make App() class

src/ui/App.tsx

@@ -11,6 +11,14 @@ import ServerLaunchSection from './components/ServerLaunchSection'
 import ProgressBar from './components/common/ProgressBar'
 import MainProgressBar from './components/common/MainProgressBar'
 
+interface IProps {
+  [key: string]: never
+}
+
+interface IState {
+  isDownloading: boolean
+}
+
 const downloadHandler = new DownloadHandler()
 
 async function download(url: string, filename: string, path: string) {
@@ -26,20 +34,29 @@ async function TESTDOWNLOAD() {
   )
 }
 
-function App() {
-  return (
-    <div className="App">
-      <Topbar />
+class App extends React.Component<IProps, IState> {
+  constructor(props: IProps) {
+    super(props)
+    this.state = {
+      isDownloading: false,
+    }
+  }
 
-      <button onClick={TESTDOWNLOAD}>download file test</button>
+  render() {
+    return (
+      <div className="App">
+        <Topbar />
 
-      <ServerLaunchSection />
+        <button onClick={TESTDOWNLOAD}>download file test</button>
 
-      <div id="DownloadProgress">
-        <MainProgressBar downloadManager={downloadHandler} />
+        <ServerLaunchSection />
+
+        <div id="DownloadProgress">
+          <MainProgressBar downloadManager={downloadHandler} />
+        </div>
       </div>
-    </div>
-  )
+    )
+  }
 }
 
 export default App