GDK#create_cairo_context not found

[Farrel Lifson]

What version of rcairo, and ruby-gnome2 do I need to have
GDK#create_cairo_context? I get the following error

demo.rb:23:in `expose': undefined method `create_cairo_context' for
#<Gdk::Window:0xb724dd28 ptr=3D0x82bb290> (NoMethodError)
from demo.rb:13:in `initialize'
from demo.rb:74

when trying to run the following sample code:
#!/usr/bin/env ruby

require 'cairo'
require 'gtk2'
include Math

class DemiCercle < Gtk:rawingArea
attr_accessor :desp
def initialize
super
add_events(Gdk::Event::BUTTON_PRESS_MASK |
Gdk::Event::BUTTON1_MOTION_MASK)
signal_connect "expose_event" do |widget,event|
expose(widget,event)
end # do
signal_connect "button_press_event" do |widget,event|
pressing(widget,event) end
signal_connect "motion_notify_event" do |widget,event|
moving(widget,event) end

@desp =3D 0.0
end # initialize

def expose(widget,event)
# cr=C3(c)er un contexte graphique
context =3D widget.window.create_cairo_context

context.rectangle(event.area.x, event.area.y,
event.area.width, event.area.height)

context.clip()
draw(context)
return false
end # expose

def draw(context)
rect =3D allocation()
x =3D rect.x + rect.width / 2.0
y =3D rect.y + rect.height / 2.0

radius =3D [rect.width / 2.0, rect.height / 2.0].min - 5.0

#context.arc(x, y, radius, 0,(1 * PI))
context.arc(x, y, radius, 0 + @desp , (1.0 * PI) + @desp)

context.set_source_rgb(0.7, 0.8, 0.1)
context.fill_preserve()

context.set_source_rgb(0, 0, 0)
context.stroke()
end

def pressing(widget,event)
pressing_x =3D event.x
end

def moving(widget,event)
if (pressing(widget,event) - event.x) > 1
@desp =3D @desp + 0.2
else
@desp =3D @desp - 0.1
end
draw(widget.window.create_cairo_context)
queue_draw()
end
end


Gtk.init
fen =3D Gtk::Window.new
fen.set_title("Cairo exemple 2")
fen.signal_connect("destroy") { Gtk.main_quit }
figure =3D DemiCercle.new
fen.add(figure)
fen.show_all

Gtk.main

I have the following libs installed on my Gentoo box:

nicodemus portage # emerge -p rcairo gtk+ ruby-gnome2
Calculating dependencies... done!
[ebuild R ] dev-ruby/rcairo-1.0.0 USE=3D"-examples*"
[ebuild R ] x11-libs/gtk+-2.8.12 USE=3D"-tiff*"
[ebuild R ] dev-ruby/ruby-gnome2-0.14.1

Thank,
Farrel

 

[anne001]

do you get the same error in irb when you type
require 'cairo'

cairo has a list and they may be able to help,

If you have trouble with cairo or rcairo, or you have some ideas for
how
it could be improved, please feel free to send a message to the cairo
mailinglist at (e-mail address removed) , which is archived at

http://cairographics.org/cgi-bin/mailman/listinfo/cairo

a post from
http://lists.freedesktop.org/archives/cairo/2006-April/006663.html
refers to
Gdk:rawable::create_cairo_context()

 

[Farrel Lifson]

do you get the same error in irb when you type
require 'cairo'

Nope cairo loads fine. It just seems that the GDK:rawable object
seems to be missing the create_cairo_context method. According to the
documentation I've read that code should work with GTK 2.8,
Ruby/Gnome2 0.14 and rcairo 1.0 all of which I have installed. I've
recompiled and re-installed everything but that didn't work. I just
want to make sure that I'm using the correct versions or if I'm not
missing some other required library.

Thanks,
Farrel

 

[Masao Mutoh]

Hi,

Your sample works on my machine.

I suspect you didn't install Ruby/Cairo devel package.

Check /usr/(local/)lib/ruby/site_ruby/1.8/i686-linux/rb_cairo.h.
If it's not existed, you need to install Ruby/Cairo dev package
first. Then compile Ruby-GNOME2 again.

If you are't be able to fix it,
show me your ruby-gnome2-x.x.x/gtk/mkmf.log.

 

[Farrel Lifson]

Hi,

Your sample works on my machine.

I suspect you didn't install Ruby/Cairo devel package.

Check /usr/(local/)lib/ruby/site_ruby/1.8/i686-linux/rb_cairo.h.
If it's not existed, you need to install Ruby/Cairo dev package
first. Then compile Ruby-GNOME2 again.

If you are't be able to fix it,
show me your ruby-gnome2-x.x.x/gtk/mkmf.log.

Hi,

I solved the problem I had to re-install the ruby/gtk2 bindings after
I had installed rcairo.

Thanks for the help,
Farrel

 

[anne001]

With a little help, I managed to compile cairo on my OS X such that irb
can include cairo without error message. So now, I get the same error
message as Farrel

I checked on rb_cairo.h, it is in
/private/opt/local/lib/ruby/site_ruby/1.8/powerpc-darwin8.3.0/rb_cairo.h

The person who helped me with my cairo installed thought that the
problem was with my having an old gnome2, but the darwinport folder
said ruby-gnome2-all-0.15.0. he thought 0.15.0 was alright.

he suggested getting help at
http://lists.sourceforge.net/mailman/listinfo/ruby-gnome2-devel-en

I found the ruby-gnome2-all-0.15.0/gtk/mkmf.log, I posted it at
visionlab.harvard.edu/Members/Anne/mkmf.log

 

[anne001]

So it is an install problem.

