claude refactorings, flutter best practices, platform dependent changes, general cleanup

lib/widget/file_viewer.dart

@@ -1,16 +1,17 @@
+import 'dart:async';
 import 'dart:io';
 import 'dart:math';
 
+import 'package:file_picker/file_picker.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:open_filex/open_filex.dart';
 import 'package:photo_view/photo_view.dart';
-import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:share_plus/share_plus.dart';
 import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
 
 import '../routing/app_routes.dart';
 import '../state/app/modules/settings/bloc/settings_cubit.dart';
-import '../utils/file_saver.dart';
 import 'info_dialog.dart';
 import 'placeholder_view.dart';
 import 'share_position_origin.dart';
@@ -30,6 +31,55 @@ enum FileViewingActions {
   save
 }
 
+/// Workaround for a Syncfusion PDF viewer race: SfPdfViewer's internal
+/// LayoutBuilder calls `localToGlobal` during build, which asserts when an
+/// ancestor RenderTransform (from the page-push animation) is still mid-layout.
+/// We wait for the route's enter animation to complete before mounting it.
+class _DeferredPdfViewer extends StatefulWidget {
+  const _DeferredPdfViewer({required this.path});
+  final String path;
+
+  @override
+  State<_DeferredPdfViewer> createState() => _DeferredPdfViewerState();
+}
+
+class _DeferredPdfViewerState extends State<_DeferredPdfViewer> {
+  bool _ready = false;
+  Animation<double>? _routeAnimation;
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    if (_ready || _routeAnimation != null) return;
+    final animation = ModalRoute.of(context)?.animation;
+    if (animation == null || animation.isCompleted) {
+      _ready = true;
+      return;
+    }
+    _routeAnimation = animation..addStatusListener(_onAnimationStatus);
+  }
+
+  void _onAnimationStatus(AnimationStatus status) {
+    if (status == AnimationStatus.completed && mounted) {
+      setState(() => _ready = true);
+    }
+  }
+
+  @override
+  void dispose() {
+    _routeAnimation?.removeStatusListener(_onAnimationStatus);
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (!_ready) {
+      return const Center(child: CircularProgressIndicator());
+    }
+    return SfPdfViewer.file(File(widget.path));
+  }
+}
+
 class _FileViewerState extends State<FileViewer> {
   PhotoViewController photoViewController = PhotoViewController();
 
@@ -44,7 +94,7 @@ class _FileViewerState extends State<FileViewer> {
 
   @override
   Widget build(BuildContext context) {
-    AppBar appbar({List actions = const []}) => AppBar(
+    AppBar appbar({List<Widget> actions = const []}) => AppBar(
         title: Text(widget.path.split('/').last),
         actions: [
           ...actions,
@@ -55,17 +105,26 @@ class _FileViewerState extends State<FileViewer> {
                   AppRoutes.openFileViewer(context, widget.path, openExternal: true);
                   break;
                 case FileViewingActions.share:
-                  SharePlus.instance.share(
-                      ShareParams(
-                          files: [XFile(widget.path)],
-                          sharePositionOrigin: SharePositionOrigin.get(context)
-                      )
-                  );
+                  unawaited(SharePlus.instance.share(
+                    ShareParams(
+                      files: [XFile(widget.path)],
+                      sharePositionOrigin: SharePositionOrigin.get(context),
+                    ),
+                  ));
                   break;
                 case FileViewingActions.save:
-                  await FileSaver.writeBytes(await File(widget.path).readAsBytes(), widget.path.split('/').last);
-                  if(!context.mounted) return;
-                  InfoDialog.show(context, 'Die Datei wurde im Downloads Ordner gespeichert.');
+                  try {
+                    final bytes = await File(widget.path).readAsBytes();
+                    final saved = await FilePicker.saveFile(
+                      fileName: widget.path.split('/').last,
+                      bytes: bytes,
+                    );
+                    if (!context.mounted) return;
+                    if (saved != null) InfoDialog.show(context, 'Datei gespeichert.');
+                  } on Object catch (e) {
+                    if (!context.mounted) return;
+                    InfoDialog.show(context, 'Speichern fehlgeschlagen: $e');
+                  }
                   break;
               }
             },
@@ -86,7 +145,7 @@ class _FileViewerState extends State<FileViewer> {
                   dense: true,
                 ),
               ),
-              if(Platform.isAndroid) const PopupMenuItem(
+              const PopupMenuItem(
                 value: FileViewingActions.save,
                 child: ListTile(
                   leading: Icon(Icons.save_alt_outlined),
@@ -129,9 +188,7 @@ class _FileViewerState extends State<FileViewer> {
       case 'pdf':
         return Scaffold(
           appBar: appbar(),
-          body: SfPdfViewer.file(
-            File(widget.path),
-          ),
+          body: _DeferredPdfViewer(path: widget.path),
         );
 
       default: