与 Metro 服务器断开连接

Question

我不断收到此错误：

Disconnected from the Metro server.
at node_modules\react-native\Libraries\LogBox\LogBox.js:117:10 in registerWarning
at node_modules\react-native\Libraries\LogBox\LogBox.js:63:8 in warnImpl
at node_modules\react-native\Libraries\LogBox\LogBox.js:36:4 in console.warn
at node_modules\expo\build\environment\react-native-logs.fx.js:18:4 in warn
at node_modules\react-native\Libraries\Utilities\HMRClient.js:260:4 in setHMRUnavailableReason
at node_modules\react-native\Libraries\Utilities\HMRClient.js:234:29 in client.on$argument_1
at node_modules\eventemitter3\index.js:180:21 in emit
at node_modules\metro\src\lib\bundle-modules\HMRClient.js:118:6 in _ws.onclose
at node_modules\event-target-shim\dist\event-target-shim.js:818:20 in EventTarget.prototype.dispatchEvent
at node_modules\react-native\Libraries\WebSocket\WebSocket.js:246:8 in _eventEmitter.addListener$argument_1
at node_modules\react-native\Libraries\vendor\emitter\EventEmitter.js:189:10 in emit
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:416:4 in __callFunction
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:109:6 in __guard$argument_0
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:364:10 in __guard
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:108:4 in callFunctionReturnFlushedQueue
at [native code]:null in callFunctionReturnFlushedQueue

我正在使用 React Native Expo，出于某种原因，这发生在 fetch 请求或共享文件之后。它仅在我执行此 function 之后或时发生。这是function：

const exportReport = async () => {
    if (validate()) {
      setLoading(true);
      let token = await SecureStore.getItemAsync("token");
      return await fetch("https://notarealapi.herokuapp.com/api/export", {
        method: "POST",
        headers: {
          "content-type": "application/json",
          Authorization: `JWT ${JSON.parse(token)}`,
        },
        body: JSON.stringify({ note: note, mission: value }),
      })
        .then((res) => res.json())
        .then(async (json) => {
          if (json.hasOwnProperty("msg")) {
            Alert.alert(json.msg);
          } else {
            setLoading(false);
            console.log(json);
            const reportUrl = "data:application/pdf;base64," + String(json.pdf);
            console.log(reportUrl);
            const base64Code = reportUrl.split(
              "data:application/pdf;base64,"
            )[1];
            const filename = FileSystem.documentDirectory + "report.pdf";
            console.log(base64Code);
            await FileSystem.writeAsStringAsync(filename, base64Code, {
              encoding: FileSystem.EncodingType.Base64,
            });
            const _mediaResult = await MediaLibrary.saveToLibraryAsync(
              filename
            );
            await Sharing.shareAsync(filename);
          }
        })
        .catch((error) => console.error(error));
    }
  };

另外，我认为这个错误与Logbox有关，但除此之外，我一无所知。

错误只发生在这个函数中。