留作记录： 12 Platform Version API Level VERSION_CODE Notes Android 5.1 22 LOLLIPOP_MR1 Platform Highlights Android 5.0 21 LOLLIPOP Android 4.4W 20 KITKAT_WATCH KitKat for Wearables Only Android 4.4 19 KITKAT Platform Highlights Android 4.3 18 JELLY_BEAN_MR2 Platform Highlights Android 4.2, 4.2.2 17 JELLY_BEAN_MR1 Platform Highlights 修改了SecureRandom，伪随机变化 Android 4.1, 4.1.1 16 JELLY_BEAN Platform Highl ...