https://qooah.com/2011/10/26/%e5%8d%8a%e6%95%b8-android-%e7%94%a2%e5%93%81%e9%83%bd%e9%9c%80%e5%90%91-m-%e7%b9%b3%e5%b0%88%e5%88%a9%e8%b2%bb/