如何从 Flutter 中 TextField 的 buildTextField(a Extracted Widget) 中获取值答案

【问题标题】：How to get a value from the buildTextField(a Extracted Widget) of TextField in flutter如何从 Flutter 中 TextField 的 buildTextField(a Extracted Widget) 中获取值
【发布时间】：2021-09-15 04:09:48
【问题描述】：

我提取了一个小部件并在代码中多次使用它我在从每个文本字段中获取值时卡住了

我的自定义函数代码是这样的：

  Widget buildTextField(
      IconData icon, String hintText, bool isEmail, dynamic _valueoffield) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8.0),
      child: TextField(
        obscureText: hintText == "Password" ? _isHidden : false,
        keyboardType: isEmail ? TextInputType.emailAddress : TextInputType.text,
        onSubmitted: (_valueoffield) {},
        decoration: InputDecoration(
            prefixIcon: Icon(
              icon,
              color: Palette.iconColor,
            ),
            enabledBorder: OutlineInputBorder(
              borderSide: BorderSide(color: Palette.textColor1),
              borderRadius: BorderRadius.all(Radius.circular(35.0)),
            ),
            focusedBorder: OutlineInputBorder(
              borderSide: BorderSide(color: Palette.textColor1),
              borderRadius: BorderRadius.all(Radius.circular(35.0)),
            ),
            contentPadding: EdgeInsets.all(10),
            hintText: hintText,
            hintStyle: TextStyle(fontSize: 14, color: Palette.textColor1),
            suffixIcon: hintText == 'Password'
                ? IconButton(
                    onPressed: _toggleVisibility,
                    icon: _isHidden
                        ? Icon(Icons.visibility_off_outlined)
                        : Icon(Icons.visibility_outlined))
                : null),
      ),
    );
  }

【问题讨论】：

标签： flutter

【解决方案1】：

对 TextField 使用控制器总是更好，所以不要像 _valueoffield 那样传递 TextEditingController：

  TextEditingController usernameController = TextEditingController();
  TextEditingController passwordController = TextEditingController();
  ...
  buildTextField(
    ....
    usernameController,
  )
  buildTextField(
    ....
    passwordController,
  )

并得到这样的值

String username;
...
username = usernameController.text;

所以函数会是

  Widget buildTextField(
      IconData icon, String hintText, bool isEmail, TextEditingController controller) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8.0),
      child: TextField(
        obscureText: hintText == "Password" ? _isHidden : false,
        keyboardType: isEmail ? TextInputType.emailAddress : TextInputType.text,
        controller: controller,
        decoration: InputDecoration(
            prefixIcon: Icon(
              icon,
              color: Palette.iconColor,
            ),
            enabledBorder: OutlineInputBorder(
              borderSide: BorderSide(color: Palette.textColor1),
              borderRadius: BorderRadius.all(Radius.circular(35.0)),
            ),
            focusedBorder: OutlineInputBorder(
              borderSide: BorderSide(color: Palette.textColor1),
              borderRadius: BorderRadius.all(Radius.circular(35.0)),
            ),
            contentPadding: EdgeInsets.all(10),
            hintText: hintText,
            hintStyle: TextStyle(fontSize: 14, color: Palette.textColor1),
            suffixIcon: hintText == 'Password'
                ? IconButton(
                    onPressed: _toggleVisibility,
                    icon: _isHidden
                        ? Icon(Icons.visibility_off_outlined)
                        : Icon(Icons.visibility_outlined))
                : null),
      ),
    );
  }

我强烈建议在输入字段中使用 Form 和 TextFormField

【讨论】：