一、修改工程下的project.properties文件如下：

# 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 edit
# "ant.properties", and override values to adapt the script to your
# project structure.
#
# To enable ProGuard to shrink and obfuscate your code, uncomment this (available properties: sdk.dir, user.home):
#proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt

# Project target.
target=android-10
proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt

其中最后一行为自行添加的 混淆脚本路径，具体脚本编写在 proguard-project.txt 脚本文件内进行。

二、修改脚本文件

为什么说事修改呢？ 很简单因为Google已经替我们完成了大部分功能，只需按自己需要增加规则就OK，我得 proguard-project.txt 文件如下：

# This is a configuration file for ProGuard.
# http://proguard.sourceforge.net/index.html#manual/usage.html

-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-verbose
# ignorewarnings
-ignorewarnings

# Optimization is turned off by default. Dex does not like code run
# through the ProGuard optimize and preverify steps (and performs some
# of these optimizations on its own).
-dontoptimize
-dontpreverify
# Note that if you want to enable optimization, you cannot just
# include optimization flags in your own project configuration file;
# instead you will need to point to the
# "proguard-android-optimize.txt" file instead of this one from your
# project.properties file.

-keepattributes *Annotation*
-keep public class com.google.vending.licensing.ILicensingService
-keep public class com.android.vending.licensing.ILicensingService

# For native methods, see http://proguard.sourceforge.net/manual/examples.html#native
-keepclasseswithmembernames class * {
native ;
}

# keep setters in Views so that animations can still work.
# see http://proguard.sourceforge.net/manual/examples.html#beans
-keepclassmembers public class * extends android.view.View {
void set*(***);
*** get*();
}

# We want to keep methods in Activity that could be used in the XML attribute onClick
-keepclassmembers class * extends android.app.Activity {
public void *(android.view.View);
}

# For enumeration classes, see http://proguard.sourceforge.net/manual/examples.html#enumerations
-keepclassmembers enum * {
public static **[] values();
public static ** valueOf(java.lang.String);
}

-keep class * implements android.os.Parcelable {
public static final android.os.Parcelable$Creator *;
}

-keepclassmembers class **.R$* {
public static ;
}

# The support library contains references to newer platform versions.
# Don't warn about those in case this app is linking against an older
# platform version. We know about them, and they are safe.
-dontwarn android.support.**

# -keep class android.support.v4.**{*;}
-keep class org.phprpc.**{*;}
-keep class com.google.gson.**{*;}

-keep class com.baidu.**{*;}
-keep class com.novell.sasl.client.**{*;}

-keep class org.**{*;}
-keep class com.hp.hpl.**{*;}

-keep class net.sourceforge.**{*;}

-keep class pinyindb.**{*;}
-keep class demo.**{*;}

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