使用 webdev serve 指令启动 flutter web 项目失败，怎么处理？没有找到相似解决方案

Question

webdev build构建可以成功通过：

PS D:\www\flutter_web_demo> webdev build
[INFO] Reading cached asset graph completed, took 242ms
[INFO] Checking for updates since last build completed, took 694ms
[INFO] Running build completed, took 235ms
[INFO] Caching finalized dependency graph completed, took 123ms
[INFO] Reading manifest at build\.build.manifest completed, took 16ms
[INFO] Deleting previous outputs in `build` completed, took 569ms
[INFO] Creating merged output dir `build` completed, took 2.9s
[INFO] Writing asset manifest completed, took 153ms
[INFO] Succeeded after 4.3s with 0 outputs (0 actions)

执行运行指令不能成功：

PS D:\www\flutter_web_demo> webdev serve
[INFO] Reading cached asset graph completed, took 361ms
[INFO] Checking for updates since last build completed, took 923ms
[INFO] Starting resource servers...Unhandled exception:
SocketException: Failed to create server socket (OS Error: Failed to start accept), address = localhost, port = 8080
#0      _NativeSocket.bind (dart:io-patch/socket_patch.dart:591:7)
<asynchronous suspension>
#1      _RawServerSocket.bind (dart:io-patch/socket_patch.dart:1206:26)
#2      _ServerSocket.bind (dart:io-patch/socket_patch.dart:1466:29)
#3      ServerSocket.bind (dart:io-patch/socket_patch.dart:1457:26)
#4      _HttpServer.bind (dart:_http/http_impl.dart:2520:25)
#5      HttpServer.bind (dart:_http:227:19)
#6      WebDevServer.start (package:webdev/src/serve/webdev_server.dart:81:26)
#7      _AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:49:6)
#8      WebDevServer.start (package:webdev/src/serve/webdev_server.dart:53:36)
#9      ServerManager.start (package:webdev/src/serve/server_manager.dart:22:38)
#10     _AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:49:6)
#11     ServerManager.start (package:webdev/src/serve/server_manager.dart:18:37)
#12     _startServerManager (package:webdev/src/serve/dev_workflow.dart:85:27)
#13     _AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:49:6)
#14     _startServerManager (package:webdev/src/serve/dev_workflow.dart:66:42)
#15     DevWorkflow.start (package:webdev/src/serve/dev_workflow.dart:186:31)
#16     _RootZone.runUnary (dart:async/zone.dart:1379:54)
#17     _FutureListener.handleValue (dart:async/future_impl.dart:126:18)
#18     Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:639:45)
#19     Future._propagateToListeners (dart:async/future_impl.dart:668:32)
#20     Future._complete (dart:async/future_impl.dart:473:7)
#21     _SyncCompleter.complete (dart:async/future_impl.dart:51:12)
#22     _AsyncAwaitCompleter.complete.<anonymous closure> (dart:async-patch/async_patch.dart:33:20)
#23     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#24     _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
#25     _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:115:13)
#26     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:172:5)

初步认为可能是配置原因或缺少资源引用。
通过日志分析不出问题所在，通过网络也找不到相似的问题及解决方案，盼有 flutter web 开发经验的大神指导！

Answer 1

把启动默认参数主机地址改下， webdev serve --hostname 127.0.0.1

Answer 2

build 不是失败了吗？ 0 outputs (0 actions)

建议clean之后重新运行，看看是否引用了web不支持的库导致编译被跳过了。

Answer 3

setRemFontSize() {

    var remSize = window.innerWidth / 19.2;
    document.querySelector("html").style.fontSize = remSize + "px";
  }
  setRemFontSize();
  window.addEventListener("resize", function() {
    setTimeout(function() {
      setRemFontSize();
    }, 200)