1.找到你的debug.keystore文件
在Eclipse工具下，选择windows-->Preference-->Android-->Build,其中Default debug keystore的值便是debug.keystore的路径了。
2.获取 机器的MD5和SHA1的值
cmd cd sdk路径\tools
keytool -exportcert -alias androiddebugkey -keystore "debug.keystore的路径" -list -v -storepass android -keypass android
MD5:12:2E:CF:61:8B:9D:57:40:AA:3C:B0:1B:9D:E4:05:D7
SHA1:8C:11:E6:69:BE:3D:E1:0A:75:BF:64:64:23:0C:77:0A:FE:E9:EE:00
3:https://code.google.com/apis/console/#project:632988787097:access
services --> 选择 Google Maps Android API v2
API Access --> Create new Android key...--> 输入 8C:11:E6:69:BE:3D:E1:0A:75:BF:64:64:23:0C:77:0A:FE:E9:EE:00;com.example.mapdemo