1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
program %{APPNAMELC};
{$mode objfpc}
uses
glib,gdk,gtk;
procedure hello(widget : pGtkWidget ; data: pgpointer ); cdecl;
begin
writeln('Hello World');
end;
function delete_event (widget : pGtkWidget ; event: pGdkEvent; data: pgpointer ): integer; cdecl;
begin
writeln('Delete Event Occurred');
delete_event := ord(true);
end;
procedure destroy(widget : pGtkWidget ; data: pgpointer ); cdecl;
begin
gtk_main_quit();
end;
var
window, button : pGtkWidget;//GtkWidget is the storage type for widgets
begin
// This is called in all GTK applications. Arguments are parsed
// from the command line and are returned to the application.
gtk_init (@argc, @argv);
// create a new window
window := gtk_window_new (GTK_WINDOW_TOPLEVEL);
// When the window is given the "delete_event" signal (this is given
// by the window manager, usually by the 'close' option, or on the
// titlebar), we ask it to call the delete_event () function
// as defined above. The data passed to the callback
// function is NULL and is ignored in the callback function.
gtk_signal_connect (pGTKOBJECT (window), 'delete_event',
GTK_SIGNAL_FUNC (@delete_event), NIL);
// Here we connect the "destroy" event to a signal handler.
// This event occurs when we call gtk_widget_destroy() on the window,
// or if we return 'FALSE' in the "delete_event" callback.
gtk_signal_connect (pGTKOBJECT (window), 'destroy',
GTK_SIGNAL_FUNC (@destroy), NULL);
// Sets the border width of the window.
gtk_container_set_border_width (GTK_CONTAINER (window), 10);
// Creates a new button with the label "Hello World".
button := gtk_button_new_with_label ('Hello_World');
// When the button receives the "clicked" signal, it will call the
// function hello() passing it NULL as its argument. The hello()
// function is defined above. */
gtk_signal_connect (pGTKOBJECT (button), 'clicked',
GTK_SIGNAL_FUNC (@hello), NULL);
// This will cause the window to be destroyed by calling
// gtk_widget_destroy(window) when "clicked". Again, the destroy
// signal could come from here, or the window manager
gtk_signal_connect_object (pGTKOBJECT (button), 'clicked',
GTK_SIGNAL_FUNC (@gtk_widget_destroy),
pGTKOBJECT(window));
// This packs the button into the window (a gtk container).
gtk_container_add (GTK_CONTAINER (window), button);
// The final step is to display this newly created widget.
gtk_widget_show (button);
// and the window
gtk_widget_show (window);
// All GTK applications must have a gtk_main(). Control ends here
// and waits for an event to occur (like a key press or
// mouse event).
gtk_main ();
end.
|
