Collapsable Emails create a ListTile and upon clicking one it expans and show the html

lib/collapsableEmails.dart

@@ -0,0 +1,130 @@
+import 'dart:js_interop';
+import 'package:web/web.dart' as web;
+import 'package:flutter/material.dart';
+import 'dart:ui_web' as ui;
+import 'api_service.dart';
+import 'structs.dart';
+
+class CollapsableEmails extends StatefulWidget {
+  final List<String> thread; // email id's in the form xyz@gmail.com
+  final List<String> threadHTML;
+
+  CollapsableEmails({required this.thread, required this.threadHTML});
+
+  @override
+  State<CollapsableEmails> createState() => _CollapsableEmailsState();
+}
+
+class _CollapsableEmailsState extends State<CollapsableEmails> {
+  List<String> emailsHTML = []; //html of the emails in the thread
+  // build attachments with the forldar name and id
+  Set<int> _expandedEmails = {}; //open emails
+  List viewtypeIDs = []; //IDs of the viewtypes, order matters
+  List heightOfViewTypes = []; //the height of each viewtype
+
+  @override
+  void initState() {
+    // TODO: implement initState
+    super.initState();
+    _registerViewFactory(widget.threadHTML);
+  }
+
+  void _registerViewFactory(List<String> currentContent) async {
+    // setState(() { //update to do item per item
+    // each item to have itsviewtype ID
+    // is this necessarey here??
+
+    //could just move to collapsable
+
+    for (var emailHTML in widget.threadHTML) {
+      String viewTypeId = 'email-${DateTime.now().millisecondsSinceEpoch}';
+
+      final ghost = web.document.createElement('div') as web.HTMLDivElement
+        ..style.visibility = 'hidden'
+        ..style.position = 'absolute'
+        ..style.width = '100%'
+        ..style.overflow = 'auto'
+        ..innerHTML = emailHTML
+            .toJS; // temporarily index because it has to do all of them
+      web.document.body?.append(ghost);
+      await Future.delayed(Duration(milliseconds: 10));
+
+      final heightOfEmail = ghost.scrollHeight;
+      ghost.remove();
+
+      final HTMLsnippet = web.document.createElement('div')
+          as web.HTMLDivElement
+        ..id = viewTypeId
+        ..innerHTML = emailHTML
+            .toJS; // temporarily index because it has to do all of them
+      HTMLsnippet.style
+        ..width = '100%'
+        ..height = '${heightOfEmail}px'
+        ..overflow = 'auto'
+        ..scrollBehavior = 'smooth';
+
+      ui.platformViewRegistry.registerViewFactory(
+        viewTypeId,
+        (int viewId) => HTMLsnippet,
+      );
+      viewtypeIDs.add(viewTypeId);
+      heightOfViewTypes.add(heightOfEmail);
+    }
+
+    // viewTypeId = 'iframe-${DateTime.now().millisecondsSinceEpoch}';
+    // final emailHTML = web.document.createElement('div') as web.HTMLDivElement
+    //   ..id = viewTypeId
+    //   ..innerHTML = currentContent[0].toJS; // temporarily index because it has to do all of them
+    // emailHTML.style
+    //   ..width = '100%'
+    //   ..height = '100%'
+    //   ..overflow = 'auto'
+    //   ..scrollBehavior = 'smooth';
+
+    // ui.platformViewRegistry.registerViewFactory(
+    //   viewTypeId,
+    //   (int viewId) => emailHTML,
+    // );
+    // });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(children: [
+      Expanded(
+        child: ListView.builder(
+          itemCount: widget.thread.length,
+          itemBuilder: (context, index) {
+            final isExpanded =
+                _expandedEmails.contains(index); //check if email is expanded
+            return Column(
+              children: [
+                ListTile(
+                  title: Text("email $index"),
+                  onTap: () {
+                    setState(() {
+                      if (isExpanded) {
+                        _expandedEmails.remove(index);
+                      } else {
+                        _expandedEmails.add(index);
+                      }
+                    });
+                  },
+                ),
+                if (isExpanded)
+                  // if(viewtypeIDs[index] == null || heightOfViewTypes[index] == null)
+                  //   const SizedBox(height: 100, child: Center(child: CircularProgressIndicator())),
+                  SizedBox(
+                    height:heightOfViewTypes[index].toDouble(),
+                    child: HtmlElementView(
+                        key: UniqueKey(), viewType: viewtypeIDs[index]),
+                  ),
+                Divider(),
+              ],
+            );
+          },
+        ),
+      )
+    ]);
+  }
+}