diff --git a/src/App.tsx b/src/App.tsx
index f819cbdb9..f69f96d46 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,7 +1,35 @@
import React from 'react';
-export const App: React.FC = () => (
-
-
The last pressed key is [Enter]
-
-);
+type State = {
+ key: string;
+};
+
+export class App extends React.Component<{}, State> {
+ state: State = { key: '' };
+
+ keyupHandler = (event: KeyboardEvent) => {
+ this.setState({ key: event.key });
+ };
+
+ componentDidMount() {
+ document.addEventListener('keyup', this.keyupHandler);
+ }
+
+ componentWillUnmount() {
+ document.removeEventListener('keyup', this.keyupHandler);
+ }
+
+ render() {
+ return (
+
+ {this.state.key.length ? (
+
+ The last pressed key is [{this.state.key}]
+
+ ) : (
+
Nothing was pressed yet
+ )}
+
+ );
+ }
+}