Removed the initText parameter from sysData.make() and changed all invocations to call sysData.setText() separately; this avoids the need to check if sysData.setText() is valid. Also implemented that on GTK+.

area.go

@@ -288,7 +288,7 @@ func (a *Area) make(window *sysData) error {
 	defer a.lock.Unlock()
 
 	a.sysData.handler = a.handler
-	err := a.sysData.make("", window)
+	err := a.sysData.make(window)
 	if err != nil {
 		return err
 	}

button.go

@@ -55,10 +55,11 @@ func (b *Button) make(window *sysData) error {
 	defer b.lock.Unlock()
 
 	b.sysData.event = b.Clicked
-	err := b.sysData.make(b.initText, window)
+	err := b.sysData.make(window)
 	if err != nil {
 		return err
 	}
+	b.sysData.setText(b.initText)
 	b.created = true
 	return nil
 }

checkbox.go

@@ -63,10 +63,11 @@ func (c *Checkbox) make(window *sysData) error {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
-	err := c.sysData.make(c.initText, window)
+	err := c.sysData.make(window)
 	if err != nil {
 		return err
 	}
+	c.sysData.setText(c.initText)
 	c.created = true
 	return nil
 }

combobox.go

@@ -138,7 +138,7 @@ func (c *Combobox) make(window *sysData) (err error) {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
-	err = c.sysData.make("", window)
+	err = c.sysData.make(window)
 	if err != nil {
 		return err
 	}

label.go

@@ -49,10 +49,11 @@ func (l *Label) make(window *sysData) error {
 	l.lock.Lock()
 	defer l.lock.Unlock()
 
-	err := l.sysData.make(l.initText, window)
+	err := l.sysData.make(window)
 	if err != nil {
 		return err
 	}
+	l.sysData.setText(l.initText)
 	l.created = true
 	return nil
 }

lineedit.go

@@ -61,10 +61,11 @@ func (l *LineEdit) make(window *sysData) error {
 	defer l.lock.Unlock()
 
 	l.sysData.alternate = l.password
-	err := l.sysData.make(l.initText, window)
+	err := l.sysData.make(window)
 	if err != nil {
 		return err
 	}
+	l.sysData.setText(l.initText)
 	l.created = true
 	return nil
 }

listbox.go

@@ -139,7 +139,7 @@ func (l *Listbox) make(window *sysData) (err error) {
 	l.lock.Lock()
 	defer l.lock.Unlock()
 
-	err = l.sysData.make("", window)
+	err = l.sysData.make(window)
 	if err != nil {
 		return err
 	}

progressbar.go

@@ -47,7 +47,7 @@ func (p *ProgressBar) make(window *sysData) error {
 	p.lock.Lock()
 	defer p.lock.Unlock()
 
-	err := p.sysData.make("", window)
+	err := p.sysData.make(window)
 	if err != nil {
 		return err
 	}

sysdata.go

@@ -21,7 +21,7 @@ type cSysData struct {
 
 // this interface is used to make sure all sysDatas are synced
 var _xSysData interface {
-	make(initText string, window *sysData) error
+	make(window *sysData) error
 	firstShow() error
 	show()
 	hide()

sysdata_unix.go

@@ -64,7 +64,6 @@ var classTypes = [nctypes]*classData{
 	c_combobox:		&classData{
 		make:		gtk_combo_box_text_new,
 		makeAlt:		gtk_combo_box_text_new_with_entry,
-		// TODO setText
 		text:			gtk_combo_box_text_get_active_text,
 		append:		gtk_combo_box_text_append_text,
 		insert:		gtk_combo_box_text_insert_text,
@@ -86,7 +85,6 @@ var classTypes = [nctypes]*classData{
 	c_listbox:			&classData{
 		make:		gListboxNewSingle,
 		makeAlt:		gListboxNewMulti,
-		// TODO setText
 		text:			gListboxText,
 		append:		gListboxAppend,
 		insert:		gListboxInsert,
@@ -112,7 +110,7 @@ var classTypes = [nctypes]*classData{
 	},
 }
 
-func (s *sysData) make(initText string, window *sysData) error {
+func (s *sysData) make(window *sysData) error {
 	ct := classTypes[s.ctype]
 	ret := make(chan *C.GtkWidget)
 	defer close(ret)
@@ -152,7 +150,6 @@ func (s *sysData) make(initText string, window *sysData) error {
 		}
 		<-ret
 	}
-	s.setText(initText)
 	return nil
 }
 
@@ -183,9 +180,6 @@ func (s *sysData) hide() {
 }
 
 func (s *sysData) setText(text string) {
-	if classTypes[s.ctype].setText == nil {		// does not have concept of text
-		return
-	}
 	ret := make(chan struct{})
 	defer close(ret)
 	uitask <- func() {

window.go

@@ -72,7 +72,7 @@ func (w *Window) Open(control Control) (err error) {
 		panic("window already open")
 	}
 	w.sysData.event = w.Closing
-	err = w.sysData.make(w.initTitle, nil)
+	err = w.sysData.make(nil)
 	if err != nil {
 		return fmt.Errorf("error opening window: %v", err)
 	}
@@ -87,6 +87,7 @@ func (w *Window) Open(control Control) (err error) {
 	if err != nil {
 		return fmt.Errorf("error setting window size (in Window.Open()): %v", err)
 	}
+	w.sysData.setText(w.initTitle)
 	// TODO separate showing?
 	err = w.sysData.firstShow()
 	if err != nil {