Change `urlLanucher` signature to include `instanceUrl`

lib/pages/communities_list.dart

@@ -31,7 +31,10 @@ class CommunitiesListPage extends StatelessWidget {
             subtitle: communities[i].description != null
                 ? Opacity(
                     opacity: 0.5,
-                    child: MarkdownText(communities[i].description),
+                    child: MarkdownText(
+                      communities[i].description,
+                      instanceUrl: communities[i].instanceUrl,
+                    ),
                   )
                 : null,
             onTap: () => goToCommunity.byId(

lib/pages/community.dart

@@ -433,7 +433,8 @@ class _AboutTab extends StatelessWidget {
         if (community.description != null) ...[
           Padding(
             padding: const EdgeInsets.symmetric(horizontal: 15),
-            child: MarkdownText(community.description),
+            child: MarkdownText(community.description,
+                instanceUrl: community.instanceUrl),
           ),
           _Divider(),
         ],

lib/pages/instance.dart

@@ -208,7 +208,9 @@ class InstancePage extends HookWidget {
                   Center(child: Text('comments go here')),
                 ],
               ),
-              _AboutTab(site, communitiesFuture: communitiesFuture),
+              _AboutTab(site,
+                  communitiesFuture: communitiesFuture,
+                  instanceUrl: instanceUrl),
             ],
           ),
         ),
@@ -241,9 +243,12 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
 class _AboutTab extends HookWidget {
   final FullSiteView site;
   final Future<List<CommunityView>> communitiesFuture;
+  final String instanceUrl;
 
-  const _AboutTab(this.site, {@required this.communitiesFuture})
+  const _AboutTab(this.site,
-      : assert(communitiesFuture != null);
+      {@required this.communitiesFuture, @required this.instanceUrl})
+      : assert(communitiesFuture != null),
+        assert(instanceUrl != null);
 
   void goToUser(int id) {
     print('GO TO USER $id');
@@ -280,7 +285,10 @@ class _AboutTab extends HookWidget {
           children: [
             Padding(
               padding: const EdgeInsets.symmetric(horizontal: 15, vertical: 15),
-              child: MarkdownText(site.site.description),
+              child: MarkdownText(
+                site.site.description,
+                instanceUrl: instanceUrl,
+              ),
             ),
             _Divider(),
             SizedBox(
@@ -356,7 +364,9 @@ class _AboutTab extends HookWidget {
                           e.preferredUsername.isEmpty)
                       ? '@${e.name}'
                       : e.preferredUsername),
-                  subtitle: e.bio != null ? MarkdownText(e.bio) : null,
+                  subtitle: e.bio != null
+                      ? MarkdownText(e.bio, instanceUrl: instanceUrl)
+                      : null,
                   onTap: () => goToUser(e.id),
                   leading: e.avatar != null
                       ? CachedNetworkImage(

lib/pages/users_list.dart

@@ -2,6 +2,7 @@ import 'package:cached_network_image/cached_network_image.dart';
 import 'package:flutter/material.dart';
 import 'package:lemmy_api_client/lemmy_api_client.dart';
 
+import '../util/api_extensions.dart';
 import '../widgets/markdown_text.dart';
 
 class UsersListPage extends StatelessWidget {
@@ -35,7 +36,10 @@ class UsersListPage extends StatelessWidget {
             subtitle: users[i].bio != null
                 ? Opacity(
                     opacity: 0.5,
-                    child: MarkdownText(users[i].bio),
+                    child: MarkdownText(
+                      users[i].bio,
+                      instanceUrl: users[i].instanceUrl,
+                    ),
                   )
                 : null,
             onTap: () => goToUser(context, users[i].id),

lib/widgets/comment.dart

@@ -169,7 +169,9 @@ class Comment extends StatelessWidget {
           style: TextStyle(fontStyle: FontStyle.italic),
         ));
       } else {
-        return Flexible(child: MarkdownText(commentTree.comment.content));
+        return Flexible(
+            child: MarkdownText(commentTree.comment.content,
+                instanceUrl: commentTree.comment.instanceUrl));
       }
     }();
 

lib/widgets/markdown_text.dart

@@ -6,20 +6,22 @@ import 'package:markdown/markdown.dart' as md;
 import '../url_launcher.dart';
 
 class MarkdownText extends StatelessWidget {
+  final String instanceUrl;
   final String text;
-  MarkdownText(this.text);
+  MarkdownText(this.text, {@required this.instanceUrl})
+      : assert(instanceUrl != null);
 
   @override
   Widget build(BuildContext context) => MarkdownBody(
         data: text,
         extensionSet: md.ExtensionSet.gitHubWeb,
         onTapLink: (href) {
-          urlLauncher(context, href)
+          urlLauncher(context: context, url: href, instanceUrl: instanceUrl)
               .catchError((e) => Scaffold.of(context).showSnackBar(SnackBar(
                     content: Row(
                       children: [
                         Icon(Icons.warning),
-                        Text("couldn't open link"),
+                        Text("couldn't open link, ${e.toString()}"),
                       ],
                     ),
                   )));

lib/widgets/post.dart

@@ -144,7 +144,8 @@ class Post extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
-    void _openLink() => urlLauncher(context, post.url);
+    void _openLink() =>
+        urlLauncher(context: context, url: post.url, instanceUrl: instanceUrl);
 
     final urlDomain = () {
       if (post.url == null) return null;
@@ -437,7 +438,7 @@ class Post extends StatelessWidget {
             if (post.body != null)
               Padding(
                   padding: const EdgeInsets.all(10),
-                  child: MarkdownText(post.body)),
+                  child: MarkdownText(post.body, instanceUrl: instanceUrl)),
             actions(),
           ],
         ),