Added Checkbox.SetChecked() and implemented it on GTK+.

checkbox.go

@@ -12,7 +12,7 @@ type Checkbox struct {
 	created   bool
 	sysData   *sysData
 	initText  string
-	initCheck bool
+	initCheck		bool
 }
 
 // NewCheckbox creates a new checkbox with the specified text.
@@ -46,7 +46,19 @@ func (c *Checkbox) Text() string {
 	return c.initText
 }
 
-// Checked() returns whether or not the checkbox has been checked.
+// SetChecked() changes the checked state of the Checkbox.
+func (c *Checkbox) SetChecked(checked bool) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	if c.created {
+		c.sysData.setChecked(checked)
+		return
+	}
+	c.initCheck = checked
+}
+
+// Checked() returns whether or not the Checkbox has been checked.
 func (c *Checkbox) Checked() bool {
 	c.lock.Lock()
 	defer c.lock.Unlock()
@@ -54,7 +66,7 @@ func (c *Checkbox) Checked() bool {
 	if c.created {
 		return c.sysData.isChecked()
 	}
-	return false
+	return c.initCheck
 }
 
 func (c *Checkbox) make(window *sysData) error {
@@ -66,6 +78,7 @@ func (c *Checkbox) make(window *sysData) error {
 		return err
 	}
 	c.sysData.setText(c.initText)
+	c.sysData.setChecked(c.initCheck)
 	c.created = true
 	return nil
 }

gtkcalls_unix.go

@@ -153,6 +153,10 @@ func gtk_toggle_button_get_active(widget *C.GtkWidget) bool {
 	return fromgbool(C.gtk_toggle_button_get_active(togtktogglebutton(widget)))
 }
 
+func gtk_toggle_button_set_active(widget *C.GtkWidget, checked bool) {
+	C.gtk_toggle_button_set_active(togtktogglebutton(widget), togbool(checked))
+}
+
 func gtk_combo_box_text_new() *C.GtkWidget {
 	w := C.gtk_combo_box_text_new()
 	C.gtkSetComboBoxArbitrarilyResizeable(w)

sysdata.go

@@ -41,6 +41,7 @@ var _xSysData interface {
 	setAreaSize(int, int)
 	repaintAll()
 	center()
+	setChecked(bool)
 } = &sysData{} // this line will error if there's an inconsistency
 
 // signal sends the event signal. This raise is done asynchronously to avoid deadlocking the UI task.

sysdata_unix.go

@@ -410,3 +410,13 @@ func (s *sysData) center() {
 	}
 	<-ret
 }
+
+func (s *sysData) setChecked(checked bool) {
+	ret := make(chan struct{})
+	defer close(ret)
+	uitask <- func() {
+		gtk_toggle_button_set_active(s.widget, checked)
+		ret <- struct{}{}
+	}
+	<-ret
+}

test/main.go

@@ -34,6 +34,7 @@ func gridWindow() *Window {
 	b12 := NewButton("1,2")
 	l20 := NewLabel("2,0")
 	c21 := NewCheckbox("2,1")
+	c21.SetChecked(true)
 	l22 := NewLabel("2,2")
 	g := NewGrid(3,
 		b00, b01, b02,
@@ -43,6 +44,10 @@ func gridWindow() *Window {
 	g.SetStretchy(1, 1)
 	w.SetSpaced(*spacingTest)
 	w.Open(g)
+	go func() {for {select {
+	case <-b12.Clicked:
+		c21.SetChecked(!c21.Checked())
+	}}}()
 	return w
 }