Add log out button

lib/home_page.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:logging/logging.dart';
+import 'package:sheetless/login_page.dart';
 import 'package:sheetless/sheet_viewer_page.dart';
 import 'package:sheetless/storage_helper.dart';
 
@@ -60,10 +61,30 @@ class _MyHomePageState extends State<MyHomePage> {
     return sheets;
   }
 
+  Future<void> _logOut() async {
+    // Delete saved jwt
+    await _storageHelper.writeSecure(SecureStorageKey.jwt, null);
+
+    if (!mounted) return; // Widget already removed
+
+    Navigator.of(
+      context,
+    ).pushReplacement(MaterialPageRoute(builder: (_) => LoginPage()));
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
-      appBar: AppBar(title: const Text("My Sheets")),
+      appBar: AppBar(
+        title: const Text("Sheetless"),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.logout),
+            tooltip: 'Logout',
+            onPressed: _logOut,
+          ),
+        ],
+      ),
       body: FutureBuilder(
         future: acquireSheets(),
         builder: (BuildContext context, AsyncSnapshot<List<Sheet>> snapshot) {

lib/storage_helper.dart

@@ -31,7 +31,7 @@ class StorageHelper {
     return secureStorage.read(key: key.name);
   }
 
-  Future<void> writeSecure(SecureStorageKey key, String value) {
+  Future<void> writeSecure(SecureStorageKey key, String? value) {
     return secureStorage.write(key: key.name, value: value);
   }