added keyboard input

lib/main.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 
 void main() {
   runApp(const MyApp());
@@ -51,7 +52,14 @@ class _MyHomePageState extends State<MyHomePage> {
         backgroundColor: Theme.of(context).colorScheme.inversePrimary,
         title: Text(widget.title),
       ),
-      body: Center(
+      body: RawKeyboardListener(
+        focusNode: FocusNode(),
+        autofocus: true,
+        onKey: (RawKeyEvent event) {
+          if (event.isKeyPressed(LogicalKeyboardKey.keyD)) _decrementCounter();
+          if (event.isKeyPressed(LogicalKeyboardKey.keyI)) _incrementCounter();
+        },
+        child: Center(
           child: Column(
             mainAxisAlignment: MainAxisAlignment.center,
             children: <Widget>[
@@ -65,10 +73,11 @@ class _MyHomePageState extends State<MyHomePage> {
             ],
           ),
         ),
+      ),
       floatingActionButton: Stack(
         children: <Widget>[
           Padding(
-            padding: EdgeInsets.only(left: 31),
+            padding: const EdgeInsets.only(left: 31),
             child: Align(
               alignment: Alignment.bottomLeft,
               child: FloatingActionButton(