[webview_flutter_web] runJavaScript is not implemented on the web platform #173899
Description
Steps to reproduce
- Add
webViewController.runJavaScript('''document.body.innerText='It works!';'''). - Notice red error message.
Expected results
It should replace the web view content with "It works!".
Actual results
It shows an error in browser and console:
The following UnimplementedError was thrown building RunJavaScript(dirty):
runJavaScript is not implemented on the current platform
Code sample
Code sample
import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:webview_flutter_web/webview_flutter_web.dart';
void main() {
runApp(const RunJavaScript());
}
class RunJavaScript extends StatelessWidget {
const RunJavaScript({super.key});
@override
Widget build(BuildContext context) {
var webViewController = WebViewController.fromPlatform(
WebWebViewController(WebWebViewControllerCreationParams()),
);
webViewController.loadHtmlString('''<html><head>
<title>WebWebView</title>
</head><body>
It doesn't work!
</body></html>''');
webViewController.runJavaScript('''
document.body.innerText = 'It works!';
''');
return SizedBox(
height: 480,
child: WebViewWidget(controller: webViewController),
);
}
}Screenshots or Video
Screenshots / Video demonstration
[Upload media here]
Logs
Logs
flutter run -d chrome --verbose
[ +95 ms] Unable to locate an Android SDK.
[ +15 ms] executing: sysctl hw.optional.arm64
[ +6 ms] Exit code 1 from: sysctl hw.optional.arm64
[ ] sysctl: unknown oid 'hw.optional.arm64'
...
[ +118 ms] executing: sysctl hw.optional.arm64
[ +8 ms] Exit code 1 from: sysctl hw.optional.arm64
[ ] sysctl: unknown oid 'hw.optional.arm64'
[ ] executing: xcrun xcodebuild -version
[ +9 ms] Exit code 1 from: xcrun xcodebuild -version
[ ] xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at:
/Library/Developer/CommandLineTools/usr/bin/xcrun
[ +3 ms] Xcode not found. Run 'flutter doctor' for more information.
...
[ +81 ms] executing: xcrun xcodebuild -version
[ +7 ms] Exit code 1 from: xcrun xcodebuild -version
[ ] xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at:
/Library/Developer/CommandLineTools/usr/bin/xcrun
[ +35 ms] Skipping pub get: version match.
[ +140 ms] Found plugin webview_flutter_web at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter_web/
[ +34 ms] Found plugin webview_flutter at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter/
[ +5 ms] Found plugin webview_flutter_wkwebview at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_wkwebview-3.23.0/
[ +10 ms] Found plugin webview_flutter_android at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_android-4.10.0/
[ +78 ms] Found plugin webview_flutter_web at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter_web/
[ +15 ms] Found plugin webview_flutter at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter/
[ +3 ms] Found plugin webview_flutter_wkwebview at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_wkwebview-3.23.0/
[ +2 ms] Found plugin webview_flutter_android at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_android-4.10.0/
[ +28 ms] Skipping generating web_plugin_registrant.dart because it is up-to-date.
[ +52 ms] Found plugin webview_flutter_web at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter_web/
[ +13 ms] Found plugin webview_flutter at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter/
[ +5 ms] Found plugin webview_flutter_wkwebview at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_wkwebview-3.23.0/
[ +3 ms] Found plugin webview_flutter_android at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_android-4.10.0/
[ +195 ms] Launching lib/main.dart on Chrome in debug mode...
[ +5 ms] executing: xcrun xcodebuild -version
[ +10 ms] Exit code 1 from: xcrun xcodebuild -version
[ ] xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at:
/Library/Developer/CommandLineTools/usr/bin/xcrun
[ +5 ms] executing: xcrun simctl list devices booted
[ +173 ms] Initializing file store
[ +23 ms] Skipping target: gen_localizations
[ +7 ms] Skipping target: gen_dart_plugin_registrant
[ +1 ms] Skipping target: _composite
[ +2 ms] complete
[ +1 ms] Updating assets
[ +191 ms] Waiting for connection from debug service on Chrome...
