Add firebase support to web_dashboard (#421)

* add mock data, app state, model classes

* Set up app without ChangeNotifier

* refactor

* add experiments to experimental/

* Add project-agnostic Firebase authentication code

* add sign in button

* add stub firebase API

* add firestore

* refactor code for google_sign_in

* update pubspec.lock

* switch to mocks for non-firebase version

* Add firebase instructions to the README

* fix README

* sign in silently if the user is already signed in

* add json_serializable

* update README

* ignore 'id' field on types

* Implement FirebaseItemApi

* Add build_runner instructions to README

* remove experiments directory

* add EditItemForm

* move types.dart into api.dart

* move mock and firebase configuration into the constructor

* add main_mock entrypoint

* add copyright checks to grinder script

* fix fix-copyright task

* run grind fix-copyright

* add run and generate tasks

* add run tasks to grind script

* add fillWithMockData() fix delete() in mock API

* add edit / new form dialogs

* Add charts that display entries from Firebase

* Add Entries list without editing

* refactor home page

* format

* Add entries page functionality

* Show current day in charts

* cleanup: pubspec.lock, remove type annotation

* Remove _selectedItem from Home page

Add ItemsDropdown
Use ItemsDropdown in NewEntryDialog / NewEntryForm

* rename item-category

* don't wait to show snackbar on delete

* fix circular progress indicator

* Move dialogs into dialogs.dart

* run grind fix-copyright

* remove unused import

* Refactor entry total calculation, add chart_utils library

* fix bug in chart_utils.dart

* convert CategoryChart to a stateless widget

* use a const for number of days in chart

* code review updates

- rename stream -> subscribe
- timeStamp -> timestamp
- remove latest() from API
- use FutureBuilder and StreamBuilder instead of stateful widget
- rename variables in mock_service_test.dart

* use a single collection reference in firebase API

* remove reference to stream in mock API

* Use a new type,  _EntriesEvent to improve filtering in mock API

* add analysis_options.yaml and fix (most) issues

* fix avoid_types_on_closure_parameters lint warnings

* use spread operator in dashboard.dart

* handle case where selected item in the category dropdown goes away

* use StreamBuilder + FutureBuilder on Entries page

* rename method

* use fake firebase configuration

* update pubspec.lock

* update README

* Change categories_dropdown to FutureBuilder + StreamBuilder

* Update minSdkVersion in build.gradle

SDK version 16 was failing: "The number of method references in a .dex
file cannot exceed 64K."

* update README

* Use a collection reference in FirebaseEntryApi

Already added to FirebaseCategoryApi

* Invoke onSelected in CategoriesDropdown when necessary

Also, avoid calling onSelected during a build.

* fix misnamed var

* remove unused import

* Use relative imports

* Use extension methods for DateTime utilities

* remove forms.dart

* Make Firebase instructions specific for this sample

* add copyright headers

* fix grammar

* dartfmt

* avoid setState() during build phase in CategoryDropdown

* add empty test to material_theme_builder

experimental/web_dashboard/lib/src/api/api.dart

@@ -2,44 +2,106 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:json_annotation/json_annotation.dart';
+
+part 'api.g.dart';
+
 /// Manipulates app data,
 abstract class DashboardApi {
-  ItemApi get items;
+  CategoryApi get categories;
   EntryApi get entries;
 }
 
-/// Manipulates [Item] data.
-abstract class ItemApi {
-  Future<Item> delete(String id);
-  Future<Item> get(String id);
-  Future<Item> insert(Item item);
-  Future<List<Item>> list();
-  Future<Item> update(Item item, String id);
-  Stream<List<Item>> allItemsStream();
-}
+/// Manipulates [Category] data.
+abstract class CategoryApi {
+  Future<Category> delete(String id);
 
-/// Something being tracked.
-class Item {
-  final String name;
-  String id;
+  Future<Category> get(String id);
 
-  Item(this.name);
+  Future<Category> insert(Category category);
+
+  Future<List<Category>> list();
+
+  Future<Category> update(Category category, String id);
+
+  Stream<List<Category>> subscribe();
 }
 
 /// Manipulates [Entry] data.
 abstract class EntryApi {
-  Future<Entry> delete(String itemId, String id);
-  Future<Entry> insert(String itemId, Entry entry);
-  Future<List<Entry>> list(String itemId);
-  Future<Entry> update(String itemId, String id, Entry entry);
-  Stream<List<Entry>> allEntriesStream(String itemId);
+  Future<Entry> delete(String categoryId, String id);
+
+  Future<Entry> get(String categoryId, String id);
+
+  Future<Entry> insert(String categoryId, Entry entry);
+
+  Future<List<Entry>> list(String categoryId);
+
+  Future<Entry> update(String categoryId, String id, Entry entry);
+
+  Stream<List<Entry>> subscribe(String categoryId);
+}
+
+/// Something that's being tracked, e.g. Hours Slept, Cups of water, etc.
+@JsonSerializable()
+class Category {
+  String name;
+
+  @JsonKey(ignore: true)
+  String id;
+
+  Category(this.name);
+
+  factory Category.fromJson(Map<String, dynamic> json) =>
+      _$CategoryFromJson(json);
+
+  Map<String, dynamic> toJson() => _$CategoryToJson(this);
+
+  @override
+  operator ==(Object other) => other is Category && other.id == id;
+  @override
+  int get hashCode => id.hashCode;
+  @override
+  String toString() {
+    return '<Category id=$id>';
+  }
 }
 
 /// A number tracked at a point in time.
+@JsonSerializable()
 class Entry {
-  final int value;
-  final DateTime time;
+  int value;
+  @JsonKey(fromJson: _timestampToDateTime, toJson: _dateTimeToTimestamp)
+  DateTime time;
+
+  @JsonKey(ignore: true)
   String id;
 
