private <T extends Widget> T add0(T child) {
if (this.ui != null) ((Widget) child).attach(this.ui);
child.parent = this;
child.link();
child.added();
if (((Widget) child).canfocus && child.visible) newfocusable(child);
return (child);
}
protected void attach(UI ui) {
this.ui = ui;
for (Widget ch = child; ch != null; ch = ch.next) ch.attach(ui);
}