verticalbox.c

#include <gtk/gtk.h>

																				//compile with gcc -Wall -g window.c -o window `pkg-config --cflags --libs gtk+-3.0`
void callback(void);                                                            //user function declaration  
int main(int argc, char *argv[])
{
	GtkWidget *window;															//this declares windows as type GtkWidget*
	GtkWidget *button;                                                          //this declares the button as type GtkWidget*
	GtkWidget *vbox;                                                            //this will be used for our vertical box.
	gtk_init(&argc, &argv);														//this initializes gtk

window = gtk_window_new(GTK_WINDOW_TOPLEVEL); 									//gtk_window_new() sets the widget to type GtkWindow* it takes one parameter which is the window type. 
											  									//the 2 window types are GTK_WINDOW_TOPLEVEL and GTK_WINDOW_POPUP. 
gtk_window_set_title(GTK_WINDOW(window), "New Window"); 						//sets a window title. gtk_window_set_title takes the 2 parameters,
																				//GtkWindow *window and const gchar *title 
gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); 				//opens the window in the center of the screen, this function takes 2 parameters, 
																 				//the parameters are GtkWindow* and GtkWindowPosition.

gtk_container_set_border_width(GTK_CONTAINER(window), 5); 						//sets the border width of the window, this takes 2 parameters, the GtkWidget* and the width respectively.

g_signal_connect(G_OBJECT(window), "destroy",G_CALLBACK(gtk_main_quit), NULL);  //this line add the callback for the window to be closed when you click the x in the corner
 									  											//the function g_signal_connect is defined as g_signal_connect(instance, detailed_signal, c_handler, data)
									   											//you will see more examples of this in coming tutorials 

vbox = gtk_box_new(GTK_ORIENTATION_VERTICAL, 1); //creates a vbox without autosizing 
for (int i = 0; i<5; i++)
{
button = gtk_button_new_with_label("This is a button");                         //creates a new button with a label
g_signal_connect(button, "clicked", G_CALLBACK(callback), NULL);                //attaches the callback to the button 
gtk_box_pack_start(GTK_BOX(vbox), button, FALSE, FALSE, 0);            //packs the buttons into the vertical box
}
gtk_container_add(GTK_CONTAINER(window), vbox);                                 //adds the button to the window 
gtk_widget_show_all(window); 													//shows all widgets within the GtkWidget *window; this function takes one parameter with the data type GtkWidget

gtk_main();																		//gtk main is a void function, this is the main loop of GTK. 
}

void callback(void)                                                             //button callback, prints to the console that you clicked the button.
{
	g_print("you clicked the button!");
}