code: func (ww *WidgetWatchers) PostEventWidgetResize(w Widget) {
  	ev := &EventWidgetResize{}
  	ev.SetWidget(w)
  	ev.SetEventNow()
  	ww.PostEvent(ev)
  }
docs: // PostEventWidgetResize is called by the Widget when the underlying View
  // has resized, delivering EventWidgetResize to all watchers.