   Entry(this.value, this.time);
+
+  factory Entry.fromJson(Map<String, dynamic> json) => _$EntryFromJson(json);
+
+  Map<String, dynamic> toJson() => _$EntryToJson(this);
+
+  static DateTime _timestampToDateTime(Timestamp timestamp) {
+    return DateTime.fromMillisecondsSinceEpoch(
+        timestamp.millisecondsSinceEpoch);
+  }
+
+  static Timestamp _dateTimeToTimestamp(DateTime dateTime) {
+    return Timestamp.fromMillisecondsSinceEpoch(
+        dateTime.millisecondsSinceEpoch);
+  }
+
+  @override
+  operator ==(Object other) => other is Entry && other.id == id;
+
+  @override
+  int get hashCode => id.hashCode;
+
+  @override
+  String toString() {
+    return '<Entry id=$id>';
+  }
 }

experimental/web_dashboard/lib/src/api/api.g.dart

@@ -0,0 +1,33 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'api.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+Category _$CategoryFromJson(Map<String, dynamic> json) {
+  return Category(
+    json['name'] as String,
+  );
+}
+
+Map<String, dynamic> _$CategoryToJson(Category instance) => <String, dynamic>{
+      'name': instance.name,
+    };
+
+Entry _$EntryFromJson(Map<String, dynamic> json) {
+  return Entry(
+    json['value'] as int,
+    Entry._timestampToDateTime(json['time'] as Timestamp),
+  );
+}
+
+Map<String, dynamic> _$EntryToJson(Entry instance) => <String, dynamic>{
+      'value': instance.value,
+      'time': Entry._dateTimeToTimestamp(instance.time),
+    };

experimental/web_dashboard/lib/src/api/firebase.dart

@@ -1,3 +1,151 @@
 // Copyright 2020, the Flutter project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
+
+import 'package:cloud_firestore/cloud_firestore.dart';
+
+import 'api.dart';
+
+class FirebaseDashboardApi implements DashboardApi {
+  @override
+  final EntryApi entries;
+
+  @override
+  final CategoryApi categories;
+
+  FirebaseDashboardApi(Firestore firestore, String userId)
+      : entries = FirebaseEntryApi(firestore, userId),
+        categories = FirebaseCategoryApi(firestore, userId);
+}
+
+class FirebaseEntryApi implements EntryApi {
+  final Firestore firestore;
+  final String userId;
+  final CollectionReference _categoriesRef;
+
+  FirebaseEntryApi(this.firestore, this.userId)
+      : _categoriesRef = firestore.collection('users/$userId/categories');
+
+  @override
+  Stream<List<Entry>> subscribe(String categoryId) {
+    var snapshots = _categoriesRef
+        .document('$categoryId')
+        .collection('entries')
+        .snapshots();
+    var result = snapshots.map((querySnapshot) {
+      return querySnapshot.documents.map((snapshot) {
+        return Entry.fromJson(snapshot.data)..id = snapshot.documentID;
+      }).toList();
+    });
+
+    return result;
+  }
+
+  @override
+  Future<Entry> delete(String categoryId, String id) async {
+    var document = _categoriesRef.document('$categoryId/entries/$id');
+    var entry = await get(categoryId, document.documentID);
+
+    await document.delete();
+
+    return entry;
+  }
+
+  @override
+  Future<Entry> insert(String categoryId, Entry entry) async {
+    var document = await _categoriesRef
+        .document('$categoryId')
+        .collection('entries')
+        .add(entry.toJson());
+    return await get(categoryId, document.documentID);
+  }
+
+  @override
+  Future<List<Entry>> list(String categoryId) async {
+    var entriesRef =
+        _categoriesRef.document('$categoryId').collection('entries');
+    var querySnapshot = await entriesRef.getDocuments();
+    var entries = querySnapshot.documents
+        .map((doc) => Entry.fromJson(doc.data)..id = doc.documentID)
+        .toList();
+
+    return entries;
+  }
+
+  @override
+  Future<Entry> update(String categoryId, String id, Entry entry) async {
+    var document = _categoriesRef.document('$categoryId/entries/$id');
+    await document.setData(entry.toJson());
+    var snapshot = await document.get();
+    return Entry.fromJson(snapshot.data)..id = snapshot.documentID;
+  }
+
+  @override
+  Future<Entry> get(String categoryId, String id) async {
+    var document = _categoriesRef.document('$categoryId/entries/$id');
+    var snapshot = await document.get();
+    return Entry.fromJson(snapshot.data)..id = snapshot.documentID;
+  }
+}
+
+class FirebaseCategoryApi implements CategoryApi {
+  final Firestore firestore;
+  final String userId;
+  final CollectionReference _categoriesRef;
+
+  FirebaseCategoryApi(this.firestore, this.userId)
+      : _categoriesRef = firestore.collection('users/$userId/categories');
+
+  @override
+  Stream<List<Category>> subscribe() {
+    var snapshots = _categoriesRef.snapshots();
+    var result = snapshots.map((querySnapshot) {
+      return querySnapshot.documents.map((snapshot) {
+        return Category.fromJson(snapshot.data)..id = snapshot.documentID;
+      }).toList();
+    });
+
+    return result;
+  }
+
+  @override
+  Future<Category> delete(String id) async {
+    var document = _categoriesRef.document('$id');
+    var categories = await get(document.documentID);
+
+    await document.delete();
+
+    return categories;
+  }
+
+  @override
+  Future<Category> get(String id) async {
+    var document = _categoriesRef.document('$id');
+    var snapshot = await document.get();
+    return Category.fromJson(snapshot.data)..id = snapshot.documentID;
+  }
+
+  @override
+  Future<Category> insert(Category category) async {
+    var document = await _categoriesRef.add(category.toJson());
+    return await get(document.documentID);
+  }
+
+  @override
+  Future<List<Category>> list() async {
+    var querySnapshot = await _categoriesRef.getDocuments();
+    var categories = querySnapshot.documents
+        .map((doc) => Category.fromJson(doc.data)..id = doc.documentID)
+        .toList();
+
+    return categories;
+  }
+
+  @override
+  Future<Category> update(Category category, String id) async {
+    var document = _categoriesRef.document('$id');
+    await document.setData(category.toJson());
+    var snapshot = await document.get();
+    return Category.fromJson(snapshot.data)..id = snapshot.documentID;
+  }
+}

experimental/web_dashboard/lib/src/api/mock.dart

@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
+import 'dart:math';
 
 import 'package:uuid/uuid.dart' as uuid;
 
@@ -13,48 +14,67 @@ class MockDashboardApi implements DashboardApi {
   final EntryApi entries = MockEntryApi();
 
