UI/UX improvement for the login flow. You can use enter in all text fields and you get better visual cues like red borders on error.

lib/controllers/client_state_controller.dart

@@ -9,14 +9,6 @@ class ClientStateController extends Notifier<ClientState?> {
     state = newState;
   }
 
-  void setHomeServer(String homeserver){
-    state = .new(isInitialized: state?.isInitialized ?? false,
-     isLoggedIn: state?.isLoggedIn ?? false,
-      isVerified: state?.isVerified ?? false,
-       userId: state?.userId,
-        homeserverUrl: homeserver);
-  }
-
   static final provider = NotifierProvider<ClientStateController, ClientState?>(
     ClientStateController.new,
   );

lib/main.dart

@@ -11,7 +11,6 @@ import "package:nexus/controllers/shared_prefs_controller.dart";
 import "package:nexus/helpers/extensions/better_when.dart";
 import "package:nexus/helpers/extensions/scheme_to_theme.dart";
 import "package:nexus/pages/chat_page.dart";
-import "package:nexus/pages/login_page.dart";
 import "package:nexus/pages/select_server_page.dart";
 import "package:nexus/pages/verify_page.dart";
 import "package:nexus/widgets/error_dialog.dart";
@@ -124,10 +123,8 @@ class App extends StatelessWidget {
                       return Loading();
                     }
 
-                    if ((!clientState.isLoggedIn) && (clientState.homeserverUrl == null || clientState.homeserverUrl?.isEmpty == true)) {
+                    if (!clientState.isLoggedIn)  {
                       return SelectServerPage();
-                    } else if(!clientState.isLoggedIn) {
-                      return LoginPage();
                     } else if (!clientState.isVerified) {
                       return VerifyPage();
                     } else {

lib/pages/login_page.dart

@@ -2,67 +2,52 @@ import "package:flutter/material.dart";
 import "package:flutter_hooks/flutter_hooks.dart";
 import "package:hooks_riverpod/hooks_riverpod.dart";
 import "package:nexus/controllers/client_controller.dart";
-import "package:nexus/controllers/client_state_controller.dart";
 import "package:nexus/models/requests/login_request.dart";
 import "package:nexus/widgets/appbar.dart";
 
 class LoginPage extends HookConsumerWidget {
-  const LoginPage({super.key});
+  final Uri homeserver;
+
+  const LoginPage({super.key, required this.homeserver});
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final client = ref.watch(ClientController.provider.notifier);
     final isLoggingIn = useState(false);
-    final homeserverUrl = ref.watch(ClientStateController.provider)?.homeserverUrl;
+    final hasError = useState(false);
+    final userNameFocusNode = useFocusNode();
+    final passwordFocusNode = useFocusNode();
 
-    if(homeserverUrl == null || homeserverUrl.trim().isEmpty) {
-      throw Exception("Homeserver URL must be set for login.");
-    }
+    //This is the safe way to request things directly after page load.
+    useEffect(() {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        userNameFocusNode.requestFocus();
+      });
+      return null;
+    }, []); 
 
     final theme = Theme.of(context);
 
     final username = useTextEditingController();
     final password = useTextEditingController();
 
-    return Scaffold(
-      appBar: Appbar(),
-      body: AlertDialog(
-        title: Text("Login"),
-        content: Column(
-          mainAxisSize: MainAxisSize.min,
-          crossAxisAlignment: CrossAxisAlignment.start,
-          children: [
-            Text(
-              "Enter your login credentials:",
-            ),
-            SizedBox(height: 12),
-            TextField(
-              decoration: InputDecoration(label: Text("Username")),
-              controller: username,
-            ),
-            SizedBox(height: 12),
-            TextField(
-              decoration: InputDecoration(label: Text("Password")),
-              controller: password,
-              obscureText: true,
-            ),          
-          ],
-        ),
-        actions: [
-          TextButton(
-            onPressed: isLoggingIn.value
-                ? null
-                : () async {
+    Future<void> tryLogin() async {
+      if (isLoggingIn.value) return;
       isLoggingIn.value = true;
+      hasError.value = false;
+
       final error = await client.login(
         LoginRequest(
           username: username.text,
           password: password.text,
-                        homeserverUrl: homeserverUrl,
-                      ),
+          homeserverUrl: homeserver.origin
+        )
       );
 
