Gtk+ is a cross-platform GUI toolkit created for the development of the GIMP project. Offering a complete set of widgets, Gtk+ is suitable for projects ranging from small one-off tools to complete applications suites.
For C programming with Gtk+ you need to install the development version of the important GNOME libraries. Those contain the header files and additional linker information:
$ sudo dnf install gtk3-devel gstreamer1-devel clutter-devel webkit2gtk3-devel libgda-devel gobject-introspection-devel
In addition, you will want to install the documentation packages of the libraries so you can view them in the API browser (devhelp):
$ sudo dnf install devhelp gtk3-devel-docs clutter-doc
To begin our introduction to Gtk+, we will start with the simplest program possible. This program will simply create a gtk+ window with the title “Hello World”.
#include <gtk/gtk.h>
int
main(int argc,
char *argv[])
{
GtkWidget *window;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "Hello World");
gtk_widget_show (window);
gtk_main ();
return 0;
}
You can compile the above program with gcc using:
$ gcc hello.c -o hello `pkg-config --cflags --libs gtk+-3.0`
In the program above we initially included gtk/gtk.h, which declares all the gtk+ objects used in the rest of the program:
#include <gtk/gtk.h>
or
#include <gtk-3.0/gtk/gtk.h>
After the declaration of the window object variable, we call the gtk_init method which initializes the library and its internal procedures.
gtk_init (&argc, &argv);
The next line creates a GtkWindow object with the GTK_WINDOW_TOPLEVEL type. Nearly always, that’s the type of the GtkWindow, but it could differ if you are implementing something else.
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
Below that, we set the title of the GtkWindow to a string of our choice:
gtk_window_set_title (GTK_WINDOW (window), "Hello World");
After that, the gtk_widget_show() function lets Gtk+ know that we are done setting the attributes of this widget, and that it can display it.
gtk_window_show (window);
Finally, the last line enters the Gtk+ main processing loop.
gtk_main ();
Authors: Andy Holmes, Carlo Lobrano, Gabe Ron, Jarek Prokop, Nick Dirschel