I was interested, because I wanted to know if my gnome2 install was ok,
I guess not. I tried recompiling all the rb files, but that did not
change anything for me. glib2, atk, cairo, pango and then gtk, but I
still have the error. Oh well.

 

[Farrel Lifson]

So it is an install problem.

I was interested, because I wanted to know if my gnome2 install was ok,
I guess not. I tried recompiling all the rb files, but that did not
change anything for me. glib2, atk, cairo, pango and then gtk, but I
still have the error. Oh well.

It helped me that I built ruby/gtk2 after I had installed rcairo.

Farrel

 

[Masao Mutoh]

Hi,

With a little help, I managed t/private/opt/local/lib/ruby/site_ruby/1.8/powerpc-darwin8.3.0o compile cairo on my OS X such that irb
can include cairo without error message. So now, I get the same error
message as Farrel

I checked on rb_cairo.h, it is in
/private/opt/local/lib/ruby/site_ruby/1.8/powerpc-darwin8.3.0/rb_cairo.h

The person who helped me with my cairo installed thought that the
problem was with my having an old gnome2, but the darwinport folder
said ruby-gnome2-all-0.15.0. he thought 0.15.0 was alright.

he suggested getting help at
http://lists.sourceforge.net/mailman/listinfo/ruby-gnome2-devel-en

I found the ruby-gnome2-all-0.15.0/gtk/mkmf.log, I posted it at
visionlab.harvard.edu/Members/Anne/mkmf.log

It seems no problem from your mkmf.log.
rb_cairo.h was found in it correctly.

You need to tell us more informations.
1. What is the result of require 'cairo' ?
$ irb
irb(main):001:0> require 'cairo'
=> true

2. Try to remove /private/opt/local/lib/ruby/site_ruby/1.8/.../gtk2.so
once, then,
$ cd ruby-gnome2-x.x.x/gtk
$ make clean
$ ruby extconf.rb >& log.txt
$ make >>& log.txt
$ make install >>& log.txt

Then, if your problem is not fixed, send me your log.txt.

 

[anne001]

1. What is the result of require 'cairo' ?

$ irb
irb(main):001:0> require 'cairo'
=> true

that is correct

2. Try to remove /private/opt/local/lib/ruby/site_ruby/1.8/.../gtk2.so

I can't find such a file with EasyFind. On the web I see references to
/usr/local/lib/ruby/site_ruby/1.8/i386-freebsd4/gtk2.so
site_ruby/1.8/i586-linux-gnu/gtk2.so
site_ruby/1.8/i586-linux/gtk2.so
usr/lib/ruby/1.8/i386-linux/gtk2.so

ls /private/opt/local/lib/ruby/site_ruby/1.8 anne$ ls
#hhp-access2.rb# gtk2 pango.rb
atk.rb gtk2.rb pkg-config.rb
cairo.rb gtkglext.rb powerpc-darwin8.3.0
gconf2.rb gtkhtml2.rb soap
gdk_pixbuf2.rb http-access2 universal-darwin8.0
glib2.rb http-access2.rb web
gnome2.rb http-access2.rb~ web.rb
gnomecanvas2.rb libglade2.rb wsdl
gnomevfs.rb mkmf-gnome2.rb xmlscan

powerpc-darwin8.3.0 has bundles and .h files.

 

[Masao Mutoh]

Hi,

that is correct


I can't find such a file with EasyFind. On the web I see references to

You must have "gtk2.so" anywhere. Find it and remove all of "gtk2.so".

 

[anne001]

from what I read .so is an extension for a shared library.

The extension for a shared library on Mac OS X is .dylib, so this
shared library is named mymfunction.dylib on Mac OS X. This book uses
..so as the extension for UNIX shared libraries, so Mac OS X users need
to use the proper extension.

http://www.mathworks.com/access/helpdesk/help/toolbox/compiler/f5-51556.html

there are a number of dylib files with gtk in it:

/private/opt/local/lib anne$ ls libgtk*
libgtk-1.2.0.9.1.dylib libgtkglext-x11-1.0.0.2.4.dylib
libgtk-1.2.0.dylib libgtkglext-x11-1.0.0.dylib
libgtk-x11-2.0.0.800.16.dylib libgtkglext-x11-1.0.a
libgtk-x11-2.0.0.dylib libgtkglext-x11-1.0.dylib
libgtk-x11-2.0.dylib libgtkglext-x11-1.0.la
libgtk-x11-2.0.la libgtkhtml-2.0.0.0.dylib
libgtk.1.dylib libgtkhtml-2.0.dylib
libgtk.a libgtkhtml-2.a
libgtk.dylib libgtkhtml-2.dylib
libgtk.la libgtkhtml-2.la

I tried recompiling by hand, starting with gettext glib, etc. I
download the gettext source, and the configure, make of gettext gave an
error, so I posted my problem to the ruby gettext list in case that is
part of my trouble.

 

[anne001]

Victory!!!!

Thank you so much for explaining to me that ruby-gettext has nothing to
do with gettext, ruby-gnome2 has nothing to do with gnome2. That set my
mind free to only worry about my ruby installation.

I uninstalled ruby, and all other darwin ports, reinstalled them,
reinstalled rubygems, installed the gettext gem, installed the gtk
files one by one, making sure the dependencies were ok.

and this little program works! Amazing.