Show the tasks linked to an event on its screen

lib/src/blocs/event_bloc.dart

@@ -1,19 +1,54 @@
 import 'dart:async';
-import 'package:meta/meta.dart';
 
+import 'package:meta/meta.dart';
+import 'package:rxdart/rxdart.dart';
+
+import '../models/task_model.dart';
 import '../resources/firestore_provider.dart';
 import '../resources/firebase_storage_provider.dart';
+import '../services/auth_service.dart';
+import '../utils.dart' show kTaskListPriorityTransforemer;
 
 /// A business logic component that manages the state for an event screen.
 class EventBloc {
   /// The name of the event being shown.
   final String eventName;
+
+  /// An instance of a firestore provider.
+  final FirestoreProvider _firestore = firestoreProvider;
+
+  /// An instace of the auth service.
+  final AuthService _auth = authService;
+
+  /// A subject of list of task model.
+  final _tasks = BehaviorSubject<List<TaskModel>>();
+
+  // Stream getters.
+  /// An observable of the tasks linked to the event.
+  Observable<List<TaskModel>> get eventTasks =>
+      _tasks.stream.transform(kTaskListPriorityTransforemer);
+
   EventBloc({
     @required this.eventName,
   });
 
   /// Fetches the tasks for the current user that a part of the currently
   /// selected event.
-  void fetchTasks() {}
-  void dispose() {}
+  Future<void> fetchTasks() async {
+    final user = await _auth.currentUser;
+    _firestore.getUserTasks(user.email, event: eventName).pipe(_tasks);
+  }
+
+  /// Marks a task as done in the database.
+  void markTaskAsDone(TaskModel task) async {
+    _firestore.updateTask(
+      task.id,
+      done: true,
+    );
+  }
+
+  void dispose() async {
+    await _tasks.drain();
+    _tasks.close();
+  }
 }

lib/src/blocs/home_bloc.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 
 import 'package:rxdart/rxdart.dart';
 
+import '../utils.dart' show kTaskListPriorityTransforemer;
 import '../models/task_model.dart';
 import '../resources/firestore_provider.dart';
 import '../services/auth_service.dart';
@@ -41,21 +42,13 @@ class HomeBloc {
         (text, tasks) {
           return tasks;
         },
-      ).transform(searchBoxTransformer()).transform(prioritySortTransformer());
+      )
+          .transform(searchBoxTransformer())
+          .transform(kTaskListPriorityTransforemer);
 
   /// An observable of the current logged in user.
   Observable<FirebaseUser> get userStream => _auth.userStream;
 
-  /// Returns a stream transformer that sorts the tasks by priority.
-  StreamTransformer<List<TaskModel>, List<TaskModel>>
-      prioritySortTransformer() {
-    return StreamTransformer.fromHandlers(handleData: (tasksList, sink) {
-      tasksList.sort((a, b) => TaskModel.ecodedPriority(b.priority)
-          .compareTo(TaskModel.ecodedPriority(a.priority)));
-      sink.add(tasksList);
-    });
-  }
-
   // TODO: Include the priority in the filtering.
   /// Returns a stream transformer that filters the task with the text from
   /// the search box.

lib/src/screens/event_screen.dart

@@ -1,8 +1,11 @@
 import 'package:flutter/material.dart';
 
-import '../utils.dart';
+import '../utils.dart' show kBigTextStyle;
 import '../blocs/event_bloc.dart';
+import '../models/task_model.dart';
 import '../widgets/custom_app_bar.dart';
+import '../widgets/loading_indicator.dart';
+import '../widgets/task_list_tile.dart';
 
 class EventScreen extends StatefulWidget {
   /// The name of the event this screenn is showing.
@@ -22,6 +25,7 @@ class _EventScreenState extends State<EventScreen>
   initState() {
     super.initState();
     bloc = EventBloc(eventName: widget.eventName);
+    bloc.fetchTasks();
     _tabController = TabController(vsync: this, length: 2);
   }
 
@@ -31,12 +35,7 @@ class _EventScreenState extends State<EventScreen>
       body: TabBarView(
         controller: _tabController,
         children: <Widget>[
-          Center(
-            child: Text(
-              'Tasks',
-              style: kBigTextStyle,
-            ),
-          ),
+          buildTasksListView(),
           Center(
             child: Text(
               'Media',
@@ -65,6 +64,38 @@ class _EventScreenState extends State<EventScreen>
     );
   }
 