   @override
-  final ItemApi items = MockItemApi();
+  final CategoryApi categories = MockCategoryApi();
+
+  MockDashboardApi();
+
+  /// Creates a [MockDashboardApi] filled with mock data for the last 30 days.
+  Future<void> fillWithMockData() async {
+    await Future<void>.delayed(Duration(seconds: 1));
+    var category1 = await categories.insert(Category('Coffee (oz)'));
+    var category2 = await categories.insert(Category('Running (miles)'));
+    var category3 = await categories.insert(Category('Git Commits'));
+    var monthAgo = DateTime.now().subtract(Duration(days: 30));
+
+    for (var category in [category1, category2, category3]) {
+      for (var i = 0; i < 30; i++) {
+        var date = monthAgo.add(Duration(days: i));
+        var value = Random().nextInt(6) + 1;
+        await entries.insert(category.id, Entry(value, date));
+      }
+    }
+  }
 }
 
-class MockItemApi implements ItemApi {
-  Map<String, Item> _storage = {};
-  StreamController<List<Item>> _streamController =
-      StreamController<List<Item>>.broadcast();
+class MockCategoryApi implements CategoryApi {
+  Map<String, Category> _storage = {};
+  StreamController<List<Category>> _streamController =
+      StreamController<List<Category>>.broadcast();
 
   @override
-  Future<Item> delete(String id) async {
+  Future<Category> delete(String id) async {
+    var removed = _storage.remove(id);
     _emit();
-    return _storage.remove(id);
+    return removed;
   }
 
   @override
-  Future<Item> get(String id) async {
+  Future<Category> get(String id) async {
     return _storage[id];
   }
 
   @override
-  Future<Item> insert(Item item) async {
+  Future<Category> insert(Category category) async {
     var id = uuid.Uuid().v4();
-    var newItem = Item(item.name)..id = id;
-    _storage[id] = newItem;
+    var newCategory = Category(category.name)..id = id;
+    _storage[id] = newCategory;
     _emit();
-    return newItem;
+    return newCategory;
   }
 
   @override
-  Future<List<Item>> list() async {
+  Future<List<Category>> list() async {
     return _storage.values.toList();
   }
 
   @override
-  Future<Item> update(Item item, String id) async {
-    _storage[id] = item;
-    return item..id = id;
+  Future<Category> update(Category category, String id) async {
+    _storage[id] = category;
+    _emit();
+    return category..id = id;
   }
 
-  Stream<List<Item>> allItemsStream() {
-    return _streamController.stream;
-  }
+  Stream<List<Category>> subscribe() => _streamController.stream;
 
   void _emit() {
     _streamController.add(_storage.values.toList());
@@ -63,44 +83,64 @@ class MockItemApi implements ItemApi {
 
 class MockEntryApi implements EntryApi {
   Map<String, Entry> _storage = {};
-  StreamController<List<Entry>> _streamController =
-      StreamController<List<Entry>>.broadcast();
+  StreamController<_EntriesEvent> _streamController =
+      StreamController.broadcast();
 
   @override
-  Future<Entry> delete(String itemId, String id) async {
-    _emit();
-    return _storage.remove('$itemId-$id');
+  Future<Entry> delete(String categoryId, String id) async {
+    _emit(categoryId);
+    return _storage.remove('$categoryId-$id');
   }
 
   @override
-  Future<Entry> insert(String itemId, Entry entry) async {
+  Future<Entry> insert(String categoryId, Entry entry) async {
     var id = uuid.Uuid().v4();
     var newEntry = Entry(entry.value, entry.time)..id = id;
-    _storage['$itemId-$id'] = newEntry;
-    _emit();
+    _storage['$categoryId-$id'] = newEntry;
+    _emit(categoryId);
     return newEntry;
   }
 
   @override
-  Future<List<Entry>> list(String itemId) async {
+  Future<List<Entry>> list(String categoryId) async {
     return _storage.keys
-        .where((k) => k.startsWith(itemId))
+        .where((k) => k.startsWith(categoryId))
         .map((k) => _storage[k])
         .toList();
   }
 
   @override
-  Future<Entry> update(String itemId, String id, Entry entry) async {
-    _storage['$itemId-$id'] = entry;
+  Future<Entry> update(String categoryId, String id, Entry entry) async {
+    _storage['$categoryId-$id'] = entry;
+    _emit(categoryId);
     return entry..id = id;
   }
 
   @override
-  Stream<List<Entry>> allEntriesStream(String itemId) {
-    return _streamController.stream;
+  Stream<List<Entry>> subscribe(String categoryId) {
+    return _streamController.stream
+        .where((event) => event.categoryId == categoryId)
+        .map((event) => event.entries);
   }
 
-  void _emit() {
-    _streamController.add(_storage.values.toList());
+  void _emit(String categoryId) {
+    var entries = _storage.keys
+        .where((k) => k.startsWith(categoryId))
+        .map((k) => _storage[k])
+        .toList();
+
+    _streamController.add(_EntriesEvent(categoryId, entries));
+  }
+
+  @override
+  Future<Entry> get(String categoryId, String id) async {
+    return _storage['$categoryId-$id'];
   }
 }
+
+class _EntriesEvent {
+  final String categoryId;
+  final List<Entry> entries;
+
+  _EntriesEvent(this.categoryId, this.entries);
+}

experimental/web_dashboard/lib/src/app.dart

@@ -2,58 +2,102 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:cloud_firestore/cloud_firestore.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
 import 'api/api.dart';
+import 'api/firebase.dart';
 import 'api/mock.dart';
+import 'auth/auth.dart';
+import 'auth/firebase.dart';
+import 'auth/mock.dart';
 import 'pages/home.dart';
-import 'widgets/third_party/adaptive_scaffold.dart';
+import 'pages/sign_in.dart';
 
-/// An app that shows a responsive dashboard.
+/// The global state the app.
+class AppState {
+  final Auth auth;
+  DashboardApi api;
+
+  AppState(this.auth);
+}
+
+/// Creates a [DashboardApi] when the user is logged in.
+typedef DashboardApi ApiBuilder(User user);
+
+/// An app that displays a personalized dashboard.
 class DashboardApp extends StatefulWidget {
+  static ApiBuilder _mockApiBuilder =
+      (user) => MockDashboardApi()..fillWithMockData();
+  static ApiBuilder _apiBuilder =
+      (user) => FirebaseDashboardApi(Firestore.instance, user.uid);
+
+  final Auth auth;
+  final ApiBuilder apiBuilder;
+
+  /// Runs the app using Firebase
+  DashboardApp()
+      : auth = FirebaseAuthService(),
+        apiBuilder = _apiBuilder;
+
+  /// Runs the app using mock data
+  DashboardApp.mock()
+      : auth = MockAuthService(),
+        apiBuilder = _mockApiBuilder;
+
   @override
   _DashboardAppState createState() => _DashboardAppState();
 }
 
 class _DashboardAppState extends State<DashboardApp> {
-  int _pageIndex = 0;
+  AppState _appState;
+
+  void initState() {
+    super.initState();
+    _appState = AppState(widget.auth);
+  }
 
