set wallpapers in CLI with new xfdesktop?

[houghi]

On Tue, Oct 15, 2013 at 12:38:24PM -0500, Paul Johnson wrote:
> I noticed the new xfdesktop 4.11 introduces the ability to put different
> wallpapers on different workspaces.  Great, that inability has been the reason
> I was running WindowMaker, Enlightenment, or Compiz.
> 
> So I built xfdesktop 4.11, leaving in place the other XFCE4.10 packages from
> Debian Jessie. It seems to work fine, I can open the xfdesktop gui configurator
> and set the background directory and choose one. The setup is not recursive
> into the subdirectories, that's not handy.  But, it does work.
> 
> I've got too many backgrounds in too many subdirectories for this pointy-clicky
> system. I have a Perl program that can randomly choose images and assign to
> workspaces.  I've used that in several window managers over the years.
> 
> I don't know how to talk to XFCE from the command line, though. Can you help?

The easy way. Not transferable to all systems or all users.
1) Run xfdesktop-settings and set it to one image (does not matter which
one) and zoomed or whatever you desire.
2) Run `xfconf-query -clv xfce4-desktop` to see what desktop(s) you use
and what the values are.

You can then change the image with e.g.
xfconf-query -c xfce4-desktop \
-p  /backdrop/screen0/monitor0/image-path \
-s /dir/to/image/somewhere.jpg


As an extra you can test and set all parameters.
e.g. `xfconf-query -c xfce4-desktop -p \
/backdrop/screen2/monitor0/image-show -n -s true` will turn the showing of
images on and changing it to false at the end will turn it off.

You can see what number the style has by changing it in xfdesktop-settings
and then running `xfconf-query -clv xfce4-desktop` to see what it becomes.

See http://docs.xfce.org/xfce/xfconf/xfconf-query for some more info.

I use 4 monitors with each a different wallpaper and change the wallpaper
on each of them every 60 seconds. The bash script I use for this is
http://houghi.org/script/background
The reason I use a script is because I am unable to properly do it with
the tools that are available for what I want.

houghi
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