After having converted my Android project to Kotlin I am unable to build a release build, the error appears to be related to Proguard.
I see 155 warnings like
Warning:com.example.app.activity.MainActivity$1: can't find referenced field 'android.view.View decorView' in program class com.example.app.activity.MainActivity
Warning:com.example.app.activity.MainActivity$2: can't find referenced field 'android.os.Handler handler' in program class com.example.app.activity.MainActivity
and the build fails with
Error:Execution failed for task ':MyApp:transformClassesAndResourcesWithProguardForFreeRelease'.
> Job failed, see logs for details
If I change these directives in build.grade from true to false the build succeeds.
minifyEnabled true
shrinkResources true
Any suggestions on what the issue might be?
Edit:
The proguard files are below:
proguard-android.txt
# This is a configuration file for ProGuard.
# http://proguard.sourceforge.net/index.html#manual/usage.html
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-verbose
# 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
# If you want to enable optimization, you should include the
# following:
# -optimizations !code/simplification/arithmetic,!code/simplification/cast,!field/*,!class/merging/*
# -optimizationpasses 5
# -allowaccessmodification
#
# Note that you cannot just include these flags in your own
# configuration file; if you are including this file, optimization
# will be turned off. You'll need to either edit this file, or
# duplicate the contents of this file and remove the include of this
# file from your project's proguard.config path property.
-keepattributes *Annotation*
-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider
-keep public class * extends android.app.backup.BackupAgent
-keep public class * extends android.preference.Preference
-keep public class * extends android.support.v4.app.Fragment
-keep public class * extends android.app.Fragment
-keep public class com.android.vending.licensing.ILicensingService
# For native methods, see http://proguard.sourceforge.net/manual/examples.html#native
-keepclasseswithmembernames class * {
native <methods>;
}
-keep public class * extends android.view.View {
public <init>(android.content.Context);
public <init>(android.content.Context, android.util.AttributeSet);
public <init>(android.content.Context, android.util.AttributeSet, int);
public void set*(...);
}
-keepclasseswithmembers class * {
public <init>(android.content.Context, android.util.AttributeSet);
}
-keepclasseswithmembers class * {
public <init>(android.content.Context, android.util.AttributeSet, int);
}
-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 <fields>;
}
# 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.**
-dontwarn io.codetail.animation.**
proguard-rules.txt
# Add project specific ProGuard rules here.
# By default, the flags in this file are appended to flags specified
# in /home/francesc/droids/android-sdk-linux/tools/proguard/proguard-android.txt
# You can edit the include path and order by changing the ProGuard
# include property in project.properties.
#
# For more details, see
# http://developer.android.com/guide/developing/tools/proguard.html
# Add any project specific keep options here:
# If your project uses WebView with JS, uncomment the following
# and specify the fully qualified class name to the JavaScript interface
# class:
#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
# public *;
#}
-keep class com.nineoldandroids.** { *; }
-dontwarn io.codetail.animation.**
The signing config is defined as shown below
signingConfigs {
myConfig {
Properties keyProps = new Properties()
keyProps.load(new FileInputStream(file('../release.properties')))
storeFile file(keyProps["store"])
keyAlias keyProps["alias"]
storePassword keyProps["storePass"]
keyPassword keyProps["keyPass"]
}
}
buildTypes {
release {
proguardFiles 'proguard-android.txt', 'proguard-rules.txt'
minifyEnabled true
shrinkResources true
signingConfig signingConfigs.myConfig
}
}
