Develop Reference

Android builds twice when using flutter flavours

I recently upgraded Flutter from 2.2.x to 2.10.x.
All was working fine on 2.2.x. On the new version, iOS works properly, but Android is having issues, as it seems to be running the app build.gradle twice: a first time with the proper flavour, a second time with no flavour.
The command is flutter run --flavor dev
The error I get is:
Launching lib/main.dart on sdk gphone x86 arm in debug mode...
lib/main.dart:1
Reading env from: .env.dev
Starting a Gradle Daemon, 1 busy and 8 stopped Daemons could not be reused, use --status for details
> Configure project :app
Reading env from: .env
**************************
*** Missing .env file ****
**************************
Deprecated Gradle features were used in this build, making it incompatible with Gradle 6.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/5.6.2/userguide/command_line_interface.html#sec:command_line_warnings
FAILURE: Build failed with an exception.
* Where:
Build file '/Users/guillaumeferron/Sites/TendoPay-App/android/app/build.gradle' line: 26
* What went wrong:
A problem occurred evaluating project ':app'.
> Cannot invoke method split() on null object
As you can see, there is a double "Reading env from", which should not happen. The first run works fine and goes through, but gets killed by the second run that fails.
The faulty line (which is not the issue itself, but a consequence of the dual run) is:
def flutterVersionCode = Double.parseDouble(project.env.get("APP_VERSION_ANDROID").split("\\.")[0]) * 10000 + Double.parseDouble(project.env.get("APP_VERSION_ANDROID").split("\\.")[1]) * 100 + Double.parseDouble(project.env.get("APP_VERSION_ANDROID").split("\\.")[2])
My flutter doctor is:
[✓] Flutter (Channel stable, 2.10.3, on macOS 12.2.1 21D62 darwin-x64, locale en-CA)
• Flutter version 2.10.3 at /Users/guillaumeferron/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 7e9793dee1 (3 weeks ago), 2022-03-02 11:23:12 -0600
• Engine revision bd539267b4
• Dart version 2.16.1
• DevTools version 2.9.2
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
• Android SDK at /Users/guillaumeferron/Library/Android/sdk
• Platform android-31, build-tools 30.0.2
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
• All Android licenses accepted.
[✓] Xcode - develop for iOS and macOS (Xcode 13.3)
• Xcode at /Applications/Xcode.app/Contents/Developer
• CocoaPods version 1.11.3
[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
[✓] Android Studio (version 4.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
[✓] IntelliJ IDEA Ultimate Edition (version 2021.2.2)
• IntelliJ at /Applications/IntelliJ IDEA.app
• Flutter plugin version 60.1.4
• Dart plugin version 212.5284.31
[✓] VS Code (version 1.65.2)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.36.0
[✓] Connected device (2 available)
• sdk gphone x86 arm (mobile) • emulator-5554 • android-x86 • Android 11 (API 30) (emulator)
• Chrome (web) • chrome • web-javascript • Google Chrome 99.0.4844.51
[✓] HTTP Host Availability
• All required HTTP hosts are available
• No issues found!
I've been looking around for a couple hours now, to no avail.
Flutter 2.10.x is not the problem itself, it is Android SDK 31 that is. Indeed, this only happens when I change the SDK version, unfortunately it is a required change in order to support the pub packages versions for 2.10.x.
If I println the different env variables I would get when having it as APP_VERSION_ANDROID="0.2.3" for instance, would be the first occurrence "0.2.3", and null the second, which triggers the error.
I have done all the flutter clean, flutter pub get, flutter pub upgrade, gradle clean, etc..
Any help would be appreciated, as I did not find anything relevant online, and lack the Android dev expertise to debug it myself.
Note: the flavour infrastructure I went for is https://medium.com/#animeshjain/build-flavors-in-flutter-android-and-ios-with-different-firebase-projects-per-flavor-27c5c5dac10b

For anyone stumbling upon this, after many hours of testing and research, what fixed it was to properly upgrade the Android version. So make sure that:
You open the project with Android Studio, and have all proper grade versions downloaded by going to File > Project Structure. Gradle should be v6.1.1 and Plugin v4.0.1
Set your kotlin version to v1.5.31 (https://docs.flutter.dev/release/breaking-changes/kotlin-version)
Have both your target and compile sdk version to 31
This should then work properly, and the gradle won't be executed a second time with no flavor.

