adb：no devices/emulators found

使用adb，突然找不到设备了。。。no devices/emulators found

$ adb devices

List of devices attached

1.那么可以查找一下Android SDK的目录：

$ echo $PATH

/Users/admin/.rvm/gems/ruby-2.2.4/bin:/Users/admin/.rvm/gems/ruby-2.2.4@global/bin:/Users/admin/.rvm/rubies/ruby-2.2.4/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Java/JavaVirtualMachines/jdk1.7.0_79.jdk/Contents/Home:/Users/admin/Library/Android/sdk/platform-tools:/Users/admin/.rvm/bin

2.复制Home后面的地址：/Users/admin/Library/Android/sdk/platform-tools

3.设置genymotion的adb选项卡中的sdk路径：/Users/admin/Library/Android/sdk/