“Hello Glade#” from F#

Another bit of spiking, a rather tardy follow up from raw GTK#, starting from the C# example at the Mono Project site, but incorporating the earlier example, so as to build in a clean application exit, for one thing.

In the .glade file, I changed the label size from 38, as in

<widget class="GtkLabel" id="label1">
       <property name="width_request">38</property>

to 88, so as to allow the displayed text to be longer.

In VS2008 I added the .glade file by including a new F# script file, but renaming it to gui.glade, pasting in the XML, and setting its properties to have a Build Action of Embedded Resource. The code looks like:

	open System
	open Gtk
	open Glade
	let mutable click_count = 0
	type Handler() = class
	[<Widget>]
	[<DefaultValue(true)>]
	val mutable button1 : Button
	[<Widget>]
	[<DefaultValue(true)>]
	val mutable label1 : Label
	[<Widget>]
	[<DefaultValue(true)>]
	val mutable window1 : Window
	end
	let OnClick (h : Handler) =
	//h.label1.Text <- "Mono" -- original example's code
	click_count <- click_count + 1
	// Console.WriteLine("Button Click {0}", click_count)
	h.label1.Text <- String.Format("Button Click {0}", click_count)
	let OnDelete (args:DeleteEventArgs) =
	Application.Quit()
	args.RetVal <- true
	[<EntryPoint>]
	let main a =
	Application.Init()
	// Developed with Glade 3.8.3 http://ftp.gnome.org/pub/GNOME/binaries/win32/glade/3.8/glade-3-8-3-installer.exe
	// Needs libglade project file format
	let gxml = new Glade.XML (null, "gui.glade", "window1", null)
	let handler = new Handler()
	gxml.Autoconnect (handler)
	handler.button1.Clicked
	|> Event.add (fun _ -> OnClick handler)
	handler.window1.DeleteEvent
	|> Event.add OnDelete
	handler.window1.ShowAll()
	Application.Run()
	0 // needs an int return

view raw Program.fs hosted with ❤ by GitHub

Here the widgets are surfaced via a plain data object, Handler, and their events are wired up much as before via F#'s first class reactive events, which are much more natural (especially when combining events to one handler is required). The project needs a reference to the glade-sharp assembly, above and beyond the ones already required for pure GTK#

Unfortunately, the need for CLR attributes on members is problematic for IronPython -- the least nasty way to achieve the equivalent of the Handler class would be to compile some C# on the fly.

Unchanged by version 1.9.9.9, February 2010 CTP.

Unchanged by version 3.1.1, January 2014 (except that Add Existing Item works better for the .glade file in VS2010 and up).