java.lang.ExceptionInInitializerError when running flutter release mode

My flutter app works fine in debug mode. But, when I run it with flutter run --release I am getting the following error.

E/AndroidRuntime(18551):    java.lang.ExceptionInInitializerError
E/AndroidRuntime(18551):    at e.c.M1.o.forTarget(Unknown Source:0)
E/AndroidRuntime(18551):    at e.c.M1.p.a(:1)
E/AndroidRuntime(18551):    at e.c.J0.b(:2)
E/AndroidRuntime(18551):    at com.google.firebase.firestore.p0.V.e(:2)
E/AndroidRuntime(18551):    at com.google.firebase.firestore.p0.r.call(Unknown Source:2)
E/AndroidRuntime(18551):    at c.d.a.b.l.O.run(Unknown Source:4)
E/AndroidRuntime(18551):    at com.google.firebase.firestore.q0.G.a(:1)
E/AndroidRuntime(18551):    at com.google.firebase.firestore.q0.l.run(Unknown Source:4)
E/AndroidRuntime(18551):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
E/AndroidRuntime(18551):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
E/AndroidRuntime(18551):    at java.lang.Thread.run(Thread.java:923)
E/AndroidRuntime(18551): Caused by: java.lang.RuntimeException: java.lang.NoSuchMethodException: e.c.J1.values []
E/AndroidRuntime(18551):    at java.lang.Enum.enumValues(Enum.java:270)
E/AndroidRuntime(18551):    at java.lang.Enum.access$000(Enum.java:61)
E/AndroidRuntime(18551):    at java.lang.Enum$1.create(Enum.java:277)
E/AndroidRuntime(18551):    at java.lang.Enum$1.create(Enum.java:275)
E/AndroidRuntime(18551):    at libcore.util.BasicLruCache.get(BasicLruCache.java:63)
E/AndroidRuntime(18551):    at java.lang.Enum.getSharedConstants(Enum.java:289)
E/AndroidRuntime(18551):    at java.lang.Class.getEnumConstantsShared(Class.java:2428)
E/AndroidRuntime(18551):    at java.util.EnumSet.getUniverse(EnumSet.java:407)
E/AndroidRuntime(18551):    at java.util.EnumSet.noneOf(EnumSet.java:109)
E/AndroidRuntime(18551):    at java.util.EnumSet.of(EnumSet.java:235)
E/AndroidRuntime(18551):    at e.c.M1.o.<clinit>(Unknown Source:100)
E/AndroidRuntime(18551):    ... 11 more
E/AndroidRuntime(18551): Caused by: java.lang.NoSuchMethodException: e.c.J1.values []
E/AndroidRuntime(18551):    at java.lang.Class.getMethod(Class.java:2072)
E/AndroidRuntime(18551):    at java.lang.Class.getDeclaredMethod(Class.java:2050)
E/AndroidRuntime(18551):    at java.lang.Enum.enumValues(Enum.java:267)
E/AndroidRuntime(18551):    ... 21 more

I’ve tried some ways like upgrading gradle, upgrading some dependencies to latest versions. But still it’s not solved. Can you give any ideas on how to solve this?

Answer

I am using flutter and , I have found solution.

There are some steps , you must do, please follow correctly:

STEP 1:

In /Android/app folder:

find below files: proguard-android.txt proguard-rules.pro

if they are not exists create them, with same name.

STEP 2:

Paste this code into both files (proguard-android.txt and proguard-rules.pro):

   -keep class io.grpc.** {*;}
   -keepclassmembers enum * {
    public static **[] values();
    public static ** valueOf(java.lang.String);
}

STEP 3:

in /Android/app/build.gradle make sure that, theese lines have added:

 buildTypes {
    release {
        // TODO: Add your own signing config for the release build.
        // Signing with the debug keys for now, so `flutter run --release` works.
        signingConfig signingConfigs.release //If in debug, change release to debug

        minifyEnabled true
        useProguard true
        shrinkResources true

        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' *//I add this line...*
    } }

STEP 4:

in terminal of Android Studio

flutter clean

then

flutter pub get

after theese steps it must work.