How to get xid on Windows?

luislavena · October 1, 2011, 6:39am

Hi folks,

When I ran the following tiny snippet on my Windows 7,

require ‘gtk2’
win = Gtk::Window.new
win.signal_connect(‘expose-event’) do
p win.window.xid
end
win.show_all
Gtk.main

I got the error: undefined method `xid’ for #<Gdk::Window:02735E38
ptr=026D9170>

But on Ubuntu on VirtualBox for Windows 7, it works well.
(I got the number of xid.)

Could you show me how to get a xid on Windows?

Thanks,
ashbb

satoshi_a · October 1, 2011, 9:56pm

hi ash,

interesting - confirmed the same issue comparing Ubuntu and WinXP.

running this…

require ‘gtk2’
win = Gtk::Window.new
win.signal_connect(‘expose-event’) do
win.window.methods.sort.each{|m| p m}
end
win.show_all
Gtk.main

…shows that the #xid method exists in ubuntu, but not in windows.
strange…

j

satoshi_a · October 2, 2011, 2:20pm

Satoshi A. wrote in post #1024450:

How to get xid on Windows?

Hi folks,

When I ran the following tiny snippet on my Windows 7,

require ‘gtk2’
win = Gtk::Window.new
win.signal_connect(‘expose-event’) do
p win.window.xid
end
win.show_all
Gtk.main

I got the error: undefined method `xid’ for #<Gdk:02735E38
ptr=026D9170>

http://ruby-gnome2.sourceforge.jp/hiki.cgi?cmd=view&p=Gdk%3A%3ADrawable&key=xid#xid
:
Returns the X11 (X Window) XID of this Gdk::Drawable, as a number. X
only

Notice the “X only”. Windows does not use X.

Simon

satoshi_a · October 3, 2011, 12:23pm

@J,
Thank you for the confirmation.

@Simon,
I see. Thank you for the information.

@all,
Now then, I have two more questions.

1st:
“Windows does not use X.” … I see.
But can I use xid on Windows or can’t?

I ran the following snippet on my Windows 7 and I got a xid for a video
window created by playbin2 plugin.

require ‘gtk2’
require ‘gst’
play_bin = Gst::ElementFactory.make(‘playbin2’)
bus = play_bin.bus
bus.add_watch do |bus, message|
case message.type
when Gst::Message::ELEMENT
p message.structure[“xwindow-id”] #=> Got a number, e.g. 18023540
end
true
end
play_bin.uri = ‘file://d/tmp/input.mp4’
window = Gtk::Window.new
window.show_all
play_bin.play
Gtk.main

2nd: If the above first questions’s answer is “can’t”,
are there any alternative ways to identify a window on Windows?
A native window handler or somthing…

I’m now looking for the way to embed the video window in my Ruby/GTK2
application.
I found GstXOverlay[*1]. So, I want to know how to identify a window.

ashbb

*1:
http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-libs/html/gst-plugins-base-libs-gstxoverlay.html#GstXOverlay

satoshi_a · October 4, 2011, 2:10am

hi ashbb,

maybe this could help?

FindWindowA function (winuser.h) - Win32 apps | Microsoft Learn

i don’t know if the handle returned by the FindWindow function relates
in any way to the value returned by the GstStructure, but maybe?
hopefully

j

satoshi_a · October 3, 2011, 3:04pm

Satoshi A. wrote in post #1024748:

1st:
“Windows does not use X.” … I see.
But can I use xid on Windows or can’t?

You can’t. The source is :
#ifdef GDK_WINDOWING_X11
rb_define_method(gdkDrawable, “xid”, gdkdraw_get_xid, 0);
#endif

And, as I said, windows does not use X.

I ran the following snippet on my Windows 7 and I got a xid for a video
window created by playbin2 plugin.

require ‘gtk2’
require ‘gst’
play_bin = Gst::ElementFactory.make(‘playbin2’)
bus = play_bin.bus
bus.add_watch do |bus, message|
case message.type
when Gst::Message::ELEMENT
p message.structure[“xwindow-id”] #=> Got a number, e.g. 18023540
end
true
end
play_bin.uri = ‘file://d/tmp/input.mp4’
window = Gtk::Window.new
window.show_all
play_bin.play
Gtk.main

You do not get a ‘xid’, you retrieve a value from a GstStructure, with
the key ‘xwindow-id’. I don’t know how GStreamer fills this value.

2nd: If the above first questions’s answer is “can’t”,
are there any alternative ways to identify a window on Windows?
A native window handler or somthing…

I’m now looking for the way to embed the video window in my Ruby/GTK2
application.
I found GstXOverlay[*1]. So, I want to know how to identify a window.

I think GstXOverlay is only for X too, but I don’t know much GStreamer.

This discussion Gstreamer: linking playbin2 - Ruby-Gnome 2 - Ruby-Forum talks about
that, and it seems no solution was found.

I’m not sure you will be able to do what you want with ruby.

Simon

satoshi_a · October 4, 2011, 1:22pm

Hi J, Simon at al,

Win32API- GetForegroundWindows() - Ruby - Ruby-Forum
Wow, bingo!

Try out the following. The video is embedded in my Ruby/GTK2 app window!

require ‘gtk2’
require ‘gst’
require ‘win32api’
play_bin = Gst::ElementFactory.make(‘playbin2’)
play_bin.uri = ‘file://d/tmp/input.mp4’
play_bin.video_sink = Gst::ElementFactory.make(‘dshowvideosink’)
window = Gtk::Window.new
window.signal_connect(‘expose-event’)do
play_bin.video_sink.xwindow_id = Win32API.new(‘user32’,
‘GetForegroundWindow’, [], ‘N’).call
end
window.show_all
play_bin.play
Gtk.main

Thanks,
ashbb