Error messages

lib/services/dbhelper.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:briessenchecker/services/checklist_provider.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
@@ -185,11 +187,15 @@ class DbHelper {
   }
 
   static Future<void> deleteItemById(int id) async {
-    await _client.from(itemsTableName).delete().eq('id', id);
+    await _client.from(itemsTableName).delete().eq('id', id).onError(_onError);
   }
 
   static Future<void> deleteItemsById(List<int> ids) async {
-    await _client.from(itemsTableName).delete().in_('id', ids);
+    await _client
+        .from(itemsTableName)
+        .delete()
+        .in_('id', ids)
+        .onError(_onError);
   }
 
   static Future<void> deleteChecklistByid(int id) async {
@@ -201,6 +207,12 @@ class DbHelper {
   static Stream<AuthState> get authChangeEventStream =>
       _client.auth.onAuthStateChange;
 
+  static bool isOwner(String id) {
+    return _client.auth.currentSession!.user.id == id;
+  }
+
+  static User? get currentUser => _client.auth.currentUser;
+
   static Stream<List<Map<String, dynamic>>> get checklistChangeEventStream =>
       _client.from(checklistsTableName).stream(primaryKey: ['id']);
 
@@ -245,4 +257,8 @@ class DbHelper {
     }
     return items;
   }
+
+  static FutureOr _onError(Object error, StackTrace stackTrace) {
+    print(error);
+  }
 }

lib/services/scaffold_messenger.dart

@@ -0,0 +1,15 @@
+import 'package:flutter/material.dart';
+
+class Messenger {
+  static void showError(BuildContext context, String error) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        backgroundColor: Theme.of(context).colorScheme.error,
+        content: Text(
+          error,
+          style: TextStyle(color: Theme.of(context).colorScheme.onError),
+        ),
+      ),
+    );
+  }
+}