android 中apk如何防止反编译？

android 2.3以上：

很简单的一句话"在default.properties文件最后添加proguard.config=proguard.cfg" 

android2.3及以下：

复制下面default.properties文件到你的工程目录即可,注意target的版本号：

 # This file is automatically generated by Android Tools.
 # Do not modify this file -- YOUR CHANGES WILL BE ERASED!
 #
 # This file must be checked in Version Control Systems.
 #
 # To customize properties used by the Ant build system use,
 # "build.properties", and override values to adapt the script to your
 # project structure.

 # Project target.
 target=android-9
 proguard.config=proguard.cfg