如何在 Android Studio 中使用 ProGuard？

Try renaming your 'proguard-rules.txt' file to 'proguard-android.txt' and remove the reference to 'proguard-rules.txt' in your gradle file. The getDefaultProguardFile(...) call references a different default proguard file, one provided by Google and not that in your project. So remove this as well, so that here the gradle file reads:

buildTypes {
release {
runProguard true
proguardFile 'proguard-android.txt'
}
}

You can configure your build.gradle file for proguard implementation. It can be at module level or the project level.

 buildTypes {


debug {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'


}


}

The configuration shown is for debug level but you can write you own build flavors like shown below inside buildTypes:

    myproductionbuild{
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
}

Better to have your debug with minifyEnabled false and productionbuild and other builds as minifyEnabled true.

Copy your proguard-rules.txt file in the root of your module or project folder like

$YOUR_PROJECT_DIR\YoutProject\yourmodule\proguard-rules.txt

You can change the name of your file as you want. After configuration use one of the three options available to generate your build as per the buildType

1. Go to gradle task in right panel and search for assembleRelease/assemble(#your_defined_buildtype) under module tasks

2. Go to Build Variant in Left Panel and select the build from drop down

3. Go to project root directory in File Explorer and open cmd/terminal and run

Linux ./gradlew assembleRelease or assemble(#your_defined_buildtype)

Windows gradlew assembleRelease or assemble(#your_defined_buildtype)

You can find apk in your module/build directory.

More about the configuration and proguard files location is available at the link

http://tools.android.com/tech-docs/new-build-system/user-guide#TOC-Running-ProGuard

You're probably not actually signing the release build of the APK via the signing wizard. You can either build the release APK from the command line with the command:

./gradlew assembleRelease

or you can choose the release variant from the Build Variants view and build it from the GUI:

NB.: Now instead of

runProguard false

you'll need to use

minifyEnabled false

The other answers here are great references on using proguard. However, I haven't seen an issue discussed that I ran into that was a mind bender. After you generate a signed release .apk, it's put in the /release folder in your app but my app had an apk that wasn't in the /release folder. Hence, I spent hours decompiling the wrong apk wondering why my proguard changes were having no affect. Hope this helps someone!

Here is Some of Most Common Proguard Rules that you need to add in proguard-rules.pro file in Android Sutdio.

ButterKnife

 -keep class butterknife.** { *; }
-dontwarn butterknife.internal.**
-keep class **$$ViewBinder { *; }
-keepclasseswithmembernames class * {
@butterknife.* <fields>;
}
-keepclasseswithmembernames class * {
@butterknife.* <methods>;
}

Retrofit

 -dontwarn retrofit.**
-keep class retrofit.** { *; }
-keepattributes Signature
-keepattributes Exceptions

OkHttp3

 -keepattributes Signature
-keepattributes *Annotation*
-keep class okhttp3.** { *; }
-keep interface okhttp3.** { *; }
-dontwarn okhttp3.**
-keep class sun.misc.Unsafe { *; }
-dontwarn java.nio.file.*
-dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement

Gson

 -keep class sun.misc.Unsafe { *; }
-keep class com.google.gson.stream.** { *; }

Code obfuscation

-keepclassmembers class com.yourname.models** { <fields>; }

Enable ProGuard

[ProGuard flow]

android {
buildTypes {
release {
minifyEnabled true
proguardFiles 'proguard-rules.pro'
}
}
}

[ProGuard artefact]