Render Windows Without Explicit Attach

[mbalkanloo]

Currently, windows are not rendered until a client "attaches". This means that commands such as xdotool have no available windows to operate on until an explicit call to xpra attach is made in a terminal session with X11 forwarding. I have tried many variations of xdotool commands to try to force rendering but to no avail. To allow rendering without an explicit attach would significantly enhance automation capabilities and I would be enormously grateful for this feature.

Thank you for considering this request and thank you for developing and supporting Xpra.

[totaam]

The original discussion on the mailing list is here: Render Without Attach

OTOH, we just need a new control channel command to trigger WindowModel.map().

[mbalkanloo]

Thank you for reviewing this request.

I have found that I am able to achieve the desired result by running Xvfb directly.

I simply run the GUI application in an Xvfb session, use xdotool commands to interact with the interface, and subsequently run xpra start-desktop if I need to attach and interact with the GUI manually.

Please feel free to close the request if you like.

[totaam]

That was easy, with the commit above you can do (I added sync-xvfb to the command be able to see the state of the virtual screen using scrot or other screen capture tools):

xpra start --start=xterm --sync-xvfb=20 :100

Then:

WID=1
xpra control :100 map $WID
# the window shows up on the vfb, then:
xpra control :100 unmap $WID

The first window to show up will be 1, you can identify your windows with xpra info.