goroutines.go won't build

[mark-summerfield]

On both Ubuntu 22.04 and Debian 11 running Go 1.19 from the binary installer, the goroutines.go fails to build:

# gtk-examples/goroutines
./goroutines.go:70:14: assignment mismatch: 2 variables but glib.IdleAdd returns 1 value
./goroutines.go:70:45: too many arguments in call to glib.IdleAdd
    have (func(label *gtk.Label, text string) bool, *gtk.Label, string)
    want (interface{})
./goroutines.go:76:13: assignment mismatch: 2 variables but glib.IdleAdd returns 1 value
./goroutines.go:76:47: too many arguments in call to glib.IdleAdd
    have (func(str string), string)
    want (interface{})

If fixed this by changing the anonymous goroutine as follows:

    go func() {
        for {
            time.Sleep(time.Second)
            s := fmt.Sprintf("Set a label %d time(s)!", nSets)
            handle := glib.IdleAdd(func() bool {
                return LabelSetTextIdle(topLabel, s)
            })
            log.Printf("IdleAdd() #1 handle=%T %v\n", handle, handle)
            nSets++
            s = fmt.Sprintf("Set a label %d time(s)!", nSets)
            handle = glib.IdleAdd(func() bool {
                bottomLabel.SetText(s)
                return false
            })
            log.Printf("IdleAdd() #2 handle=%T %v\n", handle, handle)
            nSets++
        }
    }()

The returned value is a "SourceHandle"; I don't know that that is or means since I'm only just starting with Go/Gtk.