   @override
   Widget build(BuildContext context) {
-    return MultiProvider(
-      providers: [
-        Provider<DashboardApi>(create: (_) => MockDashboardApi()),
-      ],
+    return Provider.value(
+      value: _appState,
       child: MaterialApp(
-        home: AdaptiveScaffold(
-          currentIndex: _pageIndex,
-          destinations: [
-            AdaptiveScaffoldDestination(title: 'Home', icon: Icons.home),
-            AdaptiveScaffoldDestination(title: 'Entries', icon: Icons.list),
-            AdaptiveScaffoldDestination(
-                title: 'Settings', icon: Icons.settings),
-          ],
-          body: _pageAtIndex(_pageIndex),
-          onNavigationIndexChange: (newIndex) {
-            setState(() {
-              _pageIndex = newIndex;
-            });
-          },
+        home: Builder(
+          builder: (context) => SignInPage(
+            auth: _appState.auth,
+            onSuccess: (user) => _handleSignIn(user, context, _appState),
+          ),
         ),
       ),
     );
   }
 
-  static Widget _pageAtIndex(int index) {
-    switch (index) {
-      case 1:
-        return Center(child: Text('page 2'));
-      case 2:
-        return Center(child: Text('page 3'));
-      case 0:
-      default:
-        return HomePage();
-    }
+  /// Sets the DashboardApi on AppState and navigates to the home page.
+  void _handleSignIn(User user, BuildContext context, AppState appState) {
+    appState.api = widget.apiBuilder(user);
+
+    _showPage(HomePage(), context);
+  }
+
+  /// Navigates to the home page using a fade transition.
+  void _showPage(Widget page, BuildContext context) {
+    var route = _fadeRoute(page);
+    Navigator.of(context).pushReplacement(route);
+  }
+
+  /// Creates a [Route] that shows [newPage] using a fade transition.
+  Route<FadeTransition> _fadeRoute(Widget newPage) {
+    return PageRouteBuilder<FadeTransition>(
+      pageBuilder: (context, animation, secondaryAnimation) {
+        return newPage;
+      },
+      transitionsBuilder: (context, animation, secondaryAnimation, child) {
+        return FadeTransition(
+          opacity: animation.drive(CurveTween(curve: Curves.ease)),
+          child: child,
+        );
+      },
+    );
   }
 }

experimental/web_dashboard/lib/src/auth/auth.dart

@@ -0,0 +1,12 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+abstract class Auth {
+  Future<User> signIn();
+  Future signOut();
+}
+
+abstract class User {
+  String get uid;
+}

experimental/web_dashboard/lib/src/auth/firebase.dart

@@ -0,0 +1,41 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:google_sign_in/google_sign_in.dart';
+import 'package:firebase_auth/firebase_auth.dart' hide FirebaseUser;
+
+import 'auth.dart';
+
+class FirebaseAuthService implements Auth {
+  final GoogleSignIn _googleSignIn = GoogleSignIn();
+  final FirebaseAuth _auth = FirebaseAuth.instance;
+
+  Future<User> signIn() async {
+    GoogleSignInAccount googleUser;
+    if (await _googleSignIn.isSignedIn()) {
+      googleUser = await _googleSignIn.signInSilently();
+    } else {
+      googleUser = await _googleSignIn.signIn();
+    }
+
+    var googleAuth = await googleUser.authentication;
+
+    var credential = GoogleAuthProvider.getCredential(
+        accessToken: googleAuth.accessToken, idToken: googleAuth.idToken);
+
+    var authResult = await _auth.signInWithCredential(credential);
+
+    return _FirebaseUser(authResult.user.uid);
+  }
+
+  Future<void> signOut() async {
+    await _auth.signOut();
+  }
+}
+
+class _FirebaseUser implements User {
+  final String uid;
+
+  _FirebaseUser(this.uid);
+}

experimental/web_dashboard/lib/src/auth/mock.dart

@@ -0,0 +1,21 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'auth.dart';
+
+class MockAuthService implements Auth {
+  @override
+  Future<User> signIn() async {
+    return MockUser();
+  }
+
+  @override
+  Future signOut() async {
+    return null;
+  }
+}
+
+class MockUser implements User {
+  String get uid => "123";
+}

experimental/web_dashboard/lib/src/pages/dashboard.dart

@@ -0,0 +1,67 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../api/api.dart';
+import '../app.dart';
+import '../widgets/category_chart.dart';
+
+class DashboardPage extends StatelessWidget {
+  Widget build(BuildContext context) {
+    var appState = Provider.of<AppState>(context);
+    return FutureBuilder<List<Category>>(
+      future: appState.api.categories.list(),
+      builder: (context, futureSnapshot) {
+        if (!futureSnapshot.hasData) {
+          return Center(
+            child: CircularProgressIndicator(),
+          );
+        }
+        return StreamBuilder<List<Category>>(
+          initialData: futureSnapshot.data,
+          stream: appState.api.categories.subscribe(),
+          builder: (context, snapshot) {
+            if (snapshot.data == null) {
+              return Center(
+                child: CircularProgressIndicator(),
+              );
+            }
+            return Dashboard(snapshot.data);
+          },
+        );
+      },
+    );
+  }
+}
+
+class Dashboard extends StatelessWidget {
+  final List<Category> categories;
+
+  Dashboard(this.categories);
+
+  @override
+  Widget build(BuildContext context) {
+    var api = Provider.of<AppState>(context).api;
+    return Scrollbar(
+      child: GridView(
+        gridDelegate: SliverGridDelegateWithMaxCrossAxisExtent(
+          childAspectRatio: 2,
+          maxCrossAxisExtent: 500,
+        ),
+        children: [
+          ...categories.map(
+            (category) => Card(
+              child: CategoryChart(
+                category: category,
+                api: api,
+              ),
+            ),
+          )
+        ],
+      ),
+    );
+  }
+}

