feat: add logout button

ui/lib/main.dart

@@ -1,7 +1,7 @@
-import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:ui/activity.dart';
 import 'package:ui/login_page.dart';
 import 'package:ui/navdrawer.dart';
@@ -48,7 +48,17 @@ class MyApp extends StatelessWidget {
                 actions: [
                   IconButton(
                       onPressed: () => context.go(SystemSettingsPage.route),
-                      icon: const Icon(Icons.settings))
+                      icon: const Icon(Icons.settings)),
+                  APIs.isLoggedIn
+                      ? IconButton(
+                          onPressed: () async {
+                            final SharedPreferences prefs =
+                                await SharedPreferences.getInstance();
+                            await prefs.remove('token');
+                            context.go(LoginScreen.route);
+                          },
+                          icon: const Icon(Icons.exit_to_app))
+                      : Container()
                 ],
               ),
               body: Center(
@@ -106,21 +116,6 @@ class MyApp extends StatelessWidget {
       child: MaterialApp.router(
         title: 'Polaris',
         theme: ThemeData(
-          // This is the theme of your application.
-          //
-          // TRY THIS: Try running your application with "flutter run". You'll see
-          // the application has a purple toolbar. Then, without quitting the app,
-          // try changing the seedColor in the colorScheme below to Colors.green
-          // and then invoke "hot reload" (save your changes or press the "hot
-          // reload" button in a Flutter-supported IDE, or press "r" if you used
-          // the command line to start the app).
-          //
-          // Notice that the counter didn't reset back to zero; the application
-          // state is not lost during the reload. To reset the state, use hot
-          // restart instead.
-          //
-          // This works for code too, not just values: Most code changes can be
-          // tested with just a hot reload.
           colorScheme: ColorScheme.fromSeed(
               seedColor: Colors.blue, brightness: Brightness.dark),
           useMaterial3: true,

ui/lib/navdrawer.dart

@@ -1,7 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
 import 'package:ui/activity.dart';
-import 'package:ui/search.dart';
 import 'package:ui/system_settings.dart';
 import 'package:ui/weclome.dart';
 

ui/lib/providers/APIs.dart

@@ -2,6 +2,7 @@ import 'package:dio/dio.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
+import 'package:quiver/strings.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 class APIs {
@@ -40,6 +41,7 @@ class APIs {
 
   static Dio? dio1;
   static Map<String, String> authHeaders = {};
+  static bool isLoggedIn = false;
 
   static Future<Dio> getDio() async {
     if (dio1 != null) {
@@ -47,8 +49,10 @@ class APIs {
     }
     final SharedPreferences prefs = await SharedPreferences.getInstance();
     var token = prefs.getString("token");
-
+    if (isNotBlank(token)) {
-    authHeaders["Authorization"] = "Bearer $token";
+      authHeaders["Authorization"] = "Bearer $token";
+      isLoggedIn = true;
+    }
 
     var dio = Dio();
     dio.interceptors.add(InterceptorsWrapper(