Please add the output of flutter doctor -v.

What do the contents of the APK zip file look like before and after adding the fabric.io dependency?

The assertion failure indicates that the Flutter engine can not find the assets representing the application's Dart code.

Look for files in the APK such as assets/flutter_assets/isolate_snapshot_data, assets/flutter_assets/kernel_blob.bin, assets/flutter_assets/platform.dill, and assets/flutter_assets/vm_snapshot_data.

Are these files still present in the right places after adding fabric.io?

this is flutter doctor,everything is fine

@jason-simmons
APK after add fabric have assets flutter such as isolate_snapshot_data,vm_snapshot_data.But when i add fabric,it gone!!!

Hi i found reason make app crash.
apply plugin: 'io.fabric'
This is a code make crash app,when i remove it app working.But when i remove that code,i can't install fabric in my app!!!

I was also so. Is there a way to fix it?

I also had the exactly same problem, can confirm that removing the apply plugin from fabric solves the problem, but is there a way to keep using fabric? Is it a problem with the fabric plugin itself?

I had the problem too.Is there some way to solve this problem without remove fabric ?

Here ! I fixed this. You can checkout Upgrading Flutter channel master "https://flutter.io/upgrading/" . You without remove fabric. When you upgrading after restart your project.

Still not work .

add this line in strings.xml
"< string name="com.crashlytics.RequireBuildId">false < /string > "
and remove : apply plugin: 'io.fabric'
in build.gradle
Now fabric still work and when you build release flutter not crash.I don't know why,but it woking.You can try

@haihai111 thanks you. I can do it. But i don't know why?. I think Fultter add plugin faric ✌️

when the app crash , I find that apk's assets path missing "flutter_shared" .

@mravn did you happen to root cause the Gradle issue here?

@matthew-carroll Sorry, no.

I do not have apply plugin: 'io.fabric' in my gradle but still get this error

after one day research, finally I find this

Go to you_flutter_project/.android
run ./gradlew assembleDebug and generate flutter-debug.aar it contains flutter_assets folder

but

run ./gradlew flutter:assembleDebug does not contains flutter_assets folder

hi, all, In my situation, I pulled my flutter module from git repository.
I run flutter clean and flutter run then everything is ok

hi, all, In my situation, I pulled my flutter module from git repository.
I run flutter clean and flutter run then everything is ok

you can just run gradlew assembleDebug or gradlew assembleRelease

@kimlet is right. The main reason for E/flutter: [ERROR:flutter/runtime/dart_vm.cc(259)] VM snapshot must be valid. is missing of flutter_assets. For my case, I temporarily get around this matter by doing folowing steps (I use MacOS):

1. run ./gradlew assemble inside .android.
2. go to .android/Flutter/build/outputs/aar/, copy a proper aar file (there're some aar file for debug, release and profile), extract it with unzip command and copy flutter_asssets in extracted folder.
3. create assets folder inside my existing Android project, paste fluter_assets there. Done!

The reason of why flutter doesn't pack flutter_assets to output apk file in my case is still unexplained. It's even more curious when I create a new dummy android project and try to add flutter module to it. It works well. I guess that my real project has some problems in gradle config that causes flutter ignoring flutter_assets

@hnvn exactly the same problem here, I have tried your steps, still gone crash, so sad~

@kimlet is right. The main reason for E/flutter: [ERROR:flutter/runtime/dart_vm.cc(259)] VM snapshot must be valid. is missing of flutter_assets. For my case, I temporarily get around this matter by doing folowing steps (I use MacOS):

1. run ./gradlew assemble inside .android.
2. go to .android/Flutter/build/outputs/aar/, copy a proper aar file (there're some aar file for debug, release and profile), extract it with unzip command and copy flutter_asssets in extracted folder.
3. create assets folder inside my existing Android project, paste fluter_assets there. Done!

The reason of why flutter doesn't pack flutter_assets to output apk file in my case is still unexplained. It's even more curious when I create a new dummy android project and try to add flutter module to it. It works well. I guess that my real project has some problems in gradle config that causes flutter ignoring flutter_assets

Thank you! It does work for me!

@hnvn
I tried your steps and they worked for me as well.

I have have question though:
Have you copied your android project into the path <<../my_flutter/> after you created the flutter module? (flutter create -t module my_flutter)
I am asking this because this is one of the more important changes I had done to my setup before I broke the build.
Anyway, thanks a lot for your steps!

I find the reason:
if you config Flavor in app, the flutter lib must config the same Flavor.
if not, such as compileDevDebug will not found when build.

so, add the app's Flavor to the Flutter lib module, make the lib has the same compileDevDebug.

I find the reason:
if you config Flavor in app, the flutter lib must config the same Flavor.
if not, such as compileDevDebug will not found when build.

so, add the app's Flavor to the Flutter lib module, make the lib has the same compileDevDebug.
it works！

@yk3372 thank you so much for this piece of advice. It helped me fix the error and run my Flutter module successfully. For other users experiencing this problem, you have to add the flavors you have in your app to the Flutter plugin's build.grade. It is not necessary to add flavors to the generated .android build.gradle file.
The flavors should only contain the flavor names and not any configurations in order to not conflict with your app's flavor settings.

Example:

    buildTypes {
        release {
        }

        debug {
        }
    }
    flavorDimensions "environment"
    productFlavors {
        dev {
        }
        qa {
        }
        prod {
        }
    }

I can confirm that adding empty build types and flavours fixes problem with integrating flutter module into existing application ❤️

I find the reason:
if you config Flavor in app, the flutter lib must config the same Flavor.
if not, such as compileDevDebug will not found when build.

so, add the app's Flavor to the Flutter lib module, make the lib has the same compileDevDebug.

it helps me thanks a lot

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.