[ +58 ms] Found plugin webview_flutter_web at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter_web/
[ +11 ms] Found plugin webview_flutter at /Volumes/Media.localized/GitHub/flutter_packages/packages/webview_flutter/webview_flutter/
[ +4 ms] Found plugin webview_flutter_wkwebview at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_wkwebview-3.23.0/
[ +2 ms] Found plugin webview_flutter_android at /Users/Sophie/.pub-cache/hosted/pub.dev/webview_flutter_android-4.10.0/
[ +123 ms] shaderc command: [/Volumes/Media.localized/GitHub/flutter/bin/cache/artifacts/engine/darwin-x64/impellerc, --sksl, --iplr, --json,
--sl=build/flutter_assets/shaders/ink_sparkle.frag, --spirv=build/flutter_assets/shaders/ink_sparkle.frag.spirv,
--input=/Volumes/Media.localized/GitHub/flutter/packages/flutter/lib/src/material/shaders/ink_sparkle.frag, --input-type=frag,
--include=/Volumes/Media.localized/GitHub/flutter/packages/flutter/lib/src/material/shaders,
--include=/Volumes/Media.localized/GitHub/flutter/bin/cache/artifacts/engine/darwin-x64/shader_lib]
[ +513 ms] <- reset
[ +7 ms] /Volumes/Media.localized/GitHub/flutter/bin/cache/dart-sdk/bin/dartaotruntime
/Volumes/Media.localized/GitHub/flutter/bin/cache/dart-sdk/bin/snapshots/frontend_server_aot.dart.snapshot --sdk-root
/Volumes/Media.localized/GitHub/flutter/bin/cache/flutter_web_sdk/ --incremental --target=dartdevc --experimental-emit-debug-metadata
-DFLUTTER_VERSION=3.35.1 -DFLUTTER_CHANNEL=stable -DFLUTTER_GIT_URL=https://github.com/flutter/flutter.git -DFLUTTER_FRAMEWORK_REVISION=20f8274939
-DFLUTTER_ENGINE_REVISION=1e9a811bf8 -DFLUTTER_DART_VERSION=3.9.0 --output-dill
/var/folders/bp/v3zn765j28nb9p5gy9vqzdqw0000gp/T/flutter_tools.jBcP3B/flutter_tool.TxpWfY/app.dill --packages
/Volumes/Media.localized/GitHub/flutter_example_app/.dart_tool/package_config.json -Ddart.vm.profile=false -Ddart.vm.product=false --enable-asserts
--track-widget-creation --filesystem-root /var/folders/bp/v3zn765j28nb9p5gy9vqzdqw0000gp/T/flutter_tools.jBcP3B/flutter_tools.U9tY17
--filesystem-scheme org-dartlang-app --initialize-from-dill build/d2976540244dba7be000c4f9690bfe66.cache.dill.track.dill --platform
file:///Volumes/Media.localized/GitHub/flutter/bin/cache/flutter_web_sdk/kernel/ddc_outline.dill --verbosity=error --dartdevc-canary
--dartdevc-module-format=ddc
[ +16 ms] <- compile org-dartlang-app:/web_entrypoint.dart
[+20716 ms] Waiting for connection from debug service on Chrome... (completed in 21.5s)
[ +1 ms] Synced 73.4MB.
[ ] <- accept
[ ] Caching compiled dill
[ +989 ms] Launching Chromium (url = http://localhost:63025, headless = false, skipCheck = false, debugPort = null)
[ ] Will use Chromium executable at /Users/Sophie/Applications/Chromium.app/Contents/MacOS/Chromium
[ +85 ms] Using Chromium 141.0.7360.0
[ +326 ms] executing: sysctl hw.optional.arm64
[ +7 ms] Exit code 1 from: sysctl hw.optional.arm64
[ ] sysctl: unknown oid 'hw.optional.arm64'
[ +461 ms] [CHROME]: [34820:1367111:0816/112259.125622:ERROR:net/cert/internal/trust_store_mac.cc:807] Error parsing certificate:
[ +5 ms] [CHROME]: ERROR: Failed parsing extensions
[ ] [CHROME]:
[ +111 ms] [CHROME]:
[ ] [CHROME]: DevTools listening on ws://127.0.0.1:63029/devtools/browser/20ad83cb-1946-4e55-a8c8-92a2ff6dd1f4
[+2018 ms] DwdsInjector: Received request for entrypoint at http://localhost:63025/main_module.bootstrap.js
[ +4 ms] MetadataProvider: Loading debug metadata...