experimental/web_dashboard/lib/src/pages/entries.dart

@@ -0,0 +1,161 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:intl/intl.dart' as intl;
+
+import '../api/api.dart';
+import '../app.dart';
+import '../widgets/categories_dropdown.dart';
+import '../widgets/dialogs.dart';
+
+class EntriesPage extends StatefulWidget {
+  @override
+  _EntriesPageState createState() => _EntriesPageState();
+}
+
+class _EntriesPageState extends State<EntriesPage> {
+  Category _selected;
+
+  @override
+  Widget build(BuildContext context) {
+    var appState = Provider.of<AppState>(context);
+    return Column(
+      children: [
+        CategoryDropdown(
+            api: appState.api.categories,
+            onSelected: (category) => setState(() => _selected = category)),
+        Expanded(
+          child: _selected == null
+              ? Center(child: CircularProgressIndicator())
+              : EntriesList(
+                  category: _selected,
+                  api: appState.api.entries,
+                ),
+        ),
+      ],
+    );
+  }
+}
+
+class EntriesList extends StatefulWidget {
+  final Category category;
+  final EntryApi api;
+
+  EntriesList({
+    @required this.category,
+    @required this.api,
+  }) : super(key: ValueKey(category.id));
+
+  @override
+  _EntriesListState createState() => _EntriesListState();
+}
+
+class _EntriesListState extends State<EntriesList> {
+  @override
+  Widget build(BuildContext context) {
+    if (widget.category == null) {
+      return _buildLoadingIndicator();
+    }
+
+    return FutureBuilder<List<Entry>>(
+      future: widget.api.list(widget.category.id),
+      builder: (context, futureSnapshot) {
+        if (!futureSnapshot.hasData) {
+          return _buildLoadingIndicator();
+        }
+        return StreamBuilder<List<Entry>>(
+          initialData: futureSnapshot.data,
+          stream: widget.api.subscribe(widget.category.id),
+          builder: (context, snapshot) {
+            if (!snapshot.hasData) {
+              return _buildLoadingIndicator();
+            }
+            return ListView.builder(
+              itemBuilder: (context, index) {
+                return EntryTile(
+                  category: widget.category,
+                  entry: snapshot.data[index],
+                );
+              },
+              itemCount: snapshot.data.length,
+            );
+          },
+        );
+      },
+    );
+  }
+
+  Widget _buildLoadingIndicator() {
+    return Center(child: CircularProgressIndicator());
+  }
+}
+
+class EntryTile extends StatelessWidget {
+  final Category category;
+  final Entry entry;
+
+  EntryTile({
+    this.category,
+    this.entry,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return ListTile(
+      title: Text(entry.value.toString()),
+      subtitle: Text(intl.DateFormat('MM/dd/yy h:mm a').format(entry.time)),
+      trailing: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          FlatButton(
+            child: Text('Edit'),
+            onPressed: () {
+              showDialog<void>(
+                context: context,
+                builder: (context) {
+                  return EditEntryDialog(category: category, entry: entry);
+                },
+              );
+            },
+          ),
+          FlatButton(
+            child: Text('Delete'),
+            onPressed: () async {
+              var shouldDelete = await showDialog<bool>(
+                context: context,
+                builder: (context) => AlertDialog(
+                  title: Text('Delete entry?'),
+                  actions: [
+                    FlatButton(
+                      child: Text('Cancel'),
+                      onPressed: () => Navigator.of(context).pop(false),
+                    ),
+                    FlatButton(
+                      child: Text('Delete'),
+                      onPressed: () => Navigator.of(context).pop(true),
+                    ),
+                  ],
+                ),
+              );
+              if (shouldDelete) {
+                await Provider.of<AppState>(context, listen: false)
+                    .api
+                    .entries
+                    .delete(category.id, entry.id);
+
+                Scaffold.of(context).showSnackBar(
+                  SnackBar(
+                    content: Text('Entry deleted'),
+                  ),
+                );
+              }
+            },
+          ),
+        ],
+      ),
+    );
+  }
+}

experimental/web_dashboard/lib/src/pages/home.dart

@@ -3,47 +3,79 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:flutter/material.dart';
-import 'package:provider/provider.dart';
 
-import '../api/api.dart';
-import 'item_details.dart';
+import '../widgets/dialogs.dart';
+import '../widgets/third_party/adaptive_scaffold.dart';
+import 'dashboard.dart';
+import 'entries.dart';
 
-class HomePage extends StatelessWidget {
+class HomePage extends StatefulWidget {
+  @override
+  _HomePageState createState() => _HomePageState();
+}
+
+class _HomePageState extends State<HomePage> {
+  int _pageIndex = 0;
+
+  @override
   Widget build(BuildContext context) {
-    var api = Provider.of<DashboardApi>(context);
-
-    return Scaffold(
-      body: StreamProvider<List<Item>>(
-        initialData: [],
-        create: (context) => api.items.allItemsStream(),
-        child: Consumer<List<Item>>(
-          builder: (context, items, child) {
-            return ListView.builder(
-              itemBuilder: (context, idx) {
-                return ListTile(
-                  title: Text(items[idx].name),
-                  onTap: () {
-                    _showDetails(items[idx], context);
-                  },
-                );
-              },
-              itemCount: items.length,
-            );
-          },
-        ),
-      ),
-      floatingActionButton: FloatingActionButton(
-        child: Icon(Icons.add),
-        onPressed: () {
-          api.items.insert(Item('Coffees Drank'));
-        },
-      ),
+    return AdaptiveScaffold(
+      currentIndex: _pageIndex,
+      destinations: [
+        AdaptiveScaffoldDestination(title: 'Home', icon: Icons.home),
+        AdaptiveScaffoldDestination(title: 'Entries', icon: Icons.list),
+        AdaptiveScaffoldDestination(title: 'Settings', icon: Icons.settings),
+      ],
+      body: _pageAtIndex(_pageIndex),
+      onNavigationIndexChange: (newIndex) {
+        setState(() {
+          _pageIndex = newIndex;
+        });
+      },
+      floatingActionButton:
+          _hasFloatingActionButton ? _buildFab(context) : null,
     );
   }
 
