dart - 在 TextInputType 更改后 Controller 重置的 Flutter TextField

Question

我在我的应用程序中使用全屏对话框将用户输入值输入到文本字段中。其中一些值是字符串，一些是整数。所以我想相应地更改键盘以使不必要的键消失。这是我的实现:

import 'package:flutter/material.dart';
import 'package:meal_tracker/model/food_model.dart';

class AddFoodDialog extends StatelessWidget {
  TextEditingController nameController = TextEditingController(),
      carbsController = TextEditingController(),
      fatController = TextEditingController(),
      proteinController = TextEditingController(),
      amountController = TextEditingController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Add Food"),
        actions: <Widget>[
          FlatButton(
            child: Text(
              "SAVE",
              style: TextStyle(color: Colors.white),
            ),
            onPressed: () {
              _handleSave(context);
            },
          )
        ],
      ),
      body: Form(
          child: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          children: <Widget>[
            TextFormField(
              decoration: InputDecoration(labelText: "Name"),
              controller: nameController,
            ),
            TextFormField(
              decoration: InputDecoration(labelText: "Carbs per 100g"),
              controller: carbsController,
              keyboardType: TextInputType.number,
            ),
            TextFormField(
              decoration: InputDecoration(labelText: "Fat per 100g"),
              controller: fatController,
              keyboardType: TextInputType.number,
            ),
            TextFormField(
              decoration: InputDecoration(labelText: "Protein per 100g"),
              controller: proteinController,
              keyboardType: TextInputType.number,
            ),
            TextFormField(
              decoration: InputDecoration(labelText: "Amount in g"),
              controller: amountController,
              keyboardType: TextInputType.number,
            ),
          ],
        ),
      )),
    );
  }

  void _handleSave(BuildContext context) {
    print("Dialog text: " + nameController.text);
    Navigator.of(context).pop(Food(
        name: nameController.text,
        carbsPer100g: double.parse(carbsController.text),
        fatPer100g: double.parse(fatController.text),
        proteinPer100g: double.parse(proteinController.text),
        amount: double.parse(amountController.text)));
  }
}

问题是，当我在具有 TextInputType.text 的“名称”TextField 中输入内容，然后点击另一个具有 TextInputType.number，“名称”字段无缘无故清除。反过来也一样。

Answer 1

我不得不将 TextEditingControllers 放在一个有状态的小部件中，这确实有效。感谢 Jonah Williams 的快速回复!