neon: refactor page loading

packages/neon/neon/lib/src/pages/home.dart

@@ -98,56 +98,54 @@ class _HomePageState extends State<HomePage> {
   }
 
   @override
-  Widget build(final BuildContext context) => ResultBuilder<Iterable<AppImplementation>>.behaviorSubject(
-        stream: _appsBloc.appImplementations,
-        builder: (final context, final appImplementations) => StreamBuilder<AppImplementation>(
-          stream: _appsBloc.activeApp,
-          builder: (final context, final activeAppSnapshot) => OptionBuilder<NavigationMode>(
-            option: _globalOptions.navigationMode,
-            builder: (final context, final navigationMode) {
-              final drawerAlwaysVisible = navigationMode == NavigationMode.drawerAlwaysVisible;
-
+  Widget build(final BuildContext context) {
     const drawer = NeonDrawer();
     const appBar = NeonAppBar();
 
-              Widget body = Builder(
-                builder: (final context) => Column(
-                  children: [
-                    if (appImplementations.hasData) ...[
-                      if (appImplementations.requireData.isEmpty) ...[
-                        Expanded(
-                          child: Center(
+    final appView = ResultBuilder<Iterable<AppImplementation>>.behaviorSubject(
+      stream: _appsBloc.appImplementations,
+      builder: (final context, final appImplementations) {
+        if (!appImplementations.hasData) {
+          return const SizedBox();
+        }
+
+        if (appImplementations.requireData.isEmpty) {
+          return Center(
             child: Text(
               AppLocalizations.of(context).errorNoCompatibleNextcloudAppsFound,
               textAlign: TextAlign.center,
             ),
-                          ),
-                        ),
-                      ] else ...[
-                        if (activeAppSnapshot.hasData) ...[
-                          Expanded(
-                            child: activeAppSnapshot.requireData.page,
-                          ),
-                        ],
-                      ],
-                    ],
-                  ],
-                ),
           );
+        }
 
-              body = MultiProvider(
-                providers: _appsBloc.appBlocProviders,
-                child: Scaffold(
+        return StreamBuilder<AppImplementation>(
+          stream: _appsBloc.activeApp,
+          builder: (final context, final activeAppIDSnapshot) {
+            if (!activeAppIDSnapshot.hasData) {
+              return const SizedBox();
+            }
+
+            return activeAppIDSnapshot.requireData.page;
+          },
+        );
+      },
+    );
+
+    final body = OptionBuilder<NavigationMode>(
+      option: _globalOptions.navigationMode,
+      builder: (final context, final navigationMode) {
+        final drawerAlwaysVisible = navigationMode == NavigationMode.drawerAlwaysVisible;
+
+        final body = Scaffold(
           key: _scaffoldKey,
           resizeToAvoidBottomInset: false,
           drawer: !drawerAlwaysVisible ? drawer : null,
           appBar: appBar,
-                  body: body,
-                ),
+          body: appView,
         );
 
         if (drawerAlwaysVisible) {
-                body = Row(
+          return Row(
             children: [
               drawer,
               Expanded(
@@ -157,6 +155,10 @@ class _HomePageState extends State<HomePage> {
           );
         }
 
+        return body;
+      },
+    );
+
     return WillPopScope(
       onWillPop: () async {
         if (_scaffoldKey.currentState!.isDrawerOpen) {
@@ -167,10 +169,10 @@ class _HomePageState extends State<HomePage> {
         _scaffoldKey.currentState!.openDrawer();
         return false;
       },
+      child: MultiProvider(
+        providers: _appsBloc.appBlocProviders,
         child: body,
-              );
-            },
-          ),
       ),
     );
   }
+}