-  void _showDetails(Item item, BuildContext context) {
-    Navigator.of(context).push(MaterialPageRoute(builder: (context) {
-      return ItemDetailsPage(item);
-    }));
+  bool get _hasFloatingActionButton {
+    if (_pageIndex == 2) return false;
+    return true;
+  }
+
+  FloatingActionButton _buildFab(BuildContext context) {
+    return FloatingActionButton(
+      child: Icon(Icons.add),
+      onPressed: () => _handleFabPressed(),
+    );
+  }
+
+  void _handleFabPressed() {
+    if (_pageIndex == 0) {
+      showDialog<NewCategoryDialog>(
+        context: context,
+        builder: (context) => NewCategoryDialog(),
+      );
+      return;
+    }
+
+    if (_pageIndex == 1) {
+      showDialog<NewEntryDialog>(
+        context: context,
+        builder: (context) => NewEntryDialog(),
+      );
+      return;
+    }
+  }
+
+  Widget _pageAtIndex(int index) {
+    if (index == 0) {
+      return DashboardPage();
+    }
+
+    if (index == 1) {
+      return EntriesPage();
+    }
+
+    return Center(child: Text('Settings page'));
   }
 }

experimental/web_dashboard/lib/src/pages/item_details.dart

@@ -1,22 +0,0 @@
-// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'package:flutter/material.dart';
-import 'package:web_dashboard/src/api/api.dart';
-
-class ItemDetailsPage extends StatelessWidget {
-  final Item item;
-
-  ItemDetailsPage(this.item);
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      appBar: AppBar(),
-      body: Center(
-        child: Text('${item.name}'),
-      ),
-    );
-  }
-}

experimental/web_dashboard/lib/src/pages/sign_in.dart

@@ -0,0 +1,46 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+
+import '../auth/auth.dart';
+
+class SignInPage extends StatefulWidget {
+  final Auth auth;
+  final ValueChanged<User> onSuccess;
+
+  SignInPage({
+    @required this.auth,
+    @required this.onSuccess,
+  });
+
+  @override
+  _SignInPageState createState() => _SignInPageState();
+}
+
+class _SignInPageState extends State<SignInPage> {
+  @override
+  void initState() {
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: Center(
+        child: RaisedButton(
+          child: Text('Sign In'),
+          onPressed: () async {
+            var user = await widget.auth.signIn();
+            if (user != null) {
+              widget.onSuccess(user);
+            } else {
+              throw ('Unable to sign in');
+            }
+          },
+        ),
+      ),
+    );
+  }
+}

experimental/web_dashboard/lib/src/utils/chart_utils.dart

@@ -0,0 +1,65 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import '../api/api.dart';
+import 'day_helpers.dart';
+
+/// The total value of one or more [Entry]s on a given day.
+class EntryTotal {
+  final DateTime day;
+  int value;
+
+  EntryTotal(this.day, this.value);
+}
+
+/// Returns a list of [EntryTotal] objects. Each [EntryTotal] is the sum of
+/// the values of all the entries on a given day.
+List<EntryTotal> entryTotalsByDay(List<Entry> entries, int daysAgo,
+    {DateTime today}) {
+  today ??= DateTime.now();
+  return _entryTotalsByDay(entries, daysAgo, today).toList();
+}
+
+Iterable<EntryTotal> _entryTotalsByDay(
+    List<Entry> entries, int daysAgo, DateTime today) sync* {
+  var start = today.subtract(Duration(days: daysAgo));
+  var entriesByDay = _entriesInRange(start, today, entries);
+
+  for (var i = 0; i < entriesByDay.length; i++) {
+    var list = entriesByDay[i];
+    var entryTotal = EntryTotal(start.add(Duration(days: i)), 0);
+
+    for (var entry in list) {
+      entryTotal.value += entry.value;
+    }
+
+    yield entryTotal;
+  }
+}
+
+/// Groups entries by day between [start] and [end]. The result is a list of
+/// lists. The outer list represents the number of days since [start], and the
+/// inner list is the group of entries on that day.
+List<List<Entry>> _entriesInRange(
+        DateTime start, DateTime end, List<Entry> entries) =>
+    _entriesInRangeImpl(start, end, entries).toList();
+
+Iterable<List<Entry>> _entriesInRangeImpl(
+    DateTime start, DateTime end, List<Entry> entries) sync* {
+  start = start.atMidnight;
+  end = end.atMidnight;
+  var d = start;
+
+  while (d.compareTo(end) <= 0) {
+    var es = <Entry>[];
+    for (var entry in entries) {
+      if (d.isSameDay(entry.time.atMidnight)) {
+        es.add(entry);
+      }
+    }
+
+    yield es;
+    d = d.add(Duration(days: 1));
+  }
+}

experimental/web_dashboard/lib/src/utils/day_helpers.dart

@@ -0,0 +1,15 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+extension DayUtils on DateTime {
+  /// The UTC date portion of a datetime, without the minutes, seconds, etc.
+  DateTime get atMidnight {
+    return DateTime.utc(year, month, day);
+  }
+
+  /// Checks that the two [DateTime]s share the same date.
+  bool isSameDay(DateTime d2) {
+    return this.year == d2.year && this.month == d2.month && this.day == d2.day;
+  }
+}

experimental/web_dashboard/lib/src/widgets/categories_dropdown.dart

@@ -0,0 +1,108 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import '../api/api.dart';
+
+/// Subscribes to the latest list of categories and allows the user to select
+/// one.
+class CategoryDropdown extends StatefulWidget {
+  final CategoryApi api;
+  final ValueChanged<Category> onSelected;
+
+  CategoryDropdown({
+    @required this.api,
+    @required this.onSelected,
+  });
+
+  @override
+  _CategoryDropdownState createState() => _CategoryDropdownState();
+}
+
+class _CategoryDropdownState extends State<CategoryDropdown> {
+  Category _selected;
+  Future<List<Category>> _future;
+  Stream<List<Category>> _stream;
+
+  void initState() {
+    super.initState();
+
+    // This widget needs to wait for the list of Categories, select the first
+    // Category, and emit an `onSelected` event.
+    //
+    // This could be done inside the FutureBuilder's `builder` callback,
+    // but calling setState() during the build is an error. (Calling the
+    // onSelected callback will also cause the parent widget to call
+    // setState()).
+    //
+    // Instead, we'll create a new Future that sets the selected Category and
+    // calls `onSelected` if necessary. Then, we'll pass *that* future to
+    // FutureBuilder. Now the selected category is set and events are emitted
+    // *before* the build is triggered by the FutureBuilder.
+    _future = widget.api.list().then((categories) {
+      if (categories.isEmpty) {
+        return categories;
+      }
+
+      _setSelected(categories.first);
+      return categories;
+    });
+
+    // Same here, we'll create a new stream that handles any potential
+    // setState() operations before we trigger our StreamBuilder.
+    _stream = widget.api.subscribe().map((categories) {
+      if (!categories.contains(_selected) && categories.isNotEmpty) {
+        _setSelected(categories.first);
+      }
+
+      return categories;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return FutureBuilder<List<Category>>(
+      future: _future,
+      builder: (context, futureSnapshot) {
+        // Show an empty dropdown while the data is loading.
+        if (!futureSnapshot.hasData) {
+          return DropdownButton<Category>(items: [], onChanged: null);
+        }
+
+        return StreamBuilder<List<Category>>(
+          initialData: futureSnapshot.hasData ? futureSnapshot.data : [],
+          stream: _stream,
+          builder: (context, snapshot) {
+            var data = snapshot.hasData ? snapshot.data : <Category>[];
+            return DropdownButton<Category>(
+              value: _selected,
+              items: data.map(_buildDropdownItem).toList(),
+              onChanged: (category) {
+                _setSelected(category);
+              },
+            );
+          },
+        );
+      },
+    );
+  }
+
+  void _setSelected(Category category) {
+    if (_selected == category) {
+      return;
+    }
+    setState(() {
+      _selected = category;
+    });
+
+    widget.onSelected(_selected);
+  }
+
+  DropdownMenuItem<Category> _buildDropdownItem(Category category) {
+    return DropdownMenuItem<Category>(
+        child: Text(category.name), value: category);
+  }
+}

