Correct me if I'm wrong but I found it quite hard to apply a
selected style to the selected stack panel header.
I came up with a workaround like this:
StackLayoutPanel danielStackPanel = new StackLayoutPanel
(Style.Unit.PX) {
@Override
public void showWidget(Widget widget) {
//
You're right, there is no notification to stack-header widgets of their
selection state. I'll make a note to add a standard way for them to be
notified of this.
As for standard CSS, with the current design (i.e., your own widget is the
only header element), there's nothing to add a default style
