code: func (p *Pages) ShowPage(name string) *Pages {
  	for _, page := range p.pages {
  		if page.Name == name {
  			page.Visible = true
  			if p.changed != nil {
  				p.changed()
  			}
  			break
  		}
  	}
  	if p.HasFocus() {
  		p.Focus(p.setFocus)
  	}
  	return p
  }
docs: // ShowPage sets a page's visibility to "true" (in addition to any other pages
  // which are already visible).