experimental/web_dashboard/lib/src/widgets/category_chart.dart

@@ -0,0 +1,111 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+
+import 'package:charts_flutter/flutter.dart' as charts;
+import 'package:intl/intl.dart' as intl;
+
+import '../api/api.dart';
+import '../utils/chart_utils.dart' as utils;
+import 'dialogs.dart';
+
+// The number of days to show in the chart
+const _daysBefore = 10;
+
+class CategoryChart extends StatelessWidget {
+  final Category category;
+  final DashboardApi api;
+
+  CategoryChart({
+    @required this.category,
+    @required this.api,
+  });
+
+  Widget build(BuildContext context) {
+    return Column(
+      children: [
+        Padding(
+          padding: const EdgeInsets.only(left: 8.0, right: 8.0),
+          child: Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            children: [
+              Text(category.name),
+              IconButton(
+                icon: Icon(Icons.settings),
+                onPressed: () {
+                  showDialog<EditCategoryDialog>(
+                    context: context,
+                    builder: (context) {
+                      return EditCategoryDialog(category: category);
+                    },
+                  );
+                },
+              ),
+            ],
+          ),
+        ),
+        Expanded(
+          // Load the initial snapshot using a FutureBuilder, and subscribe to
+          // additional updates with a StreamBuilder.
+          child: FutureBuilder<List<Entry>>(
+            future: api.entries.list(category.id),
+            builder: (context, futureSnapshot) {
+              if (!futureSnapshot.hasData) {
+                return _buildLoadingIndicator();
+              }
+              return StreamBuilder<List<Entry>>(
+                initialData: futureSnapshot.data,
+                stream: api.entries.subscribe(category.id),
+                builder: (context, snapshot) {
+                  if (!snapshot.hasData) {
+                    return _buildLoadingIndicator();
+                  }
+                  return _BarChart(entries: snapshot.data);
+                },
+              );
+            },
+          ),
+        ),
+      ],
+    );
+  }
+
+  Widget _buildLoadingIndicator() {
+    return Center(child: CircularProgressIndicator());
+  }
+}
+
+class _BarChart extends StatelessWidget {
+  final List<Entry> entries;
+
+  _BarChart({this.entries});
+
+  @override
+  Widget build(BuildContext context) {
+    return charts.BarChart(
+      [_seriesData()],
+      animate: false,
+    );
+  }
+
+  charts.Series<utils.EntryTotal, String> _seriesData() {
+    return charts.Series<utils.EntryTotal, String>(
+      id: 'Entries',
+      colorFn: (_, __) => charts.MaterialPalette.blue.shadeDefault,
+      domainFn: (entryTotal, _) {
+        if (entryTotal == null) return null;
+
+        var format = intl.DateFormat.Md();
+        return format.format(entryTotal.day);
+      },
+      measureFn: (total, _) {
+        if (total == null) return null;
+
+        return total.value;
+      },
+      data: utils.entryTotalsByDay(entries, _daysBefore),
+    );
+  }
+}

experimental/web_dashboard/lib/src/widgets/category_forms.dart

@@ -0,0 +1,103 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:web_dashboard/src/api/api.dart';
+import 'package:web_dashboard/src/app.dart';
+
+class NewCategoryForm extends StatefulWidget {
+  @override
+  _NewCategoryFormState createState() => _NewCategoryFormState();
+}
+
+class _NewCategoryFormState extends State<NewCategoryForm> {
+  Category _category = Category('');
+
+  @override
+  Widget build(BuildContext context) {
+    var api = Provider.of<AppState>(context).api;
+    return EditCategoryForm(
+      category: _category,
+      onDone: (shouldInsert) {
+        if (shouldInsert) {
+          api.categories.insert(_category);
+        }
+        Navigator.of(context).pop();
+      },
+    );
+  }
+}
+
+class EditCategoryForm extends StatefulWidget {
+  final Category category;
+  final ValueChanged<bool> onDone;
+
+  EditCategoryForm({
+    @required this.category,
+    @required this.onDone,
+  });
+
+  @override
+  _EditCategoryFormState createState() => _EditCategoryFormState();
+}
+
+class _EditCategoryFormState extends State<EditCategoryForm> {
+  final _formKey = GlobalKey<FormState>();
+
+  @override
+  Widget build(BuildContext context) {
+    return Form(
+      key: _formKey,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: TextFormField(
+              initialValue: widget.category.name,
+              decoration: InputDecoration(
+                labelText: 'Name',
+              ),
+              onChanged: (newValue) {
+                widget.category.name = newValue;
+              },
+              validator: (value) {
+                if (value.isEmpty) {
+                  return 'Please enter a name';
+                }
+                return null;
+              },
+            ),
+          ),
+          Row(
+            mainAxisAlignment: MainAxisAlignment.end,
+            children: [
+              Padding(
+                padding: const EdgeInsets.only(left: 8.0, right: 8.0),
+                child: RaisedButton(
+                  child: Text('Cancel'),
+                  onPressed: () {
+                    widget.onDone(false);
+                  },
+                ),
+              ),
+              Padding(
+                padding: const EdgeInsets.only(left: 8.0, right: 8.0),
+                child: RaisedButton(
+                  child: Text('OK'),
+                  onPressed: () {
+                    if (_formKey.currentState.validate()) {
+                      widget.onDone(true);
+                    }
+                  },
+                ),
+              ),
+            ],
+          ),
+        ],
+      ),
+    );
+  }
+}

