update react

src/app/message-banner.tsx

@@ -0,0 +1,18 @@
+import {actionClosedMessageBanner} from "./state/action.ts";
+import styles from "./message-banner.module.css";
+
+export default function MessageBanner({state, dispatch}) {
+    function handleClose() {
+        dispatch(actionClosedMessageBanner());
+    }
+
+    if (!!state.errorMessage) {
+        return (
+            <div className={styles.banner + " " + styles.message}>
+                {state.errorMessage}
+                <button onClick={handleClose}>Dismiss message</button>
+            </div>
+        );
+    }
+    return (<div className={styles.banner + " " + styles.empty}></div>);
+}