Exception: Unsupported Android Plugin version: 4.2.1. when flutter run --release

I am using the latest flutter stable version , flutter doctor -v as below:
[✓] Flutter (Channel stable, 2.2.2, on Mac OS X 10.15.7 19H2 darwin-x64, locale en-IN)
• Flutter version 2.2.2 at /Users/daydreamers/Documents/development/flutter
• Framework revision d79295af24 (2 weeks ago), 2021-06-11 08:56:01 -0700
• Engine revision 91c9fc8fe0
• Dart version 2.13.3
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
• Android SDK at /Users/daydreamers/Library/Android/sdk
• Platform android-30, build-tools 30.0.2
• ANDROID_HOME = /Users/daydreamers/Library/Android/sdk
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6916264)
• All Android licenses accepted.
[✓] Xcode - develop for iOS and macOS
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 12.3, Build version 12C33
• CocoaPods version 1.10.1
[✗] Chrome - develop for the web (Cannot find Chrome executable at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome)
! Cannot find Chrome. Try setting CHROME_EXECUTABLE to a Chrome executable.
[✓] Android Studio (version 4.2)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6916264)
[✓] VS Code (version 1.57.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.23.0
[✓] Connected device (1 available)
I am having Kotlin code for Android and Kotlin version is
ext.kotlin_version = '1.5.20'
I have this in my dependencies :
classpath 'com.android.tools.build:gradle:4.2.1'
I get an error when running flutter run --release, but flutter run works fine.
Exception: Unsupported Android Plugin version: 4.2.1.
I have tried other Answers from SO like updating the JVM version for Kotlin target VM (I set it to 11 from 8) .
I also have distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-all.zip in gradle-wrapper.properties.
Any help is greatly appreciated.

See whether there is something like below in your app build.gradle (app/src/build.gradle)
productFlavors {
app_dev {
dimension "version"
applicationIdSuffix ".dev"
}
app_stg {
signingConfig signingConfigs.debug
dimension "version"
applicationIdSuffix ".stg"
}
app_prod {
signingConfig signingConfigs.release
dimension "version"
}
}
If it does have something like that, then you need to go to
Run -> Edit Configuration -> Pick your main.dart on left side -> Inside 'Build flavor' put "app_dev" inside the textbox (The string can be anything and it depends on what's inside your productFlavors { ... })
This helped me solve my issue.

I had a similar problem when building with flutter build apk --flavor my_flavor.
I had configured ABI splits in my app build.gradle, and removing them solved the issue since they weren't necessary in my case.

Flutter retuns error compiling hello world app

I am trying to run the "hello world" app that is generated when you create a new app. This is error that I keep getting when I try to run it in Visual Studio Code:
* What went wrong:
A problem was found with the configuration of task ':app:processDebugManifest' (type 'ProcessMultiApkApplicationManifest').
> File 'G:\Projects\flutter\brew_crew4\build\app\intermediates\merged_manifest\debug\out\AndroidManifest.xml' specified for property 'mainMergedManifest' does not exist.
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 3m 39s
Exception: Gradle task assembleDebug failed with exit code 1
I'm using JDK 1.8.291 and Gradle 7.0
I'm running the latest verion of Flutter as of the date of this post (2.2.3). Here is the output of "flutter doctor". There are no issues whatosever! On my Mac that has the saem version of Gradle and JDK, I can run flutter apps without problems!
• Flutter version 2.2.3 at d:\WebProjects\utils\flutter
• Framework revision f4abaa0735 (7 days ago), 2021-07-01 12:46:11 -0700
• Engine revision 241c87ad80
• Dart version 2.13.4
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
• Android SDK at D:\Android\Sdk
• Platform android-30, build-tools 30.0.3
• ANDROID_HOME = D:\Android\Sdk
• Java binary at: D:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6842174)
• All Android licenses accepted.
[✓] Chrome - develop for the web
• Chrome at C:\Program Files (x86)\Google\Chrome\Application\chrome.exe
[✓] Visual Studio - develop for Windows (Visual Studio Community 2019 16.9.4)
• Visual Studio at g:\Program Files (x86)\Microsoft Visual Studio\2019\Community
• Visual Studio Community 2019 version 16.9.31205.134
• Windows 10 SDK version 10.0.19041.0
[✓] Android Studio
• Android Studio at D:\Program Files\Android\Android Studio
• Flutter plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/6351-dart
• android-studio-dir = D:\Program Files\Android\Android Studio
• Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6842174)
[✓] VS Code (version 1.57.1)
• VS Code at C:\Users\User\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.24.0
[✓] Connected device (4 available)
• Android SDK built for x86 64 (mobile) • emulator-5554 • android-x64 • Android 10 (API 29) (emulator)
• Windows (desktop) • windows • windows-x64 • Microsoft Windows [Version
10.0.19043.1052]
• Chrome (web) • chrome • web-javascript • Google Chrome 91.0.4472.124
• Edge (web) • edge • web-javascript • Microsoft Edge 91.0.864.64
• No issues found!
I have tried reinstalling the JDK and Android Studio twice.
UPDATE: This is the contents of my build.gradle file:
ext.kotlin_version = '1.3.50'
repositories {
google()
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:4.1.0'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
}
allprojects {
repositories {
google()
jcenter()
}
}
rootProject.buildDir = '../build'
subprojects {
project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
project.evaluationDependsOn(':app')
}
task clean(type: Delete) {
delete rootProject.buildDir
}
Any help greatly appreciated!

