added cargo files

PinePods-0.8.2/mobile/lib/ui/widgets/placeholder_builder.dart

@@ -0,0 +1,25 @@
+// Copyright 2020 Ben Hills and the project contributors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+import 'package:flutter/material.dart';
+
+class PlaceholderBuilder extends InheritedWidget {
+  final WidgetBuilder Function() builder;
+  final WidgetBuilder Function() errorBuilder;
+
+  const PlaceholderBuilder({
+    super.key,
+    required this.builder,
+    required this.errorBuilder,
+    required super.child,
+  });
+
+  static PlaceholderBuilder? of(BuildContext context) {
+    return context.dependOnInheritedWidgetOfExactType<PlaceholderBuilder>();
+  }
+
+  @override
+  bool updateShouldNotify(PlaceholderBuilder oldWidget) {
+    return builder != oldWidget.builder || errorBuilder != oldWidget.errorBuilder;
+  }
+}