Added the ability to add a user to a group when subscribing.

This extends the subscribe button (currently used in the search and
profile screens) to allow selecting one or more groups to add the
user to.

It also includes a new library (multi_select_flutter) which can be
used in other places where we have a list of checkboxes.

Fixes #114.

fastlane/metadata/android/en-US/changelogs/next.txt

@@ -1,3 +1,4 @@
+- Added the ability to add a user to a group when subscribing
 - Improved the layout of the video player, making it possible to seek on narrower screens
 - Fixed poll colors hiding text in light mode
 - Fixed tweets not opening when a profile, search, or tweet screen is already open

lib/home_model.dart

@@ -87,6 +87,25 @@ class HomeModel extends ChangeNotifier {
         .toList(growable: false);
   }
 
+  Future saveUserGroupMembership(int user, List<String> memberships) async {
+    var database = await Repository.writable();
+
+    var batch = database.batch();
+
+    // First, clear all the memberships for the user
+    batch.delete(TABLE_SUBSCRIPTION_GROUP_MEMBER, where: 'profile_id = ?', whereArgs: [user]);
+
+    // Then add all the new memberships
+    for (var group in memberships) {
+      batch.insert(TABLE_SUBSCRIPTION_GROUP_MEMBER, {
+        'group_id': group,
+        'profile_id': user
+      });
+    }
+
+    await batch.commit();
+  }
+
   Future<SubscriptionGroupEdit> loadSubscriptionGroupEdit(String? id) async {
     var database = await Repository.readOnly();
 

lib/user.dart

@@ -1,5 +1,10 @@
 import 'package:extended_image/extended_image.dart';
 import 'package:flutter/material.dart';
+import 'package:fritter/database/entities.dart';
+import 'package:fritter/home_model.dart';
+import 'package:fritter/ui/errors.dart';
+import 'package:fritter/ui/futures.dart';
+import 'package:multi_select_flutter/multi_select_flutter.dart';
 import 'package:sqflite/sqflite.dart';
 
 import 'database/repository.dart';
@@ -55,6 +60,8 @@ class UserTile extends StatelessWidget {
 
 }
 
+// TODO: This is a very stateful widget. It can probably be extracted out into a
+// model so this widget can become a little simpler.
 class FollowButton extends StatefulWidget {
   final String id;
   final String name;
@@ -98,6 +105,36 @@ class _FollowButtonState extends State<FollowButton> {
     return result.first.values.first == 1;
   }
 
+  Future<List<SubscriptionGroup>> listGroups() async {
+    return await HomeModel().listSubscriptionGroups(orderBy: 'name', orderByAscending: true);
+  }
+
+  Future<List<String>> listGroupsForUser(int id) async {
+    Database database = await Repository.readOnly();
+
+    return (await database.query(TABLE_SUBSCRIPTION_GROUP_MEMBER, columns: ['group_id'], where: 'profile_id = ?', whereArgs: [id]))
+      .map((e) => e['group_id'] as String)
+      .toList(growable: false);
+  }
+
+  Future toggleSubscribe(int id, bool currentlyFollowed) async {
+    Database database = await Repository.writable();
+
+    if (currentlyFollowed) {
+      await database.delete(TABLE_SUBSCRIPTION, where: 'id = ?', whereArgs: [id]);
+      await database.delete(TABLE_SUBSCRIPTION_GROUP_MEMBER, where: 'profile_id = ?', whereArgs: [id]);
+    } else {
+      await database.insert(TABLE_SUBSCRIPTION, {
+        'id': id,
+        'screen_name': widget.screenName,
+        'name': widget.name,
+        'profile_image_url_https': widget.imageUri
+      });
+    }
+
+    await fetchFollowed();
+  }
+
   @override
   Widget build(BuildContext context) {
     var id = int.parse(widget.id);
@@ -111,21 +148,66 @@ class _FollowButtonState extends State<FollowButton> {
         ? Icon(Icons.person_remove)
         : Icon(Icons.person_add);
 
-    return IconButton(icon: icon, onPressed: () async {
-      Database database = await Repository.writable();
-
-      if (followed) {
-        await database.delete(TABLE_SUBSCRIPTION, where: 'id = ?', whereArgs: [id]);
-      } else {
-        await database.insert(TABLE_SUBSCRIPTION, {
-          'id': id,
-          'screen_name': widget.screenName,
-          'name': widget.name,
-          'profile_image_url_https': widget.imageUri
-        });
-      }
-
-      await fetchFollowed();
-    });
+    var text = followed
+        ? 'Unsubscribe'
+        : 'Subscribe';
+
+    return PopupMenuButton<String>(
+      icon: icon,
+      itemBuilder: (context) => [
+        PopupMenuItem(child: Text(text), value: 'toggle_subscribe'),
+        PopupMenuItem(child: Text('Add to group'), value: 'add_to_group'),
+      ],
+      onSelected: (value) async {
+        switch (value) {
+          case 'add_to_group':
+            showDialog(context: context, builder: (context) {
+              var futures = [
+                listGroups(),
+                listGroupsForUser(id)
+              ];
+
+              // TODO: Add types
+              return FutureBuilderWrapper<List<dynamic>>(
+                future: Future.wait(futures),
+                onError: (error, stackTrace) => FullPageErrorWidget(
+                  error: error,
+                  stackTrace: stackTrace,
+                  prefix: 'Unable to load subscription groups',
+                ),
+                onReady: (data) {
+                  var groups = data[0] as List<SubscriptionGroup>;
+                  var existing = data[1] as List<String>;
+
+                  return  MultiSelectDialog(
+                    itemsTextStyle: Theme.of(context).primaryTextTheme.bodyText1,
+                    selectedColor: Theme.of(context).accentColor,
+                    unselectedColor: Theme.of(context).brightness == Brightness.dark
+                      ? Colors.white70
+                      : Colors.black54,
+                    selectedItemsTextStyle: Theme.of(context).primaryTextTheme.bodyText1,
+                    items: groups.map((e) => MultiSelectItem(e.id, e.name)).toList(),
+                    initialValue: existing,
+                    onConfirm: (List<String> memberships) async {
+                      // If we're not currently following the user, follow them first
+                      if (followed == false) {
+                        await toggleSubscribe(id, followed);
+                      }
+
+                      // Then add them to all the selected groups
+                      await HomeModel()
+                          .saveUserGroupMembership(id, memberships);
+                    },
+                  );
+                },
+              );
+            });
+            break;
+          case 'toggle_subscribe':
+            await toggleSubscribe(id, followed);
+            break;
+        }
+      },
+    );
   }
 }

pubspec.lock

@@ -396,6 +396,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.0"
+  multi_select_flutter:
+    dependency: "direct main"
+    description:
+      name: multi_select_flutter
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "4.0.0"
   nested:
     dependency: transitive
     description:

pubspec.yaml

@@ -44,6 +44,7 @@ dependencies:
   http: ^0.13.1
   infinite_scroll_pagination: ^3.0.1
   intl: ^0.17.0
+  multi_select_flutter: ^4.0.0
   package_info: ^2.0.0
   pref: ^2.0.2
   quiver: ^3.0.1