Improvements to menus

Major progress on #4

menuitem.go

@@ -20,10 +20,15 @@ type MenuItem struct {
 
 // NewMenuItem creates a new menu item with the specified text.
 func NewMenuItem (text string) *MenuItem {
+	return NewIconMenuItem(tomo.IconUnknown, text)
+}
+
+// NewIconMenuItem creates a new menu item with the specified icon and text.
+func NewIconMenuItem (icon tomo.Icon, text string) *MenuItem {
 	box := &MenuItem {
 		ContainerBox: tomo.NewContainerBox(),
 		label:        NewLabel(text),
-		icon:         NewIcon("", tomo.IconSizeSmall),
+		icon:         NewIcon(icon, tomo.IconSizeSmall),
 	}
 	box.SetRole(tomo.R("objects", "MenuItem"))
 	box.label.SetAttr(tomo.AAlign(tomo.AlignStart, tomo.AlignMiddle))
@@ -49,8 +54,7 @@ func (this *MenuItem) SetText (text string) {
 // SetIcon sets an icon for this item. Setting the icon to IconUnknown will
 // remove it.
 func (this *MenuItem) SetIcon (id tomo.Icon) {
-	if this.icon != nil { this.Remove(this.icon) }
-	this.Insert(NewIcon(id, tomo.IconSizeSmall), this.label)
+	this.icon.SetIcon(id, tomo.IconSizeSmall)
 }
 
 // OnClick specifies a function to be called when the menu item is clicked.