小编sre*_*ary的帖子

我正在尝试将角度应用程序容器化。这是我的泊坞窗文件

FROM nginx
LABEL author="sreeya"
COPY ./config/nginx.conf /etc/nginx/ngnix.cong

我用了

docker build -t nginx-angular -f nginx.dockerfile .
docker run -p 8080:80 -v $(pwd)/dist:/usr/share/nginx/html nginx-angular

构建成功，但 docker run 陷入困境

start worker process 30

这是完整的输出

/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up …

我试图通过从 API 获取值来填充下拉列表。当我单击下拉菜单时，正在显示值，当我尝试选择一个值时，会引发以下错误

 items.isEmpty || value == null || items.where((DropdownMenuItem<T> item) => item.value == value).length == 1': is not true.

列表中的值不为空

当我尝试删除下拉的“值”属性时，未显示错误但下拉未显示所选值

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:something/Utils/formServices.dart';
import 'package:datetime_picker_formfield/datetime_picker_formfield.dart';
import 'package:intl/intl.dart';
import 'dart:convert';

String insurer;
String package;
List insCat = List();
List insurers = List();
List<DropdownMenuItem> items = [];

class AddOrEditPack extends StatefulWidget{
  @override
  AddOrEditPackState createState() =>AddOrEditPackState();
}

class AddOrEditPackState extends State<AddOrEditPack>{
  final formKey = GlobalKey<FormState>();
  String insuranceCategory = ' ';

  @override
  void initState() {
    getCategories();
  } …

我有一个下拉列表，其中填充了从 API 接收的对象。问题是当用户进行编辑时，我无法使用对象预先填充下拉列表。

以下是 JSON 示例：

[{"_id":"435463","userId":"3423423","username":"ma","categoryId":"5656756","insurerId":"567544","packageId":"5675","categoryName":"vehicle insurance","insurerName":"lic","packageName":"family"},      {"_id":"4564644","userId":"2342344","username":"ma","categoryId":"6575744","insurerId":"567567","packageId":"3455","categoryName":"life insurance","insurerName":"lic","packageName":"family"}]
``


    import 'package:flutter/material.dart';
    import 'package:http/http.dart' as http;
    import 'package:intl/intl.dart';
    import 'dart:convert';

    UserPackages selectedPckg;
    class AddOrEditClaim extends StatefulWidget {
      @override
      AddOrEditClaimState createState() => AddOrEditClaimState();
    }

    class AddOrEditClaimState extends State<AddOrEditClaim> {
      List<UserPackages> packageList = List();
      final formKey = GlobalKey<FormState>();

      @override
      void initState() {
            fetchPackages();
            selectedPckg= UserPackages();
            UserPackages packgToEdit = new UserPackages();
            packgToEdit.packageId="123";
            packgToEdit.packageName="family";
            selectedPckg=packgToEdit;

             super.initState();
      }

      @override
      Widget build(BuildContext context) {
        // TODO: implement build
        return new Scaffold(
            appBar: AppBar(
              title: Text('Add …