experimental/web_dashboard/lib/src/widgets/dialogs.dart

@@ -0,0 +1,98 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:web_dashboard/src/api/api.dart';
+import 'package:web_dashboard/src/widgets/category_forms.dart';
+
+import '../app.dart';
+import 'edit_entry.dart';
+
+class NewCategoryDialog extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return SimpleDialog(
+      title: Text('New Category'),
+      children: <Widget>[
+        NewCategoryForm(),
+      ],
+    );
+  }
+}
+
+class EditCategoryDialog extends StatelessWidget {
+  final Category category;
+
+  EditCategoryDialog({
+    @required this.category,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    var api = Provider.of<AppState>(context).api;
+
+    return SimpleDialog(
+      title: Text('Edit Category'),
+      children: [
+        EditCategoryForm(
+          category: category,
+          onDone: (shouldUpdate) {
+            if (shouldUpdate) {
+              api.categories.update(category, category.id);
+            }
+            Navigator.of(context).pop();
+          },
+        ),
+      ],
+    );
+  }
+}
+
+class NewEntryDialog extends StatefulWidget {
+  @override
+  _NewEntryDialogState createState() => _NewEntryDialogState();
+}
+
+class _NewEntryDialogState extends State<NewEntryDialog> {
+  @override
+  Widget build(BuildContext context) {
+    return SimpleDialog(
+      title: Text('New Entry'),
+      children: [
+        NewEntryForm(),
+      ],
+    );
+  }
+}
+
+class EditEntryDialog extends StatelessWidget {
+  final Category category;
+  final Entry entry;
+
+  EditEntryDialog({
+    this.category,
+    this.entry,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    var api = Provider.of<AppState>(context).api;
+
+    return SimpleDialog(
+      title: Text('Edit Entry'),
+      children: [
+        EditEntryForm(
+          entry: entry,
+          onDone: (shouldUpdate) {
+            if (shouldUpdate) {
+              api.entries.update(category.id, entry.id, entry);
+            }
+            Navigator.of(context).pop();
+          },
+        )
+      ],
+    );
+  }
+}

experimental/web_dashboard/lib/src/widgets/edit_entry.dart

@@ -0,0 +1,154 @@
+// Copyright 2020, the Flutter project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:web_dashboard/src/api/api.dart';
+import 'package:intl/intl.dart' as intl;
+
+import '../app.dart';
+import 'categories_dropdown.dart';
+
+class NewEntryForm extends StatefulWidget {
+  @override
+  _NewEntryFormState createState() => _NewEntryFormState();
+}
+
+class _NewEntryFormState extends State<NewEntryForm> {
+  Category _selected;
+  Entry _entry = Entry(0, DateTime.now());
+
+  @override
+  Widget build(BuildContext context) {
+    var api = Provider.of<AppState>(context).api;
+
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: <Widget>[
+        Padding(
+          padding: const EdgeInsets.all(8.0),
+          child: CategoryDropdown(
+            api: api.categories,
+            onSelected: (category) {
+              setState(() {
+                _selected = category;
+              });
+            },
+          ),
+        ),
+        EditEntryForm(
+          entry: _entry,
+          onDone: (shouldInsert) {
+            if (shouldInsert) {
+              api.entries.insert(_selected.id, _entry);
+            }
+            Navigator.of(context).pop();
+          },
+        ),
+      ],
+    );
+  }
+}
+
+class EditEntryForm extends StatefulWidget {
+  final Entry entry;
+  final ValueChanged<bool> onDone;
+
+  EditEntryForm({
+    @required this.entry,
+    @required this.onDone,
+  });
+
+  @override
+  _EditEntryFormState createState() => _EditEntryFormState();
+}
+
+class _EditEntryFormState extends State<EditEntryForm> {
+  final _formKey = GlobalKey<FormState>();
+
+  @override
+  Widget build(BuildContext context) {
+    return Form(
+      key: _formKey,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Padding(
+            padding: EdgeInsets.all(8),
+            child: TextFormField(
+              initialValue: widget.entry.value.toString(),
+              decoration: InputDecoration(labelText: 'Value'),
+              keyboardType: TextInputType.number,
+              validator: (value) {
+                try {
+                  int.parse(value);
+                } catch (e) {
+                  return "Please enter a whole number";
+                }
+                return null;
+              },
+              onChanged: (newValue) {
+                try {
+                  widget.entry.value = int.parse(newValue);
+                } on FormatException {
+                  print('Entry cannot contain "$newValue". Expected a number');
+                }
+              },
+            ),
+          ),
+          Padding(
+            padding: EdgeInsets.all(8),
+            child: Row(
+              mainAxisAlignment: MainAxisAlignment.spaceBetween,
+              children: [
+                Text(intl.DateFormat('MM/dd/yyyy').format(widget.entry.time)),
+                RaisedButton(
+                  child: Text('Edit'),
+                  onPressed: () async {
+                    var result = await showDatePicker(
+                        context: context,
+                        initialDate: widget.entry.time,
+                        firstDate: DateTime.now().subtract(Duration(days: 365)),
+                        lastDate: DateTime.now());
+                    if (result == null) {
+                      return;
+                    }
+                    setState(() {
+                      widget.entry.time = result;
+                    });
+                  },
+                )
+              ],
+            ),
+          ),
+          Row(
+            mainAxisAlignment: MainAxisAlignment.end,
+            children: [
+              Padding(
+                padding: const EdgeInsets.only(left: 8.0, right: 8.0),
+                child: RaisedButton(
+                  child: Text('Cancel'),
+                  onPressed: () {
+                    widget.onDone(false);
+                  },
+                ),
+              ),
+              Padding(
+                padding: const EdgeInsets.only(left: 8.0, right: 8.0),
+                child: RaisedButton(
+                  child: Text('OK'),
+                  onPressed: () {
+                    if (_formKey.currentState.validate()) {
+                      widget.onDone(true);
+                    }
+                  },
+                ),
+              ),
+            ],
+          )
+        ],
+      ),
+    );
+  }
+}