Gtk Button

Zlatan_ · **Joined:** Fri Dec 09, 2011 6:25 pm **Posts:** 12

First topic. I'm new to GTK.
I'm doing a C++ project with Gtk.
I have to put a button in a frame. I would like to know if it is possibile to to put the button not in the centre and with th size that I want inside the frame.
How can i do it?

Code:

vbox = gtk_vbox_new (FALSE, NULL);
   
gtk_container_add (GTK_CONTAINER (window), vbox);

menubar = gtk_menu_bar_new ();
gtk_box_pack_start (GTK_BOX (vbox), menubar, FALSE, FALSE, NULL);

hbox = gtk_hbox_new (FALSE, NULL);
gtk_box_pack_start (GTK_BOX (vbox), hbox, TRUE, TRUE, NULL);

frame = gtk_frame_new (NULL);
gtk_frame_set_label_align (GTK_FRAME (frame), 0.0, 0.0);
gtk_frame_set_shadow_type( GTK_FRAME(frame), GTK_SHADOW_ETCHED_OUT);
   
gtk_box_pack_start (GTK_BOX (hbox), frame, TRUE, TRUE, NULL);
   

button = gtk_button_new_with_label ("Load map");
gtk_box_pack_start (GTK_BOX (frame), button, TRUE, TRUE, NULL);

drawing_area = gtk_drawing_area_new ();
gtk_drawing_area_size (GTK_DRAWING_AREA (drawing_area), 600, 400);
gtk_box_pack_start (GTK_BOX (hbox), drawing_area, TRUE, FALSE, NULL);

of course i've created and packed the Main window

errol · **Posted:** Fri Dec 09, 2011 7:16 pm

Hi,

What you need to do (I think 8-) ) is add the lines

Code:

  gtk_widget_set_halign(button, GTK_ALIGN_CENTRE);
  gtk_widget_set_valign(button, GTK_ALIGN_CENTRE);

This will place the button in the centre at its natural size, there are other alignment options. You may also want to set the flags when packing the button to not expand and fill.

Also not that the final argument to gtk_box_pack_start() is an integer and not a pointer. So you should not be using NULL.

Code:

// Bad code
  gtk_box_pack_start(GTK_BOX(hbox), frame, TRUE, TRUE, NULL);

//Good code
  gtk_box_pack_start(GTK_BOX(hbox), frame, TRUE, TRUE, 0);

Zlatan_ · **Joined:** Fri Dec 09, 2011 6:25 pm **Posts:** 12

thank you, but adding your 2 lines I have got problems..

Code:

error: ‘GTK_ALIGN_CENTRE’ was not declared in this scope
error: ‘gtk_widget_set_halign’ was not declared in this scope
error: ‘gtk_widget_set_valign’ was not declared in this scope

I use

Code:

#include <gtk/gtk.h>

and I also tried

Code:

#include <sdl/sdl.h>

but I still haven't found a solution.
I need to put the button at the center put on the top of the frame (for ex if I can divide the frame in 3 parts, i'll put the button in the 1st part).
Is it possible also to change the size of the frame? Or to put the button in the hbox instead than in the frame?

I compile with

Code:

g++ -Wall -O3 `pkg-config --libs --cflags gtk+-2.0` -o prog prog.cc

errol · **Posted:** Fri Dec 09, 2011 9:03 pm

You did not say which version of GTK you were using, so I used the latest which is version 3. gtk_widget_set_halign() and gtk_widget_set_valign() are in GTK version 3 and not in 2 which I now see that is what you are using.

Note SDL has nothing to do with GTK.

You can place a Button into any container, so yes you can place it into a HBox.

Zlatan_ · **Joined:** Fri Dec 09, 2011 6:25 pm **Posts:** 12

ok! does gtk 3 work with ubuntu 10.04?

