Kotlin y Proguard

Después de haber convertido mi proyecto de Android a Kotlin, no puedo build una versión de lanzamiento, el error parece estar relacionado con Proguard.

Veo 155 advertencias como

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 

y la construcción falla con

 Error:Execution failed for task ':MyApp:transformClassesAndResourcesWithProguardForFreeRelease'. > Job failed, see logs for details 

Si cambio estas directivas en build.grade de verdadero a falso, la compilation tiene éxito.

 minifyEnabled true shrinkResources true 

¿Alguna sugerencia sobre cuál podría ser el problema?


Los files de proguard están a continuación:


 # 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.** 


 # 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.** 

La configuration de firma se define como se muestra a continuación

 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 } }