Flutter Web中iPhone/iPad点击TextField时Dialog自动关闭问题求助

在Flutter Web环境下，实现了一个包含登录表单的AlertDialog，但在iPhone或iPad上点击其中的TextField唤起键盘时，Dialog会自动关闭。该问题在iOS或Android原生Flutter应用中并未出现。曾怀疑是控制器导致组件重建，但移除控制器后问题依然存在，使用Modal时也有类似问题。

相关代码如下：

showDialog(
  context: context,
  barrierDismissible: false,
  builder: (BuildContext context) {
    return AlertDialog(
      title: const Text('AlertDialog Title'),
      content: SingleChildScrollView(
        child: ListBody(
          children: <Widget>[
            TextFormField(
              autofocus: true,
              decoration: InputDecoration(
                hintText: 'Email',
                hintStyle: TextStyle(fontSize: 14),
                prefixIcon: Icon(Icons.email),
                contentPadding: EdgeInsets.symmetric(horizontal: 10, vertical: 12),
                border: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(14),
                  borderSide: BorderSide(width: 1, style: BorderStyle.solid),
                ),
                filled: true,
                fillColor: colorInputField,
                enabledBorder: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(14),
                  borderSide: BorderSide(
                    color: colorBackgroundSecondary,
                    width: 1,
                  ),
                ),
                focusedBorder: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(14),
                  borderSide: BorderSide(
                    color: colorPrimary,
                    width: 1,
                  ),
                ),
              ),
              keyboardType: TextInputType.emailAddress,
              validator: (value) {
                if (value == null || value.isEmpty || !value.contains('@')) {
                  return 'Please enter a valid email address';
                }
                return null;
              },
              controller: emailController,
            ),
          ],
        ),
      ),
      actions: <Widget>[
        TextButton(
          child: const Text('Approve'),
          onPressed: () {
            Navigator.of(context).pop();
          },
        ),
      ],
    );
  },
);

内容的提问来源于stack exchange，提问作者Volodymyr Lekhman