总之，这是Flutter 1.17的工作解决方案:

像这样包装你的Widget:

GestureDetector(
        onTap: FocusScope.of(context).unfocus,
        child: YourWidget(),
);

你可以用这个。

FocusScope或(上下文)。requestFocus (FocusNode ());

你可以使用这个手势侦测器的onTap或者像这样的InkWell。

“GestureDetector ( onTap:() {' //这个焦点范围将关闭键盘 FocusScope.of(上下文).requestFocus (FocusNode ()); forgotPasswordAPI (emailController.text); }”、“

在构建小部件中添加此代码

    FocusScope.of(context).requestFocus(FocusNode());

您可以使用FocusNode类中的unfocus()方法。

import 'package:flutter/material.dart';

class MyHomePage extends StatefulWidget {
  MyHomePageState createState() => new MyHomePageState();
}

class MyHomePageState extends State<MyHomePage> {
  TextEditingController _controller = new TextEditingController();
  FocusNode _focusNode = new FocusNode(); //1 - declare and initialize variable

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(),
      floatingActionButton: new FloatingActionButton(
        child: new Icon(Icons.send),
        onPressed: () {
            _focusNode.unfocus(); //3 - call this method here
        },
      ),
      body: new Container(
        alignment: FractionalOffset.center,
        padding: new EdgeInsets.all(20.0),
        child: new TextFormField(
          controller: _controller,
          focusNode: _focusNode, //2 - assign it to your TextFormField
          decoration: new InputDecoration(labelText: 'Example Text'),
        ),
      ),
    );
  }
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      home: new MyHomePage(),
    );
  }
}

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

使用FocusScope的解决方案不适合我。 我又找到了一个:

import 'package:flutter/services.dart';

SystemChannels.textInput.invokeMethod('TextInput.hide');

它解决了我的问题。

下面的代码帮助我隐藏键盘

   void initState() {
   SystemChannels.textInput.invokeMethod('TextInput.hide');
   super.initState();
   }