If you want dual monitor functionality in Lubuntu, you have limited options. The following will show you how to enable and disable dual monitors "on the fly" using aRandR as help. These directions are a bit complicated, but trust me: they are not dangerous. This is a SAFE operation.
First, get aRandR from Synaptic or by opening the terminal and pasting:
sudo apt-get install arandr
You can find your new application under Menu -> Preferences
What you see is a virtual setup of your monitor arrangement. You will almost certainly have different names for your monitor, but here is what mine looks like.
Although you haven't really done anything at this point, save this configuration.
It will automatically create a new hidden folder called .screenlayout in your home directory. I would encourage you to not change the file location to help with later steps. I would also encourage you to use my file names as well. This one should be called "single"
Now add your second monitor. It should be hooked up to your computer at this point, of course. I added mine by scrolling through the only other monitors that allowed activation and selected it.
Position the monitors however you like. I prefer side-by-side, but you may also put one above the other. It doesn't matter which one is on the left (or the top). It's all up to you! Here's what I like:
Once you have your desired configuration, save it again. This time, name the file "dual".
The last step in this whole process is creating hotkeys to switch monitor on the fly. You may want to read
this post first to give you an idea of what we're doing here. In the terminal type in the following:
sudo leafpad ~/.config/openbox/lubuntu-rc.xml
Scroll down to a place where you begin to see a lot of words that say <keybind>. You don't need to know what's happening here. Simply find a place after a </keybind>, but before the next <keybind> and paste the following:
<keybind key="W-2">
<action name="Execute">
<command>sh ~/.screenlayout/dual.sh</command>
</action>
</keybind>
<keybind key="W-1">
<action name="Execute">
<command>sh ~/.screenlayout/single.sh</command>
</action>
</keybind>
Your code should look a little like this:
Save. Close. Logout.
If you did everything right, you should be able to press
Super-2 to activate dual monitor mode. To go back to one monitor, such as your laptop, press Super-1.
One final note about the lxde panel. When I switched into dual mode, my panel looked a little funny. If you experience this problem, open up your files you created with aRandR in the .screenlayout directory. Add the following lines to the bottom of the files:
lxpanelctl restart
Credit for much of this comes from this
official Lubuntu screencast. If the method above doesn't work for you, the screencast give some other methods for achieving a dual monitor setup. Good luck.
Again, in the terminal, type
