Is it possible to use menus created with Glade in gtk2hs?

Question

I have menus created with Glade in my gtk2hs application. Is it possible to use this in my Haskell code to write actions for each activated menu item? Is there a simple example somewhere or project on Hackage that can be used as an illustrative example?

The only menu example I was able to find http://www.muitovar.com/gtk2hs/chap7-1.html does not seem to help to work with Gtk Builder XML.

Answer 1

Here two examples from an application of mine. In main, I bind the GTK widgets to variables and those to callback functions that I implement in other modules.

--To load the Glade file:

gui <- builderNew
builderAddFromFile gui "myGUI.glade"

-- To close the application:

-- bind the window "mainWindow" (defined in the Glade file) to a variable

mainWindow <- builderGetObject gui castToWindow "mainWindow"

-- bind the menu item "menu_Quit" (defined in the Glade file) to a variable

mQuit <- builderGetObject gui castToMenuItem "menu_Quit"

-- bind the menu item to the GTK function "widgetDestroy"

on mQuit menuItemActivate $ widgetDestroy mainWindow

-- bind mainWindow's event "objectDestroy" to the GTK function "mainQuit"

on mainWindow objectDestroy mainQuit

-- To call a function when the user selects another menu item, say "menu_About":

-- bind the menu item to a variable

mAbout <- builderGetObject gui castToMenuItem "menu_About"

-- make the menu item show the About Dialog (defined in the Glade file)

on mAbout menuItemActivate $ do
    aboutDialog <- builderGetObject gui castToDialog "aboutDialog"
    set aboutDialog [ widgetVisible := True ]
    dialogRun aboutDialog
    set aboutDialog [ widgetVisible := False ]

You could place the do block in a function, maybe in a module where you define all your responses to GTK events:

showAboutDialog :: Builder -> IO ()
showAboutDialog gui = [insert do block here]

Then you could substitute the do block after menuItemActivate with just:

on mAbout menuItemActivate $ showAboutDialog gui

Note that I pass the Builder object to showAboutDialog because that function needs to get the dialog from the Glade file.