bug: webview_flutter_android 4.10.2 (overridden) breaks build

[SamYuan1990]

Duplicate Check

• I have searched the opened issues and there are no duplicates

Describe the bug

With in 24 hours, webview_flutter_android released 4.10.2 which break flet build.

https://github.com/SamYuan1990/i18n-agent-action/actions/runs/17603702651/job/50010346530?pr=99#step:7:216

Code sample

https://github.com/SamYuan1990/i18n-agent-action/actions/runs/17603702651/job/50010346530?pr=99#step:7:216

To reproduce

https://github.com/SamYuan1990/i18n-agent-action/actions/runs/17603702651/job/50010346530?pr=99#step:7:216

Expected behavior

No response

Screenshots / Videos

Captures

[Upload media here]

Operating System

macOS

Operating system details

in fact, win and linux also ...

Flet version

0.28.3

Regression

Yes, it used to work in a previous Flet version (please specify the version in additional details)

Suggestions

No response

Logs

Logs

[Paste your logs here]

Additional details

No response

[SamYuan1990]

is there any way to lock webview_flutter_android version?

[ReYaNOW]

Temporarily fixed it with such block in pubspec.yaml in build/flutter/

dependency_overrides:
flet: 0.28.3
serious_python:
git:
path: src/serious_python
ref: hidden-files-fix
url: https://github.com/flet-dev/serious-python.git
wakelock_plus: ^1.2.10
web: ^1.0.0
webview_flutter_android: 4.10.1
window_manager: ^0.4.3

Here i set webview_flutter_android to 4.10.1 this is only required part

[SamYuan1990]

Temporarily fixed it with such block in pubspec.yaml in build/flutter/

dependency_overrides: flet: 0.28.3 serious_python: git: path: src/serious_python ref: hidden-files-fix url: https://github.com/flet-dev/serious-python.git wakelock_plus: ^1.2.10 web: ^1.0.0 webview_flutter_android: 4.10.1 window_manager: ^0.4.3

Here i set webview_flutter_android to 4.10.1 this is only required part

ref flet-dev/flet-build-template#50 (comment)

[ReYaNOW]

Temporarily fixed it with such block in pubspec.yaml in build/flutter/

dependency_overrides: flet: 0.28.3 serious_python: git: path: src/serious_python ref: hidden-files-fix url: https://github.com/flet-dev/serious-python.git wakelock_plus: ^1.2.10 web: ^1.0.0 webview_flutter_android: 4.10.1 window_manager: ^0.4.3

Here i set webview_flutter_android to 4.10.1 this is only required part

ref flet-dev/flet-build-template#50 (comment)

yes, thats a better solution i didnt know that u can override flutter deps via pyproject.toml

[haoyunkaihappy]

it works to build the ipa, but when i distribute the app and use the app on my iphone, webview page raise error

[DarkWolf260]

Just add this code to your pyproject.toml file.

[tool.flet.flutter.pubspec.dependency_overrides]
webview_flutter_android = "4.10.1"

It works while they add support for new versions of this dependency.

[traashbaat]

(.venv) PS C:\Users\user\PycharmProjects\flet> flet build apk
[21:56:00] Flutter 3.29.2 installed ✅
[21:56:01] JDK installed ✅
Android SDK installed ✅
[21:56:06] Created Flutter bootstrap project from gh:flet-dev/flet-build-template with ref "0.28.3" ✅
[21:57:11] Packaged Python app ✅
[22:00:02] Customized app icons ✅
[22:00:10] Generated app icons ✅
Customized app splash images ✅
[22:00:14] Generated splash screens ✅
[22:01:30] Resolving dependencies...
Downloading packages...
archive 3.6.1 (4.0.7 available)
characters 1.4.0 (1.4.1 available)
device_info_plus 11.5.0 (12.1.0 available)
fl_chart 0.69.2 (1.1.1 available)
! flet 0.28.3 (overridden)
flutter_lints 2.0.3 (6.0.0 available)
flutter_native_splash 2.4.4 (2.4.6 available)
image 4.3.0 (4.5.4 available)
js 0.6.7 (0.7.2 available)
lints 2.1.1 (6.0.0 available)
material_color_utilities 0.11.1 (0.13.0 available)
meta 1.16.0 (1.17.0 available)
package_info_plus 8.3.1 (9.0.0 available)
petitparser 6.1.0 (7.0.1 available)
sensors_plus 4.0.2 (7.0.0 available)
sensors_plus_platform_interface 1.2.0 (2.0.1 available)
! serious_python 0.9.3 from git https://github.com/flet-dev/serious-python.git at 211d3f in src/serious_python (overridden)
toml 0.15.0 (0.16.0 available)
url_strategy 0.2.0 (discontinued)
! wakelock_plus 1.3.3 (overridden) (1.4.0 available)
! web 1.1.1 (overridden)
web_socket_channel 2.4.5 (3.0.3 available)
! webview_flutter_android 4.10.1 (overridden) (4.10.2 available)
! window_manager 0.4.3 (overridden) (0.5.1 available)
xml 6.5.0 (6.6.1 available)
Got dependencies!
1 package is discontinued.
22 packages have newer versions incompatible with dependency constraints.
Try flutter pub outdated for more information.
Running Gradle task 'assembleRelease'...
Gradle build config:
minSdkVersion: 24
targetSdkVersion: 36
versionCode: 1
versionName: 0.1.0
Running Gradle task 'assembleRelease'... 72,5s

       Warning: Flutter support for your project's Android Gradle Plugin version (Android Gradle Plugin version 8.3.1) will soon be     
       dropped. Please upgrade your Android Gradle Plugin version to a version of at least Android Gradle Plugin version 8.6.0 soon.    
       Alternatively, use the flag "--android-skip-build-dependency-validation" to bypass this check.                                   
                                                                                                                                        
       Potential fix: Your project's AGP version is typically defined in the plugins block of the `settings.gradle` file                
       (C:\Users\user\PycharmProjects\flet\build\flutter\android/settings.gradle), by a plugin with the id of com.android.application.  
       If you don't see a plugins block, your project was likely created with an older template version. In this case it is most likely 
       defined in the top-level build.gradle file (C:\Users\user\PycharmProjects\flet\build\flutter\android/build.gradle) by the        
       following line in the dependencies block of the buildscript: "classpath 'com.android.tools.build:gradle:<version>'".             
                                                                                                                                        
       Warning: Flutter support for your project's Kotlin version (1.9.24) will soon be dropped. Please upgrade your Kotlin version to a
       version of at least 2.1.0 soon.                                                                                                  
       Alternatively, use the flag "--android-skip-build-dependency-validation" to bypass this check.                                   
                                                                                                                                        
       Potential fix: Your project's KGP version is typically defined in the plugins block of the `settings.gradle` file                
       (C:\Users\user\PycharmProjects\flet\build\flutter\android/settings.gradle), by a plugin with the id of                           
       org.jetbrains.kotlin.android.                                                                                                    
       If you don't see a plugins block, your project was likely created with an older template version, in which case it is most likely
       defined in the top-level build.gradle file (C:\Users\user\PycharmProjects\flet\build\flutter\android/build.gradle) by the        
       ext.kotlin_version property.                                                                                                     
                                                                                                                                        
       Warning: SDK processing. This version only understands SDK XML versions up to 3 but an SDK XML file of version 4 was encountered.
       This can happen if you use versions of Android Studio and the command-line tools that were released at different times.          
       ../../../../AppData/Local/Pub/Cache/hosted/pub.dev/flet-0.28.3/lib/src/utils/theme.dart:144:9: Error: The argument type          
       'BottomAppBarTheme?' can't be assigned to the parameter type 'BottomAppBarThemeData?'.                                           
        - 'BottomAppBarTheme' is from 'package:flutter/src/material/bottom_app_bar_theme.dart'                                          
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/bottom_app_bar_theme.dart').                                      
        - 'BottomAppBarThemeData' is from 'package:flutter/src/material/bottom_app_bar_theme.dart'                                      
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/bottom_app_bar_theme.dart').                                      
               parseBottomAppBarTheme(theme, json?["bottom_app_bar_theme"]),                                                            
               ^                                                                                                                        
       ../../../../AppData/Local/Pub/Cache/hosted/pub.dev/flet-0.28.3/lib/src/utils/theme.dart:818:28: Error: A value of type           
       'AppBarThemeData' can't be returned from a function with return type 'AppBarTheme?'.                                             
        - 'AppBarThemeData' is from 'package:flutter/src/material/app_bar_theme.dart'                                                   
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/app_bar_theme.dart').                                             
        - 'AppBarTheme' is from 'package:flutter/src/material/app_bar_theme.dart'                                                       
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/app_bar_theme.dart').                                             
         return theme.appBarTheme.copyWith(                                                                                             
                                  ^                                                                                                     
       ../../../../AppData/Local/Pub/Cache/hosted/pub.dev/flet-0.28.3/lib/src/utils/theme.dart:842:34: Error: A value of type           
       'BottomAppBarThemeData' can't be returned from a function with return type 'BottomAppBarTheme?'.                                 
        - 'BottomAppBarThemeData' is from 'package:flutter/src/material/bottom_app_bar_theme.dart'                                      
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/bottom_app_bar_theme.dart').                                      
        - 'BottomAppBarTheme' is from 'package:flutter/src/material/bottom_app_bar_theme.dart'                                          
       ('../../../../flutter/3.29.2/packages/flutter/lib/src/material/bottom_app_bar_theme.dart').                                      
         return theme.bottomAppBarTheme.copyWith(                                                                                       
                                        ^                                                                                               
       Target kernel_snapshot_program failed: Exception                                                                                 
                                                                                                                                        