+  Widget buildTasksListView() {
+    return StreamBuilder(
+      stream: bloc.eventTasks,
+      builder: (BuildContext context, AsyncSnapshot<List<TaskModel>> snap) {
+        if (!snap.hasData) {
+          return Center(
+            child: LoadingIndicator(),
+          );
+        }
+
+        return ListView(
+          padding: EdgeInsets.only(top: 15),
+          children: snap.data
+              .map((task) => Container(
+                    child: TaskListTile(
+                      task: task,
+                      hideEventButton: true,
+                      onDone: () => bloc.markTaskAsDone(task),
+                      onEditPressed: () {
+                        // Include the id of the task to be edited in the route.
+                        Navigator.of(context).pushNamed('editTask/${task.id}');
+                      },
+                    ),
+                    padding: EdgeInsets.only(bottom: 12),
+                  ))
+              .toList()
+                ..add(Container(height: 70)),
+        );
+      },
+    );
+  }
+
   void dispose() {
     bloc.dispose();
     super.dispose();

lib/src/utils.dart

@@ -51,3 +51,12 @@ class Validators {
     },
   );
 }
+
+/// Returns a stream transformer that sorts tasks by priority.
+final StreamTransformer<List<TaskModel>, List<TaskModel>>
+    kTaskListPriorityTransforemer =
+    StreamTransformer.fromHandlers(handleData: (tasksList, sink) {
+  tasksList.sort((a, b) => TaskModel.ecodedPriority(b.priority)
+      .compareTo(TaskModel.ecodedPriority(a.priority)));
+  sink.add(tasksList);
+});

lib/src/widgets/custom_app_bar.dart

@@ -13,14 +13,20 @@ class CustomAppBar extends StatelessWidget implements PreferredSizeWidget {
   final PreferredSizeWidget bottom;
 
   /// The size of only the app bar part.
-  final double appBarHeight;
+  ///
+  /// It will vary depending on the existance of the bottom widget.
+  final double _appBarHeight;
+
   CustomAppBar({
     this.title = '',
     this.bottom,
-  }) : appBarHeight = bottom == null ? 140.0 : 120.0;
+  }) : _appBarHeight = bottom == null ? 140.0 : 120.0;
 
+  /// The preferred size of the app bar.
+  ///
+  /// Consider the size of the bottom widget if there is one.
   Size get preferredSize =>
-      Size.fromHeight(appBarHeight + (bottom?.preferredSize?.height ?? 0));
+      Size.fromHeight(_appBarHeight + (bottom?.preferredSize?.height ?? 0));
 
   Widget build(BuildContext context) {
     Widget result = Container(

lib/src/widgets/task_list_tile.dart

@@ -19,6 +19,9 @@ class TaskListTile extends StatelessWidget {
   /// Function to be called when the "event" button is pressed.
   final VoidCallback onEventPressed;
 
+  /// Whether or not the event button should be hidden.
+  final bool hideEventButton;
+
   /// Height of the priority badge.
   ///
   /// Also used to calculate the padding for the first section.
@@ -33,6 +36,7 @@ class TaskListTile extends StatelessWidget {
     this.onDone,
     this.onEditPressed,
     this.onEventPressed,
+    this.hideEventButton = false,
   }) : assert(task != null);
 
   Widget build(BuildContext context) {
@@ -96,6 +100,26 @@ class TaskListTile extends StatelessWidget {
 
   /// Builds the section that contains the 3 buttons for the tile.
   Widget buildButtonSection() {
+    final bottomRowChildren = <Widget>[];
+    if (!hideEventButton) {
+      bottomRowChildren.addAll([
+        ActionButton(
+          onPressed: onEditPressed,
+          text: 'Edit',
+          leadingIconData: Icons.edit,
+        ),
+        SizedBox(
+          width: 4,
+        ),
+      ]);
+    }
+    bottomRowChildren.add(
+      ActionButton(
+        onPressed: onEventPressed,
+        text: 'Event',
+        leadingIconData: FontAwesomeIcons.calendar,
+      ),
+    );
     return Expanded(
       flex: 5,
       child: Column(
@@ -113,21 +137,7 @@ class TaskListTile extends StatelessWidget {
           ),
           Row(
             mainAxisAlignment: MainAxisAlignment.end,
-            children: <Widget>[
-              ActionButton(
-                onPressed: onEditPressed,
-                text: 'Edit',
-                leadingIconData: Icons.edit,
-              ),
-              SizedBox(
-                width: 4,
-              ),
-              ActionButton(
-                onPressed: onEventPressed,
-                text: 'Event',
-                leadingIconData: FontAwesomeIcons.calendar,
-              )
-            ],
+            children: bottomRowChildren,
           ),
         ],
       ),