https://qooah.com/2012/09/17/%e6%90%ad%e8%bc%89-android-%e7%9a%84-hp-%e6%99%ba%e8%83%bd%e6%89%8b%e6%a9%9f%e7%8f%be%e8%ba%ab%e6%b8%ac%e8%a9%a6%e7%b6%b2%e7%ab%99/