Display the list of notifications

lib/ui/screens/notifications_screen.dart

@@ -4,8 +4,10 @@ import 'package:comunic/helpers/users_helper.dart';
 import 'package:comunic/lists/groups_list.dart';
 import 'package:comunic/lists/notifications_list.dart';
 import 'package:comunic/lists/users_list.dart';
+import 'package:comunic/ui/widgets/account_image_widget.dart';
 import 'package:comunic/utils/intl_utils.dart';
 import 'package:comunic/utils/ui_utils.dart';
+import 'package:comunic/models/notification.dart' as n;
 import 'package:flutter/material.dart';
 
 /// Notifications screen
@@ -70,12 +72,7 @@ class _NotificationsScreenState extends State<NotificationsScreen> {
     return Column(
       children: [
         Expanded(
-          child: RefreshIndicator(
+          child: RefreshIndicator(child: _buildBody(), onRefresh: _loadList),
-              child: SingleChildScrollView(
-                physics: AlwaysScrollableScrollPhysics(),
-                child: _buildBody(),
-              ),
-              onRefresh: _loadList),
         )
       ],
     );
@@ -83,6 +80,24 @@ class _NotificationsScreenState extends State<NotificationsScreen> {
 
   /// Build body
   Widget _buildBody() {
+    if (_status == _Status.ERROR || _list.length == 0)
+      return SingleChildScrollView(
+        physics: AlwaysScrollableScrollPhysics(),
+        child: _buildSingleChildCases(),
+      );
+
+    return ListView(
+      children: _list
+          .map((f) => _NotificationTile(
+                notification: f,
+                usersList: _users,
+                groupsList: _groups,
+              ))
+          .toList(),
+    );
+  }
+
+  Widget _buildSingleChildCases() {
     // In case of error
     if (_status == _Status.ERROR)
       return buildErrorCard(tr("Could not get the list of notifications!"),
@@ -103,3 +118,113 @@ class _NotificationsScreenState extends State<NotificationsScreen> {
       );
   }
 }
+
+class _NotificationTile extends StatelessWidget {
+  final n.Notification notification;
+  final UsersList usersList;
+  final GroupsList groupsList;
+
+  const _NotificationTile({
+    Key key,
+    @required this.notification,
+    @required this.usersList,
+    @required this.groupsList,
+  })  : assert(notification != null),
+        super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    final srcUser = usersList.getUser(notification.fromUser);
+
+    String message = "${srcUser.fullName} ";
+
+    switch (notification.type) {
+      // Comment
+      case n.NotificationType.COMMENT_CREATED:
+        message += tr("posted a comment");
+        break;
+
+      // Friendship requests
+      case n.NotificationType.SENT_FRIEND_REQUEST:
+        message += tr("sent you a friendship request.");
+        break;
+
+      case n.NotificationType.ACCEPTED_FRIEND_REQUEST:
+        message += tr("accepted your friendship request.");
+        break;
+
+      case n.NotificationType.REJECTED_FRIEND_REQUEST:
+        message += tr("rejected your friendship request.");
+        break;
+
+      // Groups membership
+      case n.NotificationType.SENT_GROUP_MEMBERSHIP_INVITATION:
+        message += tr("invited you to join the group");
+        break;
+
+      case n.NotificationType.ACCEPTED_GROUP_MEMBERSHIP_INVITATION:
+        message += tr("accepted his invitation to join the group");
+        break;
+
+      case n.NotificationType.REJECTED_GROUP_MEMBERSHIP_INVITATION:
+        message += tr("rejected his invitation to join the group");
+        break;
+
+      case n.NotificationType.SENT_GROUP_MEMBERSHIP_REQUEST:
+        message += tr("sent a request to join the group");
+        break;
+
+      case n.NotificationType.ACCEPTED_GROUP_MEMBERSHIP_REQUEST:
+        message += tr("accepted you request to join the group");
+        break;
+
+      case n.NotificationType.REJECTED_GROUP_MEMBERSHIP_REQUEST:
+        message += tr("rejected your request to join the group");
+        break;
+
+      // Generic element creation
+      case n.NotificationType.ELEM_CREATED:
+        if (notification.onElemType == n.NotificationElementType.POST)
+          message += tr("created a new post");
+        break;
+
+      case n.NotificationType.ELEM_UPDATED:
+        // Operation not implemented
+        break;
+    }
+
+    // Separator
+    message += " ";
+
+    // Notification target
+
+    // User page
+    if (notification.fromContainerType == n.NotificationElementType.USER_PAGE) {
+      if (notification.fromUser == notification.fromContainerId)
+        message += tr("on his / her page");
+      else
+        message += tr("on %user_name%'s page", args: {
+          "user_name": usersList.getUser(notification.fromContainerId).fullName
+        });
+    }
+
+    // Group page
+    if (notification.fromContainerType ==
+        n.NotificationElementType.GROUP_PAGE) {
+      message += tr("on the group %group%.", args: {
+        "group": groupsList[notification.fromContainerId].displayName
+      });
+    }
+
+    // Group membership
+    if (notification.onElemType == n.NotificationElementType.GROUP_MEMBERSHIP)
+      message += groupsList[notification.onElemId].displayName;
+
+    return ListTile(
+      leading: AccountImageWidget(
+        user: srcUser,
+      ),
+      title: Text(message),
+    );
+  }
+}