                                                                                                                                        
       FAILURE: Build failed with an exception.                                                                                         
                                                                                                                                        
       * What went wrong:                                                                                                               
       Execution failed for task ':app:compileFlutterBuildRelease'.                                                                     
       > Process 'command 'C:\Users\user\flutter\3.29.2\bin\flutter.bat'' finished with non-zero exit value 1                           
                                                                                                                                        
       * 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 1m 11s                                                                                                           
       Gradle task assembleRelease failed with exit code 1                                                                              

[22:01:34] Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.35.4, on Microsoft Windows [Version 10.0.26100.6584], locale ru-RU)
[√] Windows Version (Windows 11 or higher, 24H2, 2009)
[√] Android toolchain - develop for Android devices (Android SDK version 36.1.0-rc1)
[√] Chrome - develop for the web
[X] Visual Studio - develop Windows apps
X Visual Studio not installed; this is necessary to develop Windows apps.
Download at https://visualstudio.microsoft.com/downloads/.
Please install the "Desktop development with C++" workload, including all of its default components
[√] Android Studio (version 2025.1.3)
[√] Connected device (3 available)
[√] Network resources

       ! Doctor found issues in 1 category.                                                                                             

╭──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮│ Error building Flet app - see the log of failed command above. │

@DarkWolf260 It didn't help me.

name = "xdxdxd"
version = "0.1.0"
description = ""
readme = "README.md"
requires-python = ">=3.9"
authors = [
    { name = "Flet developer", email = "you@example.com" }
]
dependencies = [
  "flet==0.28.3"
]

[tool.flet]
# org name in reverse domain name notation, e.g. "com.mycompany".
# Combined with project.name to build bundle ID for iOS and Android apps
org = "com.mycompany"

# project display name that is used as an app title on Android and iOS home screens,
# shown in window titles and about app dialogs on desktop.
product = "xdxdxd"

# company name to display in about app dialogs
company = "Flet"

# copyright text to display in about app dialogs
copyright = "Copyright (C) 2025 by Flet"

[tool.flet.app]
path = "src"

[tool.uv]
dev-dependencies = [
    "flet[all]==0.28.3",
]

[tool.poetry]
package-mode = false

[tool.poetry.group.dev.dependencies]
flet = {extras = ["all"], version = "0.28.3"}

[tool.flet.android]
min_sdk_version = 24

[tool.flet.flutter.pubspec.dependency_overrides]
webview_flutter_android = "4.10.1"```

[SquareStalker]

Hello. Man, I had the same issue. Actually, I was searching for help too and that's how I ended up here. I'm not an expert though, I'm a rookie in coding stuff. But I could have found a solution; I hope it could work for you.

First, open the file where you got the issue (first you have to build the app to have the build folder). It should be this location for you: '../../../../AppData/Local/Pub/Cache/hosted/pub.dev/flet-0.28.3/lib/src/utils/theme.dart'

Second, find and change every instance of the classes which are causing the errors in the changelog. For example, one of them is: 'BottomAppBarTheme', you have to change it for 'BottomAppBarThemeData' instead.

Last, you should enter via terminal to the flutter folder ({project_folder}/build/flutter) and then execute the command 'flutter clean' and then 'flutter pub get. Once you do all this stuff, you can launch again (from the project folder) the build apk.

That's what I did and It works just fine, and it feels satisfying since I've been experiencing this issue for 2 weeks straight. 💀💀👌

PS: I'm not an english speaker so... apologies for the inconveniences on my behalf.

[traashbaat]

@SquareStalker thx bro, i love you!

[Realcoder70]

AppBarTheme cannot be returned happens when your flet version mismatch your flutter version so update your flutter to match or downgrade.

For flet-webview version error, another way round and removing removing the flet-webview from override section in the pub.spec file and specifying a fitting version at the dependency section.