3 files changed, 36 insertions, 58 deletions
diff --git a/lib/data.dart b/lib/data.dart
index f2e3531..5cd59ec 100644
--- a/lib/data.dart
+++ b/lib/data.dart
@@ -1,3 +1,14 @@
+import 'package:flutter/foundation.dart';
+
+class AppState with ChangeNotifier {
+    List<Contact> contacts = <Contact>[
+      Contact(address: "Living Room Window", isOpen: false),
+      Contact(address: "Front Door", isOpen: true),
+      Contact(address: "Back Door", isOpen: false),
+      Contact(address: "Garage Window", isOpen: true),
+    ];
+}
+
 class Contact {
   final String address;
   bool isOpen;
diff --git a/lib/main.dart b/lib/main.dart
index 805ef69..1601965 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -1,7 +1,14 @@
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 
 import 'ui.dart';
+import 'data.dart';
 
 void main() {
-  runApp(const UI());
+  runApp(
+    ChangeNotifierProvider<AppState>(
+      create: (BuildContext context) => AppState(),
+      child: const UI(),
+    ),
+  );
 }
diff --git a/lib/ui.dart b/lib/ui.dart
index 5397044..d4618cf 100644
--- a/lib/ui.dart
+++ b/lib/ui.dart
@@ -1,6 +1,5 @@
-import 'dart:async';
-
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 
 import 'data.dart';
 
@@ -15,69 +14,30 @@ class UI extends StatelessWidget {
   }
 }
 
-class ContactList extends StatefulWidget {
+class ContactList extends StatelessWidget {
   const ContactList({super.key});
 
   @override
-  State<ContactList> createState() => _ContactListState();
-}
-
-class _ContactListState extends State<ContactList> {
-  late final List<Contact> contacts;
-  Timer? _timer;
-
-  @override
-  void initState() {
-    super.initState();
-
-    contacts = <Contact>[
-      Contact(address: "Living Room Window", isOpen: false),
-      Contact(address: "Front Door", isOpen: true),
-      Contact(address: "Back Door", isOpen: false),
-      Contact(address: "Garage Window", isOpen: true),
-    ];
-
-    _timer = Timer.periodic(const Duration(seconds: 1), (_) {
-      setState(() {
-        contacts[0].isOpen = !contacts[0].isOpen;
-      });
-    });
-  }
-
-  @override
-  void dispose() {
-    _timer?.cancel();
-    super.dispose();
-  }
-
-  @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(title: const Text("Contacts")),
-      body: ListView.builder(
-        itemCount: contacts.length,
-        itemBuilder: (BuildContext context, int index) {
-          final Contact contact = contacts[index];
-          return ContactTile(contact: contact);
+      body: Consumer<AppState>(
+        builder: (BuildContext context, AppState state, Widget? child) {
+          return ListView.builder(
+            itemCount: state.contacts.length,
+            itemBuilder: (BuildContext context, int index) {
+              final Contact contact = state.contacts[index];
+              return ListTile(
+                leading: Icon(
+                  contact.isOpen ? Icons.meeting_room : Icons.door_front_door,
+                  color: contact.isOpen ? Colors.red : Colors.green,
+                ),
+                title: Text(contact.address),
+              );
+            },
+          );
         },
       ),
     );
   }
 }
-
-class ContactTile extends StatelessWidget {
-  final Contact contact;
-
-  const ContactTile({super.key, required this.contact});
-
-  @override
-  Widget build(BuildContext context) {
-    return ListTile(
-      leading: Icon(
-        contact.isOpen ? Icons.meeting_room : Icons.door_front_door,
-        color: contact.isOpen ? Colors.red : Colors.green,
-      ),
-      title: Text(contact.address),
-    );
-  }
-}