Add offline dialog (#954)

* feat: show error dialog when attempting to download resources while offline

* formatting

* use state.mounted instead of context.mounted to check if the screen is in the widget tree

* Reset the resources UI without clearing cache

* chore: removed unused import

* Catch any exception instead of SocketException only

* Format Dart files

---------

Co-authored-by: Anh <[email protected]>

Author: farook-edev

flutter/lib/benchmark/state.dart

@@ -143,15 +143,21 @@ class BenchmarkState extends ChangeNotifier {
       modes: [taskRunner.perfMode, taskRunner.accuracyMode],
       benchmarks: benchmarks,
     );
-    await resourceManager.handleResources(
-      resources,
-      needToPurgeCache,
-      downloadMissing,
-    );
-    print('Finished loading resources with downloadMissing=$downloadMissing');
-    error = null;
-    stackTrace = null;
-    taskConfigFailedToLoad = false;
+    try {
+      await resourceManager.handleResources(
+        resources,
+        needToPurgeCache,
+        downloadMissing,
+      );
+      print('Finished loading resources with downloadMissing=$downloadMissing');
+      error = null;
+      stackTrace = null;
+      taskConfigFailedToLoad = false;
+    } catch (e, s) {
+      print('Could not load resources due to error: $e');
+      error = e;
+      stackTrace = s;
+    }
     await Wakelock.disable();
   }
 

flutter/lib/l10n/app_en.arb

@@ -95,7 +95,6 @@
   "dialogContentChecksumError": "The following files failed checksum validation:",
   "dialogContentNoSelectedBenchmarkError": "Please select at least one benchmark.",
 
-
   "benchModePerformanceOnly": "Performance Only",
   "benchModeAccuracyOnly": "Accuracy Only",
   "benchModeSubmissionRun": "Submission Run",

flutter/lib/resources/resource_manager.dart

@@ -100,42 +100,47 @@ class ResourceManager {
     _loadingProgress = 0.001;
     _done = false;
     _onUpdate();
-
-    var internetResources = <Resource>[];
-    for (final resource in resources) {
-      if (resource.path.startsWith(_dataPrefix)) continue;
-      if (isInternetResource(resource.path)) {
-        internetResources.add(resource);
-        continue;
+    try {
+      var internetResources = <Resource>[];
+      for (final resource in resources) {
+        if (resource.path.startsWith(_dataPrefix)) continue;
+        if (isInternetResource(resource.path)) {
+          internetResources.add(resource);
+          continue;
+        }
+        throw 'forbidden path: ${resource.path} (only http://, https:// and local:// resources are allowed)';
       }
-      throw 'forbidden path: ${resource.path} (only http://, https:// and local:// resources are allowed)';
-    }
 
-    final internetPaths = internetResources.map((e) => e.path).toList();
-    await cacheManager.cache(
-      internetPaths,
-      (double currentProgress, String currentPath) {
-        _loadingProgress = currentProgress;
-        _loadingPath = currentPath;
-        _onUpdate();
-      },
-      purgeOldCache,
-      downloadMissing,
-    );
-
-    final checksumFailed = await validateResourcesChecksum(resources);
-    if (checksumFailed.isNotEmpty) {
-      final mismatchedPaths = checksumFailed.map((e) => '\n${e.path}').join();
-      throw 'Checksum validation failed for: $mismatchedPaths';
-    }
+      final internetPaths = internetResources.map((e) => e.path).toList();
+      try {
+        await cacheManager.cache(
+          internetPaths,
+          (double currentProgress, String currentPath) {
+            _loadingProgress = currentProgress;
+            _loadingPath = currentPath;
+            _onUpdate();
+          },
+          purgeOldCache,
+          downloadMissing,
+        );
+      } on SocketException {
+        throw 'A network error has occurred. Please make sure you are connected to the internet.';
+      }
 
-    // delete downloaded archives to free up disk space
-    await cacheManager.deleteArchives(internetPaths);
+      final checksumFailed = await validateResourcesChecksum(resources);
+      if (checksumFailed.isNotEmpty) {
+        final mismatchedPaths = checksumFailed.map((e) => '\n${e.path}').join();
+        throw 'Checksum validation failed for: $mismatchedPaths';
+      }
 
-    _loadingPath = '';
-    _loadingProgress = 1.0;
-    _done = true;
-    _onUpdate();
+      // delete downloaded archives to free up disk space
+      await cacheManager.deleteArchives(internetPaths);
+    } finally {
+      _loadingPath = '';
+      _loadingProgress = 1.0;
+      _done = true;
+      _onUpdate();
+    }
   }
 
   static Future<String> getApplicationDirectory() async {

flutter/lib/ui/settings/resources_screen.dart

@@ -9,6 +9,7 @@ import 'package:mlperfbench/benchmark/state.dart';
 import 'package:mlperfbench/localizations/app_localizations.dart';
 import 'package:mlperfbench/store.dart';
 import 'package:mlperfbench/ui/confirm_dialog.dart';
+import 'package:mlperfbench/ui/error_dialog.dart';
 
 class ResourcesScreen extends StatefulWidget {
   const ResourcesScreen({super.key});
@@ -169,8 +170,15 @@ class _ResourcesScreen extends State<ResourcesScreen> {
     return AbsorbPointer(
       absorbing: downloading,
       child: ElevatedButton(
-        onPressed: () {
-          state.loadResources(downloadMissing: true);
+        onPressed: () async {
+          await state.loadResources(downloadMissing: true);
+          if (state.error != null) {
+            if (!mounted) return;
+            await showErrorDialog(context, <String>[state.error.toString()]);
+            // Reset both the error and stacktrace for further operation
+            state.error = null;
+            state.stackTrace = null;
+          }
         },
         style: ