func main() {
gtk.Init(nil)
win, err := gtk.WindowNew(gtk.WINDOW_TOPLEVEL)
if err != nil {
log.Fatal("Unable to create window:", err)
}
win.Connect("destroy", func() {
gtk.MainQuit()
})
win.Add(windowWidget())
// Native GTK is not thread safe, and thus, gotk3's GTK bindings may not
// be used from other goroutines. Instead, glib.IdleAdd() must be used
// to add a function to run in the GTK main loop when it is in an idle
// state.
//
// Two examples of using glib.IdleAdd() are shown below. The first runs
// a user created function, LabelSetTextIdle, and passes it two
// arguments for a label and the text to set it with. The second calls
// (*gtk.Label).SetText directly, passing in only the text as an
// argument.
//
// If the function passed to glib.IdleAdd() returns one argument, and
// that argument is a bool, this return value will be used in the same
// manner as a native g_idle_add() call. If this return value is false,
// the function will be removed from executing in the GTK main loop's
// idle state. If the return value is true, the function will continue
// to execute when the GTK main loop is in this state.
go func() {
for {
time.Sleep(time.Second)
s := fmt.Sprintf("Set a label %d time(s)!", nSets)
_, err := glib.IdleAdd(LabelSetTextIdle, topLabel, s)
if err != nil {
log.Fatal("IdleAdd() failed:", err)
}
nSets++
s = fmt.Sprintf("Set a label %d time(s)!", nSets)
_, err = glib.IdleAdd(bottomLabel.SetText, s)
if err != nil {
log.Fatal("IdleAdd() failed:", err)
}
nSets++
}
}()
win.ShowAll()
gtk.Main()
}
// TestConnectNotifySignal ensures that property notification signals (those
// whose name begins with "notify::") are queried by the name "notify" (with the
// "::" and the property name omitted). This is because the signal is "notify"
// and the characters after the "::" are not recognized by the signal system.
//
// See
// https://developer.gnome.org/gobject/stable/gobject-The-Base-Object-Type.html#GObject-notify
// for background, and
// https://developer.gnome.org/gobject/stable/gobject-Signals.html#g-signal-new
// for the specification of valid signal names.
func TestConnectNotifySignal(t *testing.T) {
runtime.LockOSThread()
// Create any GObject that has defined properties.
spacing := 0
box, _ := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, spacing)
// Connect to a "notify::" signal to listen on property changes.
box.Connect("notify::spacing", func() {
gtk.MainQuit()
})
glib.IdleAdd(func(s string) bool {
t.Log(s)
spacing++
box.SetSpacing(spacing)
return true
}, "IdleAdd executed")
gtk.Main()
}