add events to ui

Signed-off-by: fufesou <shuanglongchen@yeah.net>

flutter/lib/plugin/widget.dart

@@ -0,0 +1,17 @@
+import 'package:flutter/material.dart';
+
+final Map<String, PluginWidget> pluginWidgets = {};
+
+class PluginWidget {
+  final String id;
+  final String name;
+  final String location;
+  final Widget widget;
+
+  PluginWidget({
+    required this.id,
+    required this.name,
+    required this.location,
+    required this.widget,
+  });
+}