...
[ +23 ms] DwdsInjector: Injected debugging metadata for entrypoint at http://localhost:63025/main_module.bootstrap.js
[+6827 ms] DevHandler: VmService proxy responded with an error:
{jsonrpc: 2.0, id: 3, error: {code: -32602, message: The stream `Timer` is not supported on web devices}}
[+3785 ms] ChromeProxyService: Initializing expression compiler for main_module.bootstrap.js
[ +88 ms] ChromeProxyService: Caching package:flutter/src/widgets/widget_inspector.dart in expression compiler worker
[ +80 ms] DevHandler: Debug service listening on ws://127.0.0.1:63068/tKefbi1AXD8=/ws
[ +20 ms] DevHandler: VmService proxy responded with an error:
{jsonrpc: 2.0, id: 11, error: {code: -32601, message: Method not found, data: {jsonrpc: 2.0, method: _setStreamIncludePrivateMembers, id:
11, params: {streamId: Stdout, includePrivateMembers: false}}}}
[ +22 ms] This app is linked to the debug service: ws://127.0.0.1:63068/tKefbi1AXD8=/ws
[ +3 ms] DevHandler: VmService proxy responded with an error:
{jsonrpc: 2.0, id: 12, error: {code: -32601, message: Method not found, data: {jsonrpc: 2.0, method: _setStreamIncludePrivateMembers, id:
12, params: {streamId: Stderr, includePrivateMembers: false}}}}
[ +18 ms] DevHandler: VmService proxy responded with an error:
{jsonrpc: 2.0, id: 14, error: {code: -32601, message: Method not found, data: {jsonrpc: 2.0, method: _setStreamIncludePrivateMembers, id:
14, params: {streamId: Isolate, includePrivateMembers: false}}}}
[ +5 ms] DevHandler: VmService proxy responded with an error:
{jsonrpc: 2.0, id: 15, error: {code: -32601, message: Method not found, data: {jsonrpc: 2.0, method: _setStreamIncludePrivateMembers, id:
15, params: {streamId: Extension, includePrivateMembers: false}}}}
[ +10 ms] Debug service listening on ws://127.0.0.1:63068/tKefbi1AXD8=/ws
[ +3 ms] Flutter run key commands.
[ +2 ms] r Hot reload. 🔥🔥🔥
[ +4 ms] R Hot restart.
[ ] h List all available interactive commands.
[ ] d Detach (terminate "flutter run" but leave application running).
[ ] c Clear the screen
[ ] q Quit (terminate the application on the device).
[ ] A Dart VM Service on Chrome is available at: http://127.0.0.1:63068/tKefbi1AXD8=
[ +65 ms] ExpressionEvaluator: Evaluating "() { return true; }" at packages/flutter/src/cupertino/text_form_field_row.dart
[ +19 ms] Starting application from main method in: org-dartlang-app:/web_entrypoint.dart.
