Changed 'Tabbable/Focusable' logic to use Active

wdgt_datepicker.go

@@ -131,12 +131,13 @@ func (w *DatePicker) Draw(screen tcell.Screen) {
 
 func (w *DatePicker) SetStyle(s tcell.Style) { w.style = s }
 func (w *DatePicker) Active() bool           { return w.active }
-func (w *DatePicker) SetActive(a bool) {
+func (w *DatePicker) SetActive(a bool) bool {
 	if !w.active && a {
 		// Wasn't active, but turning on
 		w.dateFld.SetActive(true)
 	}
 	w.active = a
+	return w.active
 }
 func (w *DatePicker) Visible() bool       { return w.visible }
 func (w *DatePicker) SetVisible(a bool)   { w.visible = a }