Hide entity history and attributes under expandepble card

lib/plugins/spoiler_card.dart

@@ -0,0 +1,44 @@
+import 'package:flutter/material.dart';
+
+class SpoilerCard extends StatefulWidget {
+
+  final String title;
+  final Widget body;
+  final bool isExpanded;
+
+  SpoilerCard({Key key, @required this.title, @required this.body, this.isExpanded: false}) : super(key: key);
+
+  @override
+  _SpoilerCardState createState() => _SpoilerCardState();
+}
+
+class _SpoilerCardState extends State<SpoilerCard> {
+
+  bool _expanded;
+
+  @override
+  void initState() {
+    super.initState();
+    _expanded = widget.isExpanded;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: <Widget>[
+          ListTile(
+            title: Text("${widget.title}"),
+            trailing: Icon(
+              _expanded ? Icons.arrow_drop_up : Icons.arrow_drop_down,
+              size: 20,
+            ),
+            onTap: () => setState((){_expanded = !_expanded;}),
+          ),
+          _expanded ? widget.body : Container(height: 0,)
+        ],
+      ),
+    );
+  }
+}