code: func (l *TableView) EnsureRowVisible() {
  	length := l.rowCount
  
  	hgt := l.height - 3
  
  	if length <= hgt || l.selectedRow == -1 {
  		return
  	}
  
  	diff := l.selectedRow - l.topRow
  	if diff >= 0 && diff < hgt {
  		return
  	}
  
  	if diff < 0 {
  		l.topRow = l.selectedRow
  	} else {
  		top := l.selectedRow - hgt + 1
  		if length-top > hgt {
  			l.topRow = top
  		} else {
  			l.topRow = length - hgt
  		}
  	}
  }
docs: // EnsureRowVisible scrolls the table vertically
  // to make the currently selected row visible