Add vendor activities

lib/ui/vendor/view/vendor_view_activity.dart

@@ -0,0 +1,48 @@
+// Flutter imports:
+import 'package:flutter/material.dart';
+
+// Project imports:
+import 'package:invoiceninja_flutter/ui/app/lists/activity_list_tile.dart';
+import 'package:invoiceninja_flutter/ui/app/lists/list_divider.dart';
+import 'package:invoiceninja_flutter/ui/app/loading_indicator.dart';
+import 'package:invoiceninja_flutter/ui/app/scrollable_listview.dart';
+import 'package:invoiceninja_flutter/ui/vendor/view/vendor_view_vm.dart';
+
+class VendorViewActivity extends StatefulWidget {
+  const VendorViewActivity({Key key, this.viewModel}) : super(key: key);
+
+  final VendorViewVM viewModel;
+
+  @override
+  _VendorViewActivityState createState() => _VendorViewActivityState();
+}
+
+class _VendorViewActivityState extends State<VendorViewActivity> {
+  @override
+  void didChangeDependencies() {
+    if (widget.viewModel.vendor.isStale) {
+      widget.viewModel.onRefreshed(context);
+    }
+    super.didChangeDependencies();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final vendor = widget.viewModel.vendor;
+    final activities = vendor.activities;
+
+    if (!vendor.isLoaded) {
+      return LoadingIndicator();
+    }
+
+    return ScrollableListViewBuilder(
+      itemCount: activities.length,
+      padding: const EdgeInsets.symmetric(vertical: 16),
+      separatorBuilder: (context, index) => ListDivider(),
+      itemBuilder: (BuildContext context, index) {
+        final activity = activities[index];
+        return ActivityListTile(activity: activity);
+      },
+    );
+  }
+}