On Android when there are multiple flavors and no --flavor flag is specified then use a default one

On Android, when there are multiple flavors defined, and the user runs the app but does not specify a value for the --flavor flag then the following error is shown:

You must specify a --flavor option to select one of them.

This is implemented like that here: https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/android/gradle.dart#L342

This makes it so that everytime we have to specifiy a value for --flavor.
I would propose when the flag is not specified to just default to the first one.
This will make it faster to start your Flutter app, not having to write --flavor _flavor_ everytime.

Also running into this issue, it is a pain to not be able to just run with default commands. Would be nice to have a default flavor.

+1 Also face the same issue.

@cmwarrington

@cmwarrington, do you know if flutter should be able to move forward on this? I saw your involvement at the following commits, and made a naive guess you might have an idea for this.

Also face the same issue. please give a answer this question.

Hello. I have the same problem.
I fixed it the following way
I use Android Studio.
open Edit Configurations -> build flavor -> enter flavor name (example : develop)

Any work around for this? This is really needed for us.

in vscode you can setup debug configuration

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Flutter Dev",
            "request": "launch",
            "args": ["--flavor", "development"],
            "type": "dart"
        }
    ]
}

@erabti

@erabti If you use Android Studio. You can try my way.
open Edit Configurations -> build flavor -> enter flavor name (example : develop)

Does anybody know how to set default flavor in Bitrise? I am getting the same error when Bitrise is trying to build the app, and I can't find a way to set flavor.

Can this be given a higher priority? This is confusing for almost everyone onboarding a project having flavors, especially when iOS behaves differently, and especially when Flutter gives cryptic error messages that doesn't suggest the flavor is missing?

... especially when Flutter gives cryptic error messages that doesn't suggest the flavor is missing?

Here's the cryptic message in question:

Launching lib/main.dart on sdk gphone64 arm64 in debug mode...
main.dart:1
Exception: Gradle build failed to produce an .apk file. It's likely that this file was generated under /Users/pattobrien/dev/fine_designs/template/src/frontend/build, but the tool couldn't find it.
Exited

This is not a helpful message in the slightest, especially because there is an apk file in that directory, it's just not the name expected.

If a default flavor cannot be selected, then it would be helpful to at least mention what the expected file name is, so that a user can easily spot the difference between the file that does exist vs. the file that the flutter tool is expecting. This seems like a quick win IMO.

Please support this

Not a default, but if you rather make the issue more explicit - you can use the following code to fail the build when it's not specified

gradle.taskGraph.whenReady { taskGraph ->
    if (!project.hasProperty('android.injected.build.model') // ensure we're not in sync mode
        && taskGraph.allTasks.any { it.name.toLowerCase().equals("assembledebug") || it.name.toLowerCase().equals("assemblerelease") }) {
        throw new Exception("Please specify a flavor with --flavor argument")
    }
}

https://stackoverflow.com/a/60197203/3607358

... especially when Flutter gives cryptic error messages that doesn't suggest the flavor is missing?

Here's the cryptic message in question:
Launching lib/main.dart on sdk gphone64 arm64 in debug mode...
main.dart:1
Exception: Gradle build failed to produce an .apk file. It's likely that this file was generated under /Users/pattobrien/dev/fine_designs/template/src/frontend/build, but the tool couldn't find it.
Exited
This is not a helpful message in the slightest, especially because there is an apk file in that directory, it's just not the name expected.

If a default flavor cannot be selected, then it would be helpful to at least mention what the expected file name is, so that a user can easily spot the difference between the file that does exist vs. the file that the flutter tool is expecting. This seems like a quick win IMO.

Does this error mean that it's missing a Flavor name?
Can't the project run by default using flutter run command?

I just bumped into this and with flutter 3.16.x (and gradle 8.2) flutter picks a default flavor (I don't know since which version).

~~By default gradle sorts the flavor names in alphabetical order and picks the first one. Seems like flutter only supports this.~~

In Gradle it is possible to mark a flavor as default, but from my tests flutter ignores it:

flavorDimensions=["version"]
    productFlavors {
        b {
            getIsDefault().set(true)
            // isDefault true
            dimension "version"
        }
        a {
            dimension "version"
        }
    }

When defining this I would expect b as the default ~~, but when running the app with flutter run then it picks a instead.~~

Edit: The alphabetical order trick worked randomly only, could not reproduce between two full builds. So I reduce my points to just: the gradle isDefault setting is ignored. So a default flavor is indeed picked, but I can't figure out how to control which one.

Why setting a default doesn't work

Flutter seems to by default do all flavors.

    productFlavors {
        dev {
            dimension "default"
            resValue "string", "app_name", "Myapp Dev"
            applicationIdSuffix ".dev"
        }
        live {
            dimension "default"
            resValue "string", "app_name", "Myapp"
            applicationIdSuffix null
        }
        beta {
            dimension "default"
            resValue "string", "app_name", "Myapp Beta"
            applicationIdSuffix ".beta"
        }
    }

> rm -r ./build/app/outputs/flutter-apk
> flutter build apk
..snip..
Gradle build failed to produce an .apk file. It's likely that this file was generated under /path/to/project/build, but the tool couldn't find it.
> ls -la build/app/outputs/flutter-apk
-rw-rw-r-- 1 chase chase 29548328 May  9 20:21 app-dev-release.apk
-rw-rw-r-- 1 chase chase 29548326 May  9 20:21 app-beta-release.apk
-rw-rw-r-- 1 chase chase 29548300 May  9 20:21 app-live-release.apk

Contrarily though, appbundle seems to only produce one.

flutter run also fails for me without a flavor

can you please merge this PR? #147968

add `default-flavor` field to flutter pubspec, which will be used as …

document default flavor (#10642)

#147968 will allow users to specify a default-flavor in their pubspec and should be available in the next stable release (whatever comes after 3.22). I believe this satisfies the primary concern/request of this issue.

#139286 tracks the issue of the confusing error message shown when an Android-enabled project has flavors configured but --flavor is not provided.

add `default-flavor` field to flutter pubspec, which will be used as …

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.

Navigation Menu

On Android when there are multiple flavors and no --flavor flag is specified then use a default one #22856

11 remaining items

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

On Android when there are multiple flavors and no --flavor flag is specified then use a default one #22856

Description

Activity

matthewcook333 commented on Dec 7, 2018

royorange commented on Feb 14, 2019

bradyt commented on Aug 19, 2019

mewadaArvind commented on Oct 11, 2019

jackyhieu1211-hn commented on Mar 4, 2020

erabti commented on May 19, 2020

msmaromi commented on May 20, 2020

jackyhieu1211-hn commented on May 20, 2020

nazdream commented on Apr 13, 2021

11 remaining items

marianhlavac commented on Jul 10, 2023

pattobrien commented on Aug 2, 2023

vietstone-ng commented on Aug 8, 2023

giljulio commented on Aug 16, 2023

SilenceCodder commented on Oct 7, 2023

slaci commented on Feb 12, 2024

ChaseGuru commented on May 10, 2024

hasanm08 commented on May 11, 2024

andrewkolos commented on May 22, 2024

github-actions commented on Jun 5, 2024

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions