我的第一個 Flutter 應用程序構建中的文本字段問題

Question

我正在學習 flutter 並且我開發了我的第一個待辦事項應用程序。 我遇到的問題是該應用程序在我的設備和模擬器上的調試模式下運行良好，但是當我運行 flutter 運行構建命令並安裝發布 apk 時，您輸入 Todo 項的文本字段不起作用，而是我得到一個灰色框. 我會 append 一些圖像來澄清。 我是菜鳥，所以很可能我錯過了一些東西。 我只是想將我的應用程序作為發布 apk 進行測試，看看它是否流暢。

謝謝你的幫助！

這是 vscode 在我的摩托羅拉安裝的調試 apk

這就是該對話框在發布 apk 上的樣子

我已經上傳了項目供您查看，但這里是表單代碼和列表

TodoItemForm.dart：

import 'dart:ui';
import 'package:flutter/material.dart';
import 'package:todo/models/TodoItemModel.dart';

class TodoItemForm extends StatefulWidget {
  TodoItemForm({
    Key key,
    @required this.context,
    this.item,
    this.onSubmit,
    this.onClose,
  }) : super(key: key) {
    if (this.item == null)
      this.item = new TodoItemModel("", false, DateTime.now(), DateTime.now());
  }

  final BuildContext context;
  TodoItemModel item;
  final ValueChanged<TodoItemModel> onSubmit;
  final VoidCallback onClose;
  @override
  _TodoItemFormState createState() => _TodoItemFormState();
}

class _TodoItemFormState extends State<TodoItemForm> {
  TextEditingController _todoItemTextController = new TextEditingController();
  @override
  void initState() {
    super.initState();
    if (widget.item != null) {
      _todoItemTextController.value = TextEditingValue(text: widget.item.text);
    } else {
      widget.item = new TodoItemModel(
          _todoItemTextController.text, false, DateTime.now(), DateTime.now());
    }
  }

  void onSubmit() {
    widget.item.text = _todoItemTextController.text;
    widget.onSubmit(widget.item);
  }

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Row(
        children: <Widget>[
          Container(
            margin: EdgeInsets.fromLTRB(0, 0, 10, 0),
            child: Icon(
              Icons.playlist_add,
              color: Theme.of(context).primaryColor,
            ),
          ),
          Text(
            "New To Do Item",
          ),
        ],
      ),
      insetPadding: EdgeInsets.symmetric(horizontal: 2),
      content: Expanded(
        child: TextField(
          controller: _todoItemTextController,
          autofocus: true,
          decoration: InputDecoration(
            labelText: "Task to do:",
            hintText: "Buy Groseries!",
          ),
        ),
      ),
      actions: <Widget>[
        FlatButton(
          onPressed: this.onSubmit,
          child: Text(
            "SAVE",
            style: new TextStyle(color: Theme.of(context).accentColor),
          ),
        ),
        FlatButton(
          onPressed: widget.onClose,
          child: Text(
            "CANCEL",
            style: new TextStyle(color: Theme.of(context).accentColor),
          ),
        ),
      ],
    );
  }
}

任務列表.dart：

import 'dart:ui';

import 'package:flutter/material.dart';
import 'package:todo/models/TodoItemModel.dart';
import 'package:todo/services/TodoServiceProvider.dart';
import 'package:todo/widgets/TodoItem.dart';
import 'package:todo/widgets/TodoItemForm.dart';

class TaskList extends StatefulWidget {
  TaskList({Key key}) : super(key: key);

  @override
  _TaskListState createState() => _TaskListState();
}

class _TaskListState extends State<TaskList> {
  List<TodoItemModel> _items = [];
  final _todoItemTextController = new TextEditingController();

  @override
  void initState() {
    super.initState();
    this.refreshTodos();
  }

  void refreshTodos() {
    TodoServiceProvider.getTodoItems().then((todoList) {
      setState(() {
        _items = todoList;
      });
    });
  }

  void _handleSubmit(TodoItemModel newItem) {
    TodoServiceProvider.createTodo(newItem).then((todoItem) {
      this.refreshTodos();
      this._handleClose();
    });
  }

  void _handleEdit(TodoItemModel item) {
    TodoServiceProvider.updateTodo(item).then((todoItem) {
      this.refreshTodos();
      this._handleClose();
    });
  }

  void _handleClose() {
    Navigator.pop(context);
    _todoItemTextController.clear();
  }

  Future<bool> _handleItemCompleted(TodoItemModel model, DismissDirection dir) {
    return TodoServiceProvider.deleteTodo(model.id).then((response) {
      if (response) {
        setState(() {
          _items.remove(model);
        });
        return Future.value(true);
      }
      return Future.value(false);
    }).catchError((error) => Future.value(false));
  }

  void _showTodoItemForm({TodoItemModel item: null}) {
    final alert = TodoItemForm(
      context: context,
      item: item,
      onSubmit: item == null ? this._handleSubmit : this._handleEdit,
      onClose: this._handleClose,
    );

    showDialog(
      context: context,
      builder: (_) {
        return alert;
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Todo"),
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.add),
        onPressed: _showTodoItemForm,
      ),
      body: Container(
        padding: EdgeInsets.all(12),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.start,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Expanded(
              child: ReorderableListView(
                onReorder: (oldIndex, newIndex) {
                  this.setState(() {
                    final aux = _items[oldIndex];
                    if (oldIndex > newIndex) {
                      _items.removeAt(oldIndex);
                      _items.insert(newIndex, aux);
                    } else {
                      _items.insert(newIndex, aux);
                      _items.removeAt(oldIndex);
                    }
                  });
                },
                children: [
                  for (final _item in _items)
                    FlatButton(
                      key: ValueKey(_item),
                      child: TodoItem(
                        model: _item,
                        onItemCompleted: this._handleItemCompleted,
                      ),
                      onPressed: () {
                        this._showTodoItemForm(item: _item);
                      },
                    ),
                ],
              ),
            )
          ],
        ),
      ),
    );
  }
}

TodoItemModel.dart：

import 'package:todo/widgets/TodoItem.dart';

class TodoItemModel {
  int _id;
  String _text;
  bool _finished;
  DateTime _creationDate;
  DateTime _dueDate;

  TodoItemModel(this._text, this._finished, this._creationDate, this._dueDate);

  int get id => _id;
  String get text => _text;
  DateTime get creationDate => _creationDate;

  void set text(String value) {
    _text = value;
  }

  void set id(int value) => _id = value;

      
  Map<String, dynamic> toJSON() {
    var map = new Map<String, dynamic>();
    map["text"] = _text;
    map["creation_date"] = _creationDate.toIso8601String();
    if (_id != null) map["id"] = _id;

    return map;
  }

  TodoItemModel.fromJSON(Map<String, dynamic> json) {
    this._id = json["id"];
    this._text = json["text"];
    this._creationDate = DateTime.parse(json["creation_date"]);
  }
}

完整項目 url: https://drive.google.com/drive/folders/1tNue3EfdwV_7M7zHt_A7A4RsNIdppHqj?usp=sharing

Answer 1

我認為問題在於 AlertDialog 中的擴展小部件。

TodoItemForm.dart：

import 'dart:ui';
import 'package:flutter/material.dart';
import 'package:todo/models/TodoItemModel.dart';

class TodoItemForm extends StatefulWidget {
  TodoItemForm({
    Key key,
    @required this.context,
    this.item,
    this.onSubmit,
    this.onClose,
  }) : super(key: key) {
    if (this.item == null)
      this.item = new TodoItemModel("", false, DateTime.now(), DateTime.now());
  }

  final BuildContext context;
  TodoItemModel item;
  final ValueChanged<TodoItemModel> onSubmit;
  final VoidCallback onClose;
  @override
  _TodoItemFormState createState() => _TodoItemFormState();
}

class _TodoItemFormState extends State<TodoItemForm> {
  TextEditingController _todoItemTextController = new TextEditingController();
  @override
  void initState() {
    super.initState();
    if (widget.item != null) {
      _todoItemTextController.value = TextEditingValue(text: widget.item.text);
    } else {
      widget.item = new TodoItemModel(
          _todoItemTextController.text, false, DateTime.now(), DateTime.now());
    }
  }

  void onSubmit() {
    widget.item.text = _todoItemTextController.text;
    widget.onSubmit(widget.item);
  }

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Row(
        children: <Widget>[
          Container(
            margin: EdgeInsets.fromLTRB(0, 0, 10, 0),
            child: Icon(
              Icons.playlist_add,
              color: Theme.of(context).primaryColor,
            ),
          ),
          Text(
            "New To Do Item",
          ),
        ],
      ),
      insetPadding: EdgeInsets.symmetric(horizontal: 2),
      content: Container( //Change this line
        child: TextField(
          controller: _todoItemTextController,
          autofocus: true,
          decoration: InputDecoration(
            labelText: "Task to do:",
            hintText: "Buy Groseries!",
          ),
        ),
      ),
      actions: <Widget>[
        FlatButton(
          onPressed: this.onSubmit,
          child: Text(
            "SAVE",
            style: new TextStyle(color: Theme.of(context).accentColor),
          ),
        ),
        FlatButton(
          onPressed: widget.onClose,
          child: Text(
            "CANCEL",
            style: new TextStyle(color: Theme.of(context).accentColor),
          ),
        ),
      ],
    );
  }
}