SOLVED: Apparently, starting from Gradle 6.5, it stopped working well on drives formatted as exFAT. If you must have your project on an exFAT partitioned drive, downgrade the gradle plugin in build.gradle to 4.0.2:
dependencies {
classpath 'com.android.tools.build:gradle:4.0.2'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
and downgrade the gradle version in gradle.properties to 6.4.1:
distributionUrl=https\://services.gradle.org/distributions/gradle-6.4.1-all.zip

Error while trying to build flutter project

I am facing problems with the build of my apps(the old ones are working but all my new projects are receiving this message)
i already tried rebooting my pc and reinstalling flutter, but this doesn't change the error, and i can't find the solution anywhere
Launching lib\main.dart on Android SDK built for x86 in debug mode...
Running Gradle task 'assembleDebug'...
'D:\projects\CalendarProject' is not recognized as an internal or external command,
operable program or batch file.
Exception: Gradle task assembleDebug failed with exit code 1
this projects\CalendarProject is a old project, but every project i try to build i receive this message pointing to D:\projects\CalendarProject
also my flutter doctor seems perfectly fine
[√] Flutter (Channel stable, 1.20.4, on Microsoft Windows [Version 10.0.18363.1082], locale en-US)
• Flutter version 1.20.4 at C:\src\flutter
• Framework revision fba99f6cf9 (4 days ago), 2020-09-14 15:32:52 -0700
• Engine revision d1bc06f032
• Dart version 2.9.2
[!] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
• Android SDK at D:\android\AndroidVirtual
• Platform android-29, build-tools 29.0.3
• ANDROID_SDK_ROOT = D:\android\AndroidVirtual
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)
! Some Android licenses not accepted. To resolve this, run: flutter doctor --android-licenses
[√] Android Studio (version 3.5)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin version 44.0.1
• Dart plugin version 191.8593
• Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)
[!] IntelliJ IDEA Community Edition (version 2019.1)
• IntelliJ at C:\Users\Joâo Pedro\IntelliJ IDEA Community Edition 2019.1.3
X Flutter plugin not installed; this adds Flutter specific functionality.
X Dart plugin not installed; this adds Dart specific functionality.
• For information about installing plugins, see
https://flutter.dev/intellij-setup/#installing-the-plugins
[√] VS Code (version 1.49.0)
• VS Code at C:\Users\Joâo Pedro\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.14.1
[√] Connected device (1 available)
• Android SDK built for x86 (mobile) • emulator-5554 • android-x86 • Android 10 (API 29) (emulator)
I think it is a config in android folder that is generating this error, but can't imagine what could it be

Are you using flutter in android studio? if so, try opening the project in "vs code", there seems to be a problem with flutter in android studio...

Solved:
the folder that i was using to create projects was inside a folder called "D:\projects\CalendarProject(V3)" (exemple:D:\projects\CalendarProject(V3)\flutter_app)
, don't know is it is a android sdk or flutter bug, but apperently one of them thought CalendarProject(V3) was a function and was trying to run it. this explains the message
'D:\projects\CalendarProject' is not recognized as an internal or external command,
operable program or batch file.
Fixed by changing the directory
you can recreate the error with:
>>mkdir teste(v3)
>>cd "teste(v3)"
>>flutter create app
>>cd app
>>flutter build apk

Flutter Could not resolve project :shared_preferences Required by: project :shared_preferences

I have a flutter project which is working fine on another machine. When I cloned the project to my machine I got this error
Could not resolve all task dependencies for configuration
':shared_preferences:debugCompileClasspath'. Could not resolve project
:shared_preferences_macos. Required by: project :shared_preferences
Unable to find a matching configuration of project :shared_preferences_macos:
None of the consumable configurations have attributes. Could not resolve project :shared_preferences_web. Required by: project
:shared_preferences
Unable to find a matching configuration of project :shared_preferences_web:
None of the consumable configurations have attributes.
This is my flutter doctor -v
[√] Flutter (Channel stable, v1.12.13+hotfix.9, on Microsoft Windows
[Version 10.0.18362.900], locale en-US)
• Flutter version 1.12.13+hotfix.9 at C:\flutter
• Framework revision f139b11009 (3 months ago), 2020-03-30 13:57:30 -0700
• Engine revision af51afceb8
• Dart version 2.7.2
[√] Android toolchain - develop for Android devices (Android SDK
version 29.0.2)
• Android SDK at C:\Users\Administrator.SHADY-LAPTOP\AppData\Local\Android\sdk
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-29, build-tools 29.0.2
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)
• All Android licenses accepted.
[√] Android Studio (version 3.5)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin version 39.0.3
• Dart plugin version 191.8423
• Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)
[√] VS Code (version 1.41.1)
• VS Code at C:\Users\Administrator.SHADY-LAPTOP\AppData\Local\Programs\Microsoft
VS Code
• Flutter extension version 3.7.1
[√] Connected device (1 available)
• Android SDK built for x86 • emulator-5554 • android-x86 • Android 9 (API 28) (emulator)
• No issues found!

After an extensive search, I noticed that the flutter cache folder seems to be corrupted
I run the command flutter pub cache repair and I took a while to download all the cache folder which contains all the packages that you have a cache for.
Finally, the issue is resolved.

I think this has to do with some project updates. You can try this if you still havent got an answer...
Put the below code into the pubsec.yaml file ...
shared_preferences: ^0.5.6
url_launcher: ^5.4.0