dart:tml and dart:js not found error flutter

Question

I am trying to make a speech to text and text to speech feature in my chat app for making voice messages. I was following this documentation completely https://pub.dev/packages/flutter_tts/example . But I had to import another library called flutter_tts_web.dart .I thought it should not be a big deal but it seems like it is causing the big error. Here is the stacktrace

../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:2:8: Error: Not found: 'dart:html'
import 'dart:html' as html;
       ^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:3:8: Error: Not found: 'dart:js'
import 'dart:js';
       ^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:31:3: Error: Type 'html.SpeechSynthesis' not found.
  html.SpeechSynthesis synth;
  ^^^^^^^^^^^^^^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:32:3: Error: Type 'html.SpeechSynthesisUtterance' not found.
  html.SpeechSynthesisUtterance utterance;
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:31:8: Error: 'SpeechSynthesis' isn't a type.
  html.SpeechSynthesis synth;
       ^^^^^^^^^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:32:8: Error: 'SpeechSynthesisUtterance' isn't a type.
  html.SpeechSynthesisUtterance utterance;
       ^^^^^^^^^^^^^^^^^^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:37:17: Error: Method not found: 'SpeechSynthesisUtterance'.
    utterance = html.SpeechSynthesisUtterance();
                ^^^^^^^^^^^^^^^^^^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:38:18: Error: Getter not found: 'window'.
    synth = html.window.speechSynthesis;
                 ^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:156:63: Error: 'JsArray' isn't a type.
        context['speechSynthesis'].callMethod('getVoices') as JsArray<dynamic>;
                                                              ^^^^^^^
../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart:156:9: Error: The getter 'context' isn't defined for the class 'FlutterTtsPlugin'.
 - 'FlutterTtsPlugin' is from 'package:flutter_tts/flutter_tts_web.dart' ('../../AppData/Local/Pub/Cache/hosted/pub.dartlang.org/flutter_tts-1.2.6/lib/flutter_tts_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
        context['speechSynthesis'].callMethod('getVoices') as JsArray<dynamic>;
        ^^^^^^^
/C:/flutter/packages/flutter_web_plugins/lib/src/plugin_registry.dart:29:5: Error: Method not found: 'webOnlySetPluginHandler'.
    ui.webOnlySetPluginHandler(_binaryMessenger.handlePlatformMessage);
    ^^^^^^^^^^^^^^^^^^^^^^^
Unhandled exception:
FileSystemException(uri=
org-dartlang-untranslatable-uri:dart%3Ahtml; message=StandardFileSystem only supports file:* and data:* URIs)
#0      StandardFileSystem.entityForUri (package:front_end/src/api_proto
type/standard_file_system.dart:33:7)
#1      asFileUri (package:vm/kernel_front_end.dart:659:37)
#2      writeDepfile (package:vm/kernel_front_end.dart:853:21)
<asynchronous suspension>
#3      FrontendCompiler.compile (package:frontend_server/frontend_server.dart:574:15)
<asynchronous suspension>
#4      _FlutterFrontendCompiler.compile (package:flutter_frontend_server/server.dart:43:22)
#5      starter (package:flutter_frontend_server/server.dart:182:27)
#6      main (file:///C:/b/s/w/ir/cache/builder/src/flutter/flutter_frontend_server/bin/starter.dart:9:30)
#7      _startIsolate.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:299:32)
#8      _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)



FAILURE: Build failed with an exception.

* Where:
Script 'C:\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 896

* What went wrong:
Execution failed for task ':app:compileFlutterBuildDebug'.
> Process 'command 'C:\flutter\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 38s
Exception: Gradle task assembleDebug failed with exit code 1

I tried to remove the file but the variable Tts State depends on the web file. A;so tried flutter clean and switching to beta chanel. Please help as soon as possible as this is for a hackathon and I have 8 hours left. I'll provide any code neccessary almost instantly

Answer 1

我认为这是因为未安装 dart，请确保您正确安装了 dart，并在安装 dart 后使用以下命令。

pub get