How to show and hide/dismiss keyboard

If you don’t want to go through step by step, you can use below method to save time:

/// Hide the soft keyboard.
void hideKeyboard(BuildContext context) {
FocusScope.of(context).requestFocus(FocusNode());
}

Declare and create new FocusNode

class _DismissKeyboardTutorialScreenState extends State<DismissKeyboardTutorialScreen> {
  FocusNode focusNode;

  @override
  void initState() {
    super.initState();

    focusNode = FocusNode();
  }
  // ...
}

“Connect” your TextField with above focusNode

@override
Widget build(BuildContext context) {
  // ... Other widgets
  TextField(
    focusNode: focusNode,
  ),
  // ... Other widgets
}

Create showKeyboard() and dismissKeyboard() methods

void showKeyboard() {
  focusNode.requestFocus();
}

void dismissKeyboard() {
  focusNode.unfocus();
}

Use those methods

RaisedButton(
  onPressed: () {
    showKeyboard();
  },
  child: Text('Show Keyboard'),
),          
RaisedButton(
  onPressed: () {
    dismissKeyboard();
  },
  child: Text('Dismiss Keyboard'),
),

Don’t forget to dispose the FocusNode

@override
void dispose() {
  focusNode.dispose();

  super.dispose();
}

Put it all together

import 'package:flutter/material.dart';

void main() => runApp(ShowSnackBarDemo());

class ShowSnackBarDemo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Coflutter - Dismiss Keyboard',
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Coflutter - Dismiss Keyboard'),
          backgroundColor: const Color(0xffae00f0),
        ),
        body: DismissKeyboardTutorialScreen(),
      ),
    );
  }
}

class DismissKeyboardTutorialScreen extends StatefulWidget {
  @override
  _DismissKeyboardTutorialScreenState createState() =>
      _DismissKeyboardTutorialScreenState();
}

class _DismissKeyboardTutorialScreenState
    extends State<DismissKeyboardTutorialScreen> {
  FocusNode focusNode;

  @override
  void initState() {
    super.initState();

    focusNode = FocusNode();
    focusNode.addListener(() {
      print('Listener');
    });
  }

  @override
  void dispose() {
    focusNode.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Padding(
            padding: const EdgeInsets.all(10.0),
            child: TextField(
              autofocus: true,
              focusNode: focusNode,
            ),
          ),
          RaisedButton(
            onPressed: () {
              showKeyboard();
            },
            child: Text('Show Keyboard'),
          ),
          RaisedButton(
            onPressed: () {
              dismissKeyboard();
            },
            child: Text('Dismiss Keyboard'),
          ),
        ],
      ),
    );
  }

  void showKeyboard() {
    focusNode.requestFocus();
  }

  void dismissKeyboard() {
    focusNode.unfocus();
  }
}

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