Designing gtk+ applications

Desktop Ruby-Gnome 2
1

Hi guys, I’d like to consult with you about the following:
is it possible to customize design of GTK+ apps? I mean they use system
theme’s settings by default(the same width, color, transparency etc.),
but I’d like my application to look as I want. I’ve almost created my
mp3 player, but it’s look kills me. What should I do to use my own
design features?

Best,
Roman.

2

write web apps.

3

yeah, you can’t change the theme of a gtk app without changing the whole
system theme.

On Thu, Jul 1, 2010 at 1:49 PM, niklas | brueckenschlaeger <

4

It’s possible, but not encouraged.

Take the following, for example - it demonstrates the parsing of an
additional theme file, local modification of settings that are otherwise
shared and overriding the drawing of a particular widget.

–8<—
#!/usr/bin/ruby
vanilla = fork()

require ‘gtk2’

window = Gtk::Window.new

window.set_border_width(16)
window.add(button = Gtk::Button.new(“Text”))
button.children[0].set_padding(16,16)

unless vanilla

Parse custom gtkrc

Gtk::RC.parse_string <<-RC
style “displace”
{
GtkButton::child_displacement_y = 8
GtkButton::child_displacement_x = 8
}
class “GtkButton” style “displace”
RC

Modify local gtk settings, ie. theme

Gtk::Settings.default.gtk_theme_name = “HighContrastInverse”

Paint the button using cairo instead of theme

button.set_app_paintable(true)
button.signal_connect(‘expose-event’) do |widget,e|
cr = widget.window.create_cairo_context

xmod, ymod = widget.style_get_property(‘child-displacement-x’),
widget.style_get_property(‘child-displacement-y’)
allocation = widget.allocation

if widget.state == Gtk::STATE_ACTIVE
x, y, w, h = allocation.x + 2xmod, allocation.y + 2ymod,
allocation.width - 2xmod, allocation.height - 2ymod
else
x, y, w, h = allocation.x + xmod, allocation.y + xmod,
allocation.width - 2xmod, allocation.height - 2xmod
cr.save do
cr.translate(xmod, ymod)
cr.rounded_rectangle(x, y, w, h, 16)
cr.set_source_rgba(0.6,0.2,0.2,0.8)
cr.fill
end
end
cr.rounded_rectangle(x, y, w, h, 16)
cr.set_source_rgba(0.5,0.5,0.5,0.8)
cr.fill

Propagate expose event to child widgets

widget.children.each { |child| widget.propagate_expose(child, e) }

Block default expose-event handler

true
end

end

window.show_all

Gtk.main
–8<–

5

It is not that wery hard to write your own widgets.

If you want VERY fancy widgets you can also use Cairo.
Take a look at

http://www.raditex.nu//websvn/listing.php?repname=kurssrc.Exempel&path=%2FCairoCandy%2F#_CairoCandy_

Gorhas

2010/7/1 Grant McLean [email protected]

6

On Thu, 2010-07-01 at 14:30 +0200, Roman Tolmachev wrote:

Hi guys, I’d like to consult with you about the following:
is it possible to customize design of GTK+ apps? I mean they use system
theme’s settings by default(the same width, color, transparency etc.),
but I’d like my application to look as I want. I’ve almost created my
mp3 player, but it’s look kills me. What should I do to use my own
design features?

When you need to step outside the standard set of GTK user interface
elements, one approach is to use a canvas widget. The GNOME canvas is
certainly one option and I think the Ruby bindings should work. Be
warned that the GNOME canvas has been deprecated upstream but as yet no
clear replacement has emerged.

Recently I’ve been doing some work with the Clutter canvas which is very
good. I have no idea about the availability of Ruby bindings for
Clutter though as I’ve mostly been working with Perl.

Cheers
Grant