HarmonyOS 如何获取屏幕顶部和底部安全区域的高度

onPageShow(): void { window.getLastWindow(getContext(this), (err, win) => { 
  //获取避让类型为系统导航条 
  let type = window.AvoidAreaType.TYPE_NAVIGATION_INDICATOR; 
  let avoidArea = win.getWindowAvoidArea(type); 
  let bottomRectHeight = px2vp(avoidArea.bottomRect.height); 
  let topRectRectHeight = px2vp(avoidArea.topRect.height); 
 
  console.log("bottomRectHeight :::: " + bottomRectHeight); 
  console.log("topRectRectHeight :::: " + topRectRectHeight); 
}) 
}