404 causing the pdf viewer to crash on web #2451
Description
Bug description
The syncfusion_flutter_pdfviewer on the web platform is not gracefully handling the 404 error. Instead of just reporting it via onDocumentLoadFailed, it's also letting an unhandled ClientException escape, which can disrupt the app's state.
Steps to reproduce
- pass any url to the screen so it will produce 404
- run on web (chrome)
- get the error
Code sample
Code sample
// lib/screens/pdf_viewer_screen.dart import 'dart:developer'; import 'package:flutter/material.dart'; import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart'; class PdfViewerScreenArgs { PdfViewerScreenArgs({required this.pdfUrl, required this.documentName}); final String documentName; final String pdfUrl; } enum PdfLoadingState { loading, success, error } class PdfViewerScreen extends StatefulWidget { const PdfViewerScreen({super.key, required this.pdfUrl, required this.documentName}); final String documentName; final String pdfUrl; @override State<PdfViewerScreen> createState() => _PdfViewerScreenState(); } class _PdfViewerScreenState extends State<PdfViewerScreen> { String _errorMessage = ''; PdfLoadingState _loadingState = PdfLoadingState.loading; Widget _buildLoadingWidget() { return const ColoredBox( color: Colors.white, child: Center(child: CircularProgressIndicator()), ); } Widget _buildErrorWidget(String message) { return ColoredBox( color: Colors.white, child: Center( child: Padding( padding: const EdgeInsets.all(24.0), child: Column( mainAxisAlignment: MainAxisAlignment.center, children: [ Icon(Icons.cloud_off_rounded, color: Colors.grey.shade500, size: 60), const SizedBox(height: 16), Text('Failed to Load Document', textAlign: TextAlign.center, style: Theme.of(context).textTheme.headlineSmall), const SizedBox(height: 8), Text( message, textAlign: TextAlign.center, style: Theme.of(context).textTheme.bodyLarge?.copyWith(color: Colors.grey.shade700), ), ], ), ), ), ); } @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(title: Text(widget.documentName), backgroundColor: const Color(0xFFF2F8F2)), body: Stack( children: [ SfPdfViewer.network( widget.pdfUrl, key: Key(widget.pdfUrl), onDocumentLoaded: (details) { if (mounted) { setState(() { _loadingState = PdfLoadingState.success; }); } }, onDocumentLoadFailed: (details) { log('PDF Load Failed: ${details.error} - ${details.description}'); if (mounted) { setState(() { _loadingState = PdfLoadingState.error; _errorMessage = 'Document not found or failed to load.'; }); } }, ), if (_loadingState == PdfLoadingState.loading) _buildLoadingWidget(), if (_loadingState == PdfLoadingState.error) _buildErrorWidget(_errorMessage), ], ), ); } }Screenshots or Video
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Stack Traces
Stack Traces
[log] PDF Load Failed: Error - There was an error opening this document. DartError: ClientException: Request to https://dashboard-owwy.wijayalab.uk/api/documents/9/agreement_v1.pdf failed with status 404: ., uri=https://dashboard-owwy.wijayalab.uk/api/documents/9/agreement_v1.pdf dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 274:3 throw_ errors.dart:274 package:http/src/base_client.dart 103:5 [_checkResponseSuccess] base_client.dart:103 package:http/src/base_client.dart 59:5 <fn> base_client.dart:59 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 623:19 <fn> async_patch.dart:623 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 648:23 <fn> async_patch.dart:648 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 594:19 <fn> async_patch.dart:594 dart-sdk/lib/async/zone.dart 1849:54 runUnary zone.dart:1849 dart-sdk/lib/async/future_impl.dart 222:18 handleValue future_impl.dart:222 dart-sdk/lib/async/future_impl.dart 948:44 handleValueCallback future_impl.dart:948 dart-sdk/lib/async/future_impl.dart 977:13 _propagateToListeners future_impl.dart:977 dart-sdk/lib/async/future_impl.dart 720:5 [_completeWithValue] future_impl.dart:720 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 504:7 complete async_patch.dart:504 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 571:12 _asyncReturn async_patch.dart:571 package:http/src/response.dart 66:3 <fn> response.dart:66 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 623:19 <fn> async_patch.dart:623 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 648:23 <fn> async_patch.dart:648 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 594:19 <fn> async_patch.dart:594 dart-sdk/lib/async/zone.dart 1849:54 runUnary zone.dart:1849 dart-sdk/lib/async/future_impl.dart 222:18 handleValue future_impl.dart:222 dart-sdk/lib/async/future_impl.dart 948:44 handleValueCallback future_impl.dart:948 dart-sdk/lib/async/future_impl.dart 977:13 _propagateToListeners future_impl.dart:977 dart-sdk/lib/async/future_impl.dart 720:5 [_completeWithValue] future_impl.dart:720 dart-sdk/lib/async/future_impl.dart 804:7 <fn> future_impl.dart:804 dart-sdk/lib/async/schedule_microtask.dart 40:34 _microtaskLoop schedule_microtask.dart:40 dart-sdk/lib/async/schedule_microtask.dart 49:5 _startMicrotaskLoop schedule_microtask.dart:49 dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear operations.dart:118 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 188:69 <fn> async_patch.dart:188 DartError: ClientException: Request to https://dashboard-owwy.wijayalab.uk/api/documents/9/agreement_v1.pdf failed with status 404: ., uri=https://dashboard-owwy.wijayalab.uk/api/documents/9/agreement_v1.pdf dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 274:3 throw_ errors.dart:274 package:http/src/base_client.dart 103:5 [_checkResponseSuccess] base_client.dart:103 package:http/src/base_client.dart 59:5 <fn> base_client.dart:59 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 623:19 <fn> async_patch.dart:623 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 648:23 <fn> async_patch.dart:648 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 594:19 <fn> async_patch.dart:594 dart-sdk/lib/async/zone.dart 1849:54 runUnary zone.dart:1849 dart-sdk/lib/async/future_impl.dart 222:18 handleValue future_impl.dart:222 dart-sdk/lib/async/future_impl.dart 948:44 handleValueCallback future_impl.dart:948 dart-sdk/lib/async/future_impl.dart 977:13 _propagateToListeners future_impl.dart:977 dart-sdk/lib/async/future_impl.dart 720:5 [_completeWithValue] future_impl.dart:720 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 504:7 complete async_patch.dart:504 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 571:12 _asyncReturn async_patch.dart:571 package:http/src/response.dart 66:3 <fn> response.dart:66 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 623:19 <fn> async_patch.dart:623 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 648:23 <fn> async_patch.dart:648 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 594:19 <fn> async_patch.dart:594 dart-sdk/lib/async/zone.dart 1849:54 runUnary zone.dart:1849 dart-sdk/lib/async/future_impl.dart 222:18 handleValue future_impl.dart:222 dart-sdk/lib/async/future_impl.dart 948:44 handleValueCallback future_impl.dart:948 dart-sdk/lib/async/future_impl.dart 977:13 _propagateToListeners future_impl.dart:977 dart-sdk/lib/async/future_impl.dart 720:5 [_completeWithValue] future_impl.dart:720 dart-sdk/lib/async/future_impl.dart 804:7 <fn> future_impl.dart:804 dart-sdk/lib/async/schedule_microtask.dart 40:34 _microtaskLoop schedule_microtask.dart:40 dart-sdk/lib/async/schedule_microtask.dart 49:5 _startMicrotaskLoop schedule_microtask.dart:49 dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear operations.dart:118 dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 188:69 <fn> async_patch.dart:188On which target platforms have you observed this bug?
Web
Flutter Doctor output
Doctor output
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