flutter-TextField/TextFromField---suffixIcon点击时不弹出键盘

import 'dart:async';

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, required this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {

  bool _isHidePassWord = false;
  FocusNode _focusNode = FocusNode();
  TextEditingController _pwdController = TextEditingController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            TextFormField(
              controller: _pwdController,
              focusNode: _focusNode,
              decoration: InputDecoration(
                icon: Icon(Icons.lock),
                labelText: '密码：',
                hintText: '请输入密码',
                hintStyle: TextStyle(fontSize: 12),
                suffixIcon: IconButton(
                  onPressed: () {
                    //判断TextFormField是否处于获得焦点的状态，如果没有，当点击图标时禁止TextFormField获取焦点，也就不会弹出软键盘了，当TextFormField获取焦点时，点击图标，不关闭软键盘
                    if (!_focusNode.hasFocus) {
                      _focusNode.canRequestFocus = false;
                      Future.delayed(Duration(milliseconds: 500), () {
                        _focusNode.canRequestFocus = true;
                      });
                    }
                    setState(() {
                      print(_isHidePassWord);
                      _isHidePassWord = !_isHidePassWord;
                    });
                  },
                  icon: Icon(_isHidePassWord
                      ? Icons.visibility_off
                      : Icons.visibility),
                ),
              ),
              validator: (v) => v!.trim().length >= 6 ? null : '密码最多六位',
              obscureText: _isHidePassWord,
              textInputAction: TextInputAction.done, //设置软键盘确定按键显示为完成
            )
          ],
        ),
      ),
    );
  }
}