made tasks dismissible

lib/pages/task_overview_page.dart

@@ -5,6 +5,7 @@ import '../model/extensions/controller_context.dart';
 import '../model/task.dart';
 import '../service/controllers/task_controller.dart';
 import '../service/tools.dart';
+import '../widgets/task_dismissible.dart';
 import 'task_edit_page.dart';
 
 class TaskOverviewPage extends StatefulWidget {
@@ -37,24 +38,28 @@ class _TaskOverviewPageState extends State<TaskOverviewPage> {
   Widget itemBuilder(BuildContext context, int index) {
     final task = tasks.elementAt(index);
 
-    return ListTile(
+    return TaskDismissible(
       key: Key(task.id),
-      title: Text(task.title),
-      subtitle: task.description.isNotEmpty ? Text(task.description) : null,
-      trailing: Checkbox(
-        value: task.isCompleted,
-        onChanged: (isCompleted) => context
-            .controller<TaskController>()
-            .saveTask(task.copyWith(isCompleted: isCompleted)),
+      onDismissedRight: () =>
+          context.controller<TaskController>().deleteTask(task),
+      child: ListTile(
+        title: Text(task.title),
+        subtitle: task.description.isNotEmpty ? Text(task.description) : null,
+        trailing: Checkbox(
+          value: task.isCompleted,
+          onChanged: (isCompleted) => context
+              .controller<TaskController>()
+              .saveTask(task.copyWith(isCompleted: isCompleted)),
+        ),
+        onTap: () async {
+          final result = await onTaskTapped(task);
+          if (result != null && context.mounted) {
+            context.controller<TaskController>().saveTask(
+              result.toTask(id: task.id),
+            );
+          }
+        },
       ),
-      onTap: () async {
-        final result = await onTaskTapped(task);
-        if (result != null && context.mounted) {
-          context.controller<TaskController>().saveTask(
-            result.toTask(id: task.id),
-          );
-        }
-      },
     );
   }