Code:

gtk_widget_set_halign (button, GTK_ALIGN_CENTRE);
     gtk_widget_set_valign (button, GTK_ALIGN_CENTRE);

how are they called in gtk2?

zerohour · **Posted:** Fri Dec 16, 2011 1:48 am

You said you're doing a C++ project, GTK for C++ is called Gtkmm. http://www.gtkmm.org/en/
Does Gtk work with 10.04, http://blog.sudobits.com/2010/06/01/how-to-install-gtk-in-ubuntu-10-04/
If you want to stick with C code, use Gtk3 and also install libgtk-3-doc (Documentation for the GTK+ graphical user interface library) and study it. But you can always look at the documentation online. If you want to stick with Gtk2, I believe this is the newest documentation version. http://developer.gnome.org/gtk/2.24/
Since I've upgrade to gtk3 I've got the documentation for both gtk2 and gtk3. gtk_widget_set_valign is only in Gtk3. http://developer.gnome.org/gtk3/stable/GtkWidget.html#gtk-widget-set-valign I would also suggest you install Glade along with libgtk-3-doc. I don't use Glade to design interfaces, It's just great way to look up properties. Once you add a widget, you can just right click and select "Read Documentation" which will take you to the associated documentation page.
Also have a look in the tutorials sections here in the forums. I've posted some Gtk3 examples with CSS for styling and I use gtk_widget_set_valign.

Zlatan_ · **Joined:** Fri Dec 09, 2011 6:25 pm **Posts:** 12

nice!
I've done a lot of improvements now. Thank you very much. When I try to install GTK+3 using the package from http://www.gtk.org/download/linux.php I have a lot of problems.
I'm on Ubuntu 10.04 trying to install GTK+ 3. First of all i have to install atk, gdk-pixbuf, pango and glib.
I try to install atk and i get

Code:

atktext.c:1433: error: expected declaration specifiers or ‘...’ before ‘atk_text_range’
atktext.c:1433: error: expected declaration specifiers or ‘...’ before ‘atk_text_range_copy’
atktext.c:1434: error: expected declaration specifiers or ‘...’ before ‘atk_text_range_free’
atktext.c:1434: warning: return type defaults to ‘int’
atktext.c: In function ‘G_DEFINE_BOXED_TYPE’:
atktext.c:1433: error: parameter name omitted
atktext.c:1434: error: expected ‘{’ at end of input
make[3]: *** [atktext.lo] Errore 1
make[3]: uscita dalla directory «/home/cristiano/Desktop/atk-2.0.1/atk»
make[2]: *** [all] Errore 2
make[2]: uscita dalla directory «/home/cristiano/Desktop/atk-2.0.1/atk»
make[1]: *** [all-recursive] Errore 1
make[1]: uscita dalla directory «/home/cristiano/Desktop/atk-2.0.1»
make: *** [all] Errore 2

Somebody knows why?

zerohour · **Posted:** Mon Dec 19, 2011 3:57 am

What version of GTK and ATK are you trying to install ?

GTK3 has minimum version requirements for each package and some packages in turn have their own requirements so read the INSTALL and README file for each one.
For instance: If your installing the Gtk+-3.2.3, the INSTALL says:
GTK+ 3.2.3 requires at least:
GLib 2.29.14
Pango 1.29.0
GdkPixbuf 2.23.5
ATK 2.1.5
cairo 1.10.0.
gobject-introspection 0.10.1

What order are you installing the dependencies ? http://developer.gnome.org/gtk3/stable/gtk-building.html

You could just install Ubuntu 11.10 (Oneiric Ocelot) It has Gtk+-3.2.0 and Glade 3.10.0 in packages so it's an automadated install. But I don't reccommend using Software Center to install anything. Use Synaptic package manager and install Glade. That should install everything you need. But Synaptic doesn't come with Ubuntu 11.10, you have to install it: sudo apt-get install synaptic
Then run gnome classic: sudo apt-get install gnome-session-fallback
http://linux-software-news-tutorials.bl ... y-and.html

Note: I believe there's a bug in gtk+-3.2.0 and CSS with Ubuntu 11.10, but maybe it's just my system.

GTK+ Forums

Gtk Button

Who is online