fix error where app tried to set state off a nonexistant widget

lib/global.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
 import 'package:loris/business_logic/settings.dart';
-import './pages/timeline/timeline.dart' as tl;
 
 const String name = "loris";
 const String version = "v0.1 'is this thing on'";
@@ -8,8 +7,6 @@ const String useragent = "$name/$version";
 const String website = "https://git.kittycat.homes/zoe/loris";
 const String legalese = "todo";
 
-final GlobalKey<tl.TimelineState> tlKey = GlobalKey<tl.TimelineState>();
-
 const Map<String, String> defaultHeaders = {
   "User-Agent": useragent,
   "accept": "application/json",

lib/pages/timeline/timeline.dart

@@ -41,40 +41,42 @@ class TimelineState extends State<Timeline> with AutomaticKeepAliveClientMixin {
 
     final models = await tl.getTimelineFromServer(
         oldestId, selectedId, selectedTimelineType);
-    setState(() {
-      children.removeWhere((element) {
-        return element.runtimeType != Thread;
+
+    if (mounted) {
+      setState(() {
+        children.removeWhere((element) {
+          return element.runtimeType != Thread;
+        });
+        List<Thread> threads = [];
+
+        for (int i = 0; i < models.length; i++) {
+          threads.add(Thread(model: models[i]));
+        }
+
+        if (models.isNotEmpty) {
+          oldestId = models.last.posts.last.id;
+        }
+        children.addAll(threads);
+        children.add(
+          Row(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              TextButton.icon(
+                onPressed: () {
+                  fetchMore();
+                },
+                icon: const Icon(Icons.more_horiz),
+                label: Text(
+                  "load-more".i18n(),
+                ),
+              )
+            ],
+          ),
+        );
+        children.add(const LoadingBox());
+        loading = false;
       });
-
-      List<Thread> threads = [];
-
-      for (int i = 0; i < models.length; i++) {
-        threads.add(Thread(model: models[i]));
-      }
-
-      if (models.isNotEmpty) {
-        oldestId = models.last.posts.last.id;
-      }
-      children.addAll(threads);
-      children.add(
-        Row(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: [
-            TextButton.icon(
-              onPressed: () {
-                fetchMore();
-              },
-              icon: const Icon(Icons.more_horiz),
-              label: Text(
-                "load-more".i18n(),
-              ),
-            )
-          ],
-        ),
-      );
-      children.add(const LoadingBox());
-      loading = false;
-    });
+    }
   }
 
   @override
@@ -94,6 +96,7 @@ class TimelineState extends State<Timeline> with AutomaticKeepAliveClientMixin {
         child: Text(global.settings!.identities.keys.toList()[i]),
       ));
     }
+    selectedId = global.settings!.activeIdentity;
     return Column(
       children: [
         Container(
@@ -110,7 +113,7 @@ class TimelineState extends State<Timeline> with AutomaticKeepAliveClientMixin {
               DropdownButton(
                 value: selectedId,
                 items: identities,
-                onChanged: (dynamic value) {
+                onChanged: (dynamic value) async {
                   setState(() {
                     selectedId = value ?? global.settings!.activeIdentity;
                     global.settings!.saveActiveIdentity(selectedId);

lib/partials/main_scaffold.dart

@@ -7,6 +7,7 @@ import 'package:loris/pages/timeline/timeline.dart';
 import 'package:loris/pages/settings/settings.dart';
 import '../global.dart' as global;
 import '../business_logic/websocket.dart' as websocket;
+import '../pages/timeline/timeline.dart' as tl;
 
 class MainScaffold extends StatefulWidget {
   const MainScaffold({Key? key}) : super(key: key);
@@ -20,10 +21,11 @@ class _MainScaffoldState extends State<MainScaffold> {
 
   @override
   Widget build(BuildContext context) {
+    final GlobalKey<tl.TimelineState> tlKey = GlobalKey<tl.TimelineState>();
     websocket.reloadWebsockets();
     final screens = [
       Timeline(
-        key: global.tlKey,
+        key: tlKey,
       ),
       chat(context),
       notifications(context),