code: func (b *BoxLayout) Draw() {
  
  	if b.view == nil {
  		return
  	}
  	if b.changed {
  		b.layout()
  	}
  	b.view.Fill(' ', b.style)
  	for i := range b.cells {
  		b.cells[i].widget.Draw()
  	}
  }
docs: // Draw is called to update the displayed content.