Added extended selection capabilities to the API

backends/x/window.go

@@ -78,7 +78,7 @@ func (backend *Backend) NewWindow (
 func (window *Window) Adopt (child tomo.Element) {
 	if window.child != nil {
 		child.SetParentHooks (tomo.ParentHooks { })
-		if child.Selectable() { child.Handle(tomo.EventDeselect { }) }
+		if child.Selected() { child.Handle(tomo.EventDeselect { }) }
 	}
 	window.child = child
 	if child != nil {
@@ -87,12 +87,7 @@ func (window *Window) Adopt (child tomo.Element) {
 			MinimumSizeChange: window.childMinimumSizeChangeCallback,
 			SelectionRequest: window.childSelectionRequestCallback,
 		})
-		// TODO: it is possible for an element to start out as
-		// selectable, and then become unselectable. it should be
-		// standard behavior for containers (including windows) to, if
-		// no children are selected, select the first child on ctrl-tab
-		// press. we should therefore be able to ask any element if it
-		// is selected.
+		
 		if child.Selectable() { child.Handle(tomo.EventSelect { }) }
 		window.resizeChildToFit()
 	}