someone updates the patch.
To add the PPA we type:
sudo add-apt-repository ppa: webupd8team / experiments sudo apt-get update sudo apt-get install thunar thunar -q
And finally, restart Thunar:... "F3" is used to turn the additional panel on / off.
How to reverse the changes
If you want to revert the changes and go back to the Thunar version from the official Xubuntu repositories, we remove the PPA using ppa-purge:
sudo apt-get install ppa-purge sudo ppa-purge ppa: webupd8team / experiments
Article and pictures taken from Webupd8