-                    if (error != null && context.mounted) {
+      if (!context.mounted) return;
+
+      if (error != null) {
+        hasError.value = true;
         ScaffoldMessenger.of(context).showSnackBar(
           SnackBar(
             content: Text(
@@ -76,7 +61,89 @@ class LoginPage extends HookConsumerWidget {
         );
         isLoggingIn.value = false;
       }
+      else{
+        Navigator.pop(context);
+      }
+      passwordFocusNode.requestFocus();
+      isLoggingIn.value = false;
+    }
+
+    return Scaffold(
+      appBar: Appbar(
+        leading: IconButton(
+          icon: Icon(Icons.arrow_back),
+          onPressed: () => Navigator.pop(context)
+          ),
+      ),
+      body: AlertDialog(
+        title: Text("Login to ${homeserver.host}"),
+        content: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              "Enter your login credentials:",
+            ),
+            SizedBox(height: 12),
+            TextField(
+              focusNode: userNameFocusNode,
+              textInputAction: TextInputAction.next,
+              onChanged: (newVal) {
+                if (hasError.value) {
+                  hasError.value = false;
+                }
               },
+              decoration: InputDecoration(
+                label: Text("Username"),
+                enabledBorder: OutlineInputBorder(
+                  borderSide: BorderSide(
+                    width: hasError.value ? 4 : 2,
+                    color: hasError.value 
+                    ? theme.colorScheme.error
+                    : theme.colorScheme.primary
+                  ),
+                )
+              ),
+              controller: username,
+            ),
+            SizedBox(height: 12),
+            TextField(
+              focusNode: passwordFocusNode,
+              textInputAction: TextInputAction.done,
+              onSubmitted: (_) => tryLogin(),
+              onChanged: (newVal) {
+                if (hasError.value) {
+                  hasError.value = false;
+                }
+              },
+              selectAllOnFocus: true,
+              decoration: InputDecoration(
+                label: Text("Password"),
+                focusedBorder: OutlineInputBorder(
+                  borderSide: BorderSide(
+                    width: hasError.value ? 4 : 2,
+                    color: hasError.value
+                      ? theme.colorScheme.error
+                      : theme.colorScheme.primary
+                  )
+                ),
+                enabledBorder: OutlineInputBorder(
+                  borderSide: BorderSide(
+                    width: hasError.value ? 4 : 2,
+                    color: hasError.value 
+                    ? theme.colorScheme.error
+                    : theme.colorScheme.primary
+                  ),
+                )
+              ),
+              controller: password,
+              obscureText: true,
+            ),          
+          ],
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => tryLogin(),
             child: Text("Sign In"),
           ),
         ],

lib/pages/select_server_page.dart

@@ -3,9 +3,9 @@ import "package:flutter_hooks/flutter_hooks.dart";
 import "package:flutter_svg/flutter_svg.dart";
 import "package:hooks_riverpod/hooks_riverpod.dart";
 import "package:nexus/controllers/client_controller.dart";
-import "package:nexus/controllers/client_state_controller.dart";
 import "package:nexus/helpers/launch_helper.dart";
 import "package:nexus/models/homeserver.dart";
+import "package:nexus/pages/login_page.dart";
 import "package:nexus/widgets/appbar.dart";
 import "package:nexus/widgets/divider_text.dart";
 import "package:nexus/widgets/loading.dart";
@@ -17,11 +17,11 @@ class SelectServerPage extends HookConsumerWidget {
   Widget build(BuildContext context, WidgetRef ref) {
     final theme = Theme.of(context);
     final client = ref.watch(ClientController.provider.notifier);
-
+    final hasError = useState(false);
     final isLoading = useState(false);
+    final homeserverFocusNode = useFocusNode();
     
     final launch = ref.watch(LaunchHelper.provider).launchUrl;
-
     final homeserverUrl = useTextEditingController();
 
     Future<void> setHomeserver(Uri? newHomeserver) async {
@@ -37,6 +37,7 @@ class SelectServerPage extends HookConsumerWidget {
 
       if (context.mounted) {
         if (newUrl == null) {
+          hasError.value = true;
           ScaffoldMessenger.of(context).showSnackBar(
             SnackBar(
               content: Text(
@@ -48,15 +49,19 @@ class SelectServerPage extends HookConsumerWidget {
           );
         } else {
           homeserverUrl.text = newHomeserver!.origin;
-          ref.watch(ClientStateController.provider.notifier).setHomeServer(newUrl);
+          Navigator.push(context, MaterialPageRoute(builder: (_) => LoginPage(homeserver: Uri.parse(newUrl))));
         }
       }
+
+      homeserverFocusNode.requestFocus();
       isLoading.value = false;
     }
 
     return Scaffold(
       appBar: Appbar(),
-      body: Center(
+      body: isLoading.value 
+        ? const Loading()
+        : Center(
         child: ConstrainedBox(
           constraints: BoxConstraints(maxWidth: 600),
           child: Column(
@@ -90,14 +95,33 @@ class SelectServerPage extends HookConsumerWidget {
                 children: [
                   Expanded(
                     child: TextField(
+                      focusNode: homeserverFocusNode,
+                      textInputAction: TextInputAction.done,
+                      onSubmitted: (_) => setHomeserver(Uri.tryParse(homeserverUrl.text)),
+                      onChanged: (newVal) {
+                        if (hasError.value) {
+                          hasError.value = false;
+                        }
+                      },
                       controller: homeserverUrl,
                       decoration: InputDecoration(
                         labelText: "Homeserver URL (e.g. matrix.org)",
                         hintText: "e.g. matrix.org",
-                        enabledBorder: OutlineInputBorder(
-                          borderSide: BorderSide(color: (homeserverUrl.text.trim().isEmpty)
+                        focusedBorder: OutlineInputBorder(
+                          borderSide: BorderSide(
+                            width: hasError.value ? 4 : 2,
+                            color: hasError.value
                               ? theme.colorScheme.error
-                              : theme.colorScheme.primary)
+                              : theme.colorScheme.primary
+                          )
+                        ),
+                        enabledBorder: OutlineInputBorder(
+                          borderSide: BorderSide(
+                            width: hasError.value ? 4 : 2,
+                            color: hasError.value
+                              ? theme.colorScheme.error 
+                              : theme.colorScheme.primary
+                              )
                         ),
                       ),
                     ),
@@ -174,10 +198,6 @@ class SelectServerPage extends HookConsumerWidget {
                 onPressed: () => launch(Uri.https("servers.joinmatrix.org")),
                 child: Text("See more homeservers..."),
               ),
-              if (isLoading.value)
-                Padding(padding: EdgeInsets.only(top: 32), child: Loading())
-              else 
-                Padding(padding: EdgeInsets.only(top: 12))
             ],
           ),
         ),