deletable lists

lib/box_checker.dart

@@ -53,6 +53,10 @@ class _MainListPageState extends State<MainListPage> {
     });
   }
 
+  Future<void> _removeList(data.List list) async {
+    DBHelper.dbHelper.deleteList(list);
+  }
+
   @override
   void initState() {
     _loadData(data.Page.lists);
@@ -84,7 +88,55 @@ class _MainListPageState extends State<MainListPage> {
             child: ListView.builder(
                 itemCount: lists.length,
                 itemBuilder: (context, index) {
-                  return Card(
+                  return Dismissible(
+                    direction: DismissDirection.startToEnd,
+                    key: Key(lists[index].id.toString()),
+                    background: Card(
+                      color: Colors.red,
+                      child: Row(
+                        children: const [
+                          Padding(
+                            padding: EdgeInsets.all(10),
+                            child: Icon(Icons.delete),
+                          ),
+                        ],
+                      ),
+                    ),
+                    confirmDismiss: (direction) async {
+                      if (direction != DismissDirection.startToEnd) {
+                        return false;
+                      }
+
+                      showDialog(
+                          context: context,
+                          builder: (context) {
+                            return AlertDialog(
+                              title: const Text('Are you sure?'),
+                              content: const Text(
+                                  'You are about to delete this permently'),
+                              actions: [
+                                TextButton(
+                                    onPressed: () =>
+                                        Navigator.pop(context, false),
+                                    child: const Text('Cancel')),
+                                TextButton(
+                                    onPressed: () =>
+                                        Navigator.pop(context, true),
+                                    child: const Text('OK')),
+                              ],
+                            );
+                          }).then((value) {
+                        if (value) {
+                          setState(() {
+                            _removeList(lists[index]);
+                            lists.removeAt(index);
+                          });
+                        }
+
+                        return value;
+                      });
+                    },
+                    child: Card(
                       child: ListTile(
                         onTap: () {
                           Navigator.push(
@@ -96,6 +148,7 @@ class _MainListPageState extends State<MainListPage> {
                         title: Text(lists[index].name),
                         subtitle: Text(lists[index].id.toString()),
                       ),
+                    ),
                   );
                 })),
         bottomNavigationBar: BottomNavigationBar(

lib/db_helper.dart

@@ -77,6 +77,12 @@ class DBHelper {
     return db.insert("List", l.toMap());
   }
 
+  Future<int> deleteList(data.List l) async {
+    Database db = await database;
+
+    return db.delete("List", where: 'id = ?', whereArgs: [l.id]);
+  }
+
   Future<int> insertItem(data.Check item) async {
     Database db = await database;