[ +45 ms] ExpressionEvaluator: Evaluating JS: "function () {
try {
return ((() => {var sentinel = {}; var output = function() {
let dart = dartDevEmbedder.importLibrary("dart:_runtime", function(lib) {
dart = lib;
});
let dart_rti = dartDevEmbedder.importLibrary("dart:_rti", function(lib) {
dart_rti = lib;
});
let dartx = dartDevEmbedder.importLibrary("dartx", function(lib) {
dartx = lib;
});
var T = {
VoidTobool: () => (T.VoidTobool = dart.constFn(dart_rti._Universe.eval(dart.typeUniverse, "core|bool()", true)))()
};
return dart.fn(() => true, T.VoidTobool());
}(); if (output === sentinel) throw Error("Value not found in scope");return output?._boundMethod || output;})())();
} catch (error) {
return error.name + ": " + error.message;
}
}" with scope: {}
[ +31 ms] ExpressionEvaluator: Evaluated "() { return true; }" to "{type: boolean, value: true}"
[+1936 ms] The Flutter DevTools debugger and profiler on Chrome is available at: http://127.0.0.1:9101?uri=http://127.0.0.1:63068/tKefbi1AXD8=
[+2486 ms] ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
[ +58 ms] The following UnimplementedError was thrown building RunJavaScript(dirty):
[ ] runJavaScript is not implemented on the current platform
[ ] The relevant error-causing widget was:
[ ] RunJavaScript
[ ] RunJavaScript:file:///Volumes/Media.localized/GitHub/flutter_example_app/lib/main.dart:45:49
[ ] When the exception was thrown, this was the stack:
[ ] dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 274:3 throw_
[ ] package:webview_flutter_platform_interface/src/platform_webview_controller.dart 192:5 runJavaScript
[ ] package:webview_flutter/src/webview_controller.dart 245:21 runJavaScript
[ ] package:flutter_example_app/run_java_script.dart 23:22 build
[ ] package:flutter/src/widgets/framework.dart 5791:22 build
[ ] package:flutter/src/widgets/framework.dart 5723:15 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ ] package:flutter/src/widgets/framework.dart 5705:5 [_firstBuild]
[ ] package:flutter/src/widgets/framework.dart 5699:5 mount
[ ] ... Normal element mounting (24 frames)
[ ] package:flutter/src/widgets/framework.dart 4548:15 inflateWidget
[ ] package:flutter/src/widgets/framework.dart 7169:36 inflateWidget
[ ] package:flutter/src/widgets/framework.dart 7185:32 mount
[ ] ... Normal element mounting (188 frames)
[ ] package:flutter/src/widgets/framework.dart 4548:15 inflateWidget
[ ] package:flutter/src/widgets/framework.dart 7169:36 inflateWidget
[ ] package:flutter/src/widgets/framework.dart 4004:18 updateChild
[ ] package:flutter/src/widgets/framework.dart 4203:32 updateChildren
[ ] package:flutter/src/widgets/framework.dart 7202:17 update
[ +2 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ ] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5884:11 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +2 ms] package:flutter/src/widgets/framework.dart 5909:5 update
[ ] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ ] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ ] package:flutter/src/widgets/framework.dart 6051:5 update
[ ] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ ] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +6 ms] package:flutter/src/widgets/framework.dart 6051:5 update
[ +3 ms] package:flutter/src/widgets/inherited_notifier.dart 108:11 update
[ +4 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +4 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ +8 ms] package:flutter/src/widgets/framework.dart 5884:11 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +5 ms] package:flutter/src/widgets/framework.dart 5909:5 update
[ +2 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +5 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ +1 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +5 ms] package:flutter/src/widgets/framework.dart 6051:5 update
[ ] package:flutter/src/widgets/inherited_notifier.dart 108:11 update
[ +7 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +4 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5884:11 performRebuild
[ +10 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +4 ms] package:flutter/src/widgets/framework.dart 5909:5 update
[ +10 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ ] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ +6 ms] package:flutter/src/widgets/framework.dart 5884:11 performRebuild
[ +3 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +2 ms] package:flutter/src/widgets/framework.dart 5909:5 update
[ +7 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +2 ms] package:flutter/src/widgets/framework.dart 7025:14 update
[ +1 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +5 ms] package:flutter/src/widgets/framework.dart 7025:14 update
[ ] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +8 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ +4 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +7 ms] package:flutter/src/widgets/framework.dart 6051:5 update
[ ] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +1 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ +14 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +4 ms] package:flutter/src/widgets/framework.dart 6051:5 update
[ +11 ms] package:flutter/src/widgets/framework.dart 3982:14 updateChild
[ +7 ms] package:flutter/src/widgets/framework.dart 5747:16 performRebuild
[ ] package:flutter/src/widgets/framework.dart 5884:11 performRebuild
[ +10 ms] package:flutter/src/widgets/framework.dart 5435:7 rebuild
[ +3 ms] package:flutter/src/widgets/framework.dart 2695:14 [_tryRebuild]
[ +5 ms] package:flutter/src/widgets/framework.dart 2752:11 [_flushDirtyElements]
[ +9 ms] package:flutter/src/widgets/framework.dart 3056:17 buildScope
[ ] package:flutter/src/widgets/binding.dart 1259:9 drawFrame
[ +11 ms] package:flutter/src/rendering/binding.dart 495:5 [_handlePersistentFrameCallback]
[ +5 ms] dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
[ +3 ms] package:flutter/src/scheduler/binding.dart 1434:7 [_invokeFrameCallback]
[ +2 ms] package:flutter/src/scheduler/binding.dart 1347:9 handleDrawFrame
[ +5 ms] package:flutter/src/scheduler/binding.dart 1200:5 [_handleDrawFrame]
[ +2 ms] dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
[ +3 ms] lib/_engine/engine/platform_dispatcher.dart 1522:5 invoke
[ +11 ms] lib/_engine/engine/platform_dispatcher.dart 265:5 invokeOnDrawFrame
[ +6 ms] lib/_engine/engine/frame_service.dart 192:32 [_renderFrame]
[ +9 ms] lib/_engine/engine/frame_service.dart 99:9 <fn>
[ ] dart-sdk/lib/async/zone.dart 1849:54 runUnary
[ +3 ms] dart-sdk/lib/async/zone.dart 1804:26 <fn>
[ +5 ms] dart-sdk/lib/_internal/js_dev_runtime/patch/js_allow_interop_patch.dart 224:27 _callDartFunctionFast1
[ +13 ms] ════════════════════════════════════════════════════════════════════════════════════════════════════Flutter Doctor output
Doctor output
[✓] Flutter (Channel stable, 3.35.1, on macOS 12.7.6 21H1320 darwin-x64, locale en-DE) [171ms]
• Flutter version 3.35.1 on channel stable at /Volumes/Media.localized/GitHub/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 20f8274939 (2 days ago), 2025-08-14 10:53:09 -0700
• Engine revision 1e9a811bf8
• Dart version 3.9.0
• DevTools version 2.48.0
• Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations,
enable-lldb-debugging
[✗] Android toolchain - develop for Android devices [94ms]
✗ Unable to locate Android SDK.
Install Android Studio from: https://developer.android.com/studio/index.html
On first launch it will assist you in installing the Android SDK components.
(or visit https://flutter.dev/to/macos-android-setup for detailed instructions).
If the Android SDK has been installed to a custom location, please use
`flutter config --android-sdk` to update to that location.
[✗] Xcode - develop for iOS and macOS [133ms]
✗ Xcode installation is incomplete; a full installation is necessary for iOS and macOS development.
Download at: https://developer.apple.com/xcode/
Or install Xcode via the App Store.
Once installed, run:
sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
sudo xcodebuild -runFirstLaunch
✗ CocoaPods not installed.
CocoaPods is a package manager for iOS or macOS platform code.
Without CocoaPods, plugins will not work on iOS or macOS.
For more info, see https://flutter.dev/to/platform-plugins
For installation instructions, see https://guides.cocoapods.org/using/getting-started.html#installation
[✓] Chrome - develop for the web [38ms]
• CHROME_EXECUTABLE = /Users/Sophie/Applications/Chromium.app/Contents/MacOS/Chromium
[!] Android Studio (not installed) [36ms]
• Android Studio not found; download from https://developer.android.com/studio/index.html
(or visit https://flutter.dev/to/macos-android-setup for detailed instructions).
[✓] Connected device (2 available) [225ms]
• macOS (desktop) • macos • darwin-x64 • macOS 12.7.6 21H1320 darwin-x64
• Chrome (web) • chrome • web-javascript • Chromium 141.0.7360.0
[✓] Network resources [452ms]
• All expected network resources are available.
! Doctor found issues in 3 categories.