How do I set "button 2" of mouse to "show desktop"

Question

My middle mouse button (the scroll wheel pressed down), after turning off the gnome-tweak middle click is paste, shows as button 2 in xev:

ButtonPress event, serial 37, synthetic NO, window 0x3400001,
    root 0x4ee, subw 0x0, time 8879244, (79,71), root:(1759,879),
    state 0x10, button 2, same_screen YES

ButtonRelease event, serial 37, synthetic NO, window 0x3400001,
    root 0x4ee, subw 0x0, time 8879452, (79,71), root:(1759,879),
    state 0x210, button 2, same_screen YES

It now functions in browsers to open links in a new tab. I want it to show the desktop.

I installed wmctrl and can show desktop by typing into terminal wmctrl -k on. But I cannot figure out how to associate button 2 with that command.

In Settings > Keyboard > Shortcuts > Custom, adding the command works, but it is not possible to associate it with the button click.

In dconf editor, I tried using xautomation and the command xte 'mouseclick 2', but that didn't work either (nor did button 2 or 'button 2' or button2.

Any idea what the correct binding is for button 2 in dconf editor or how to get the Settings menu to accept it?

Answer 1

If you didn't already, install xbindkeys:

sudo apt-get install xbindkeys

Then we'll need to find out whats you mouse-button called (usually Button2, but we'll want to be sure). write xev |grep button in terminal. A white window will appear. Do a middle click inside and read the output in terminal, eg:

 state 0x10, button 2, same_screen YES
state 0x210, button 2, same_screen YES

So for me its button 2.

Now write a default xbindkey-file with:

xbindkeys --defaults > $HOME/.xbindkeysrc 

Edit the file with scratch or: nano .xbindkeysrc

Look if there's allready an entry for your middle button, edit it or make a new one as following:

#show desktop
"wmctrl -k on"
   b:2

Save the file. (with nano it's Ctrl+O).

Run xbindkey in terminal. If it's working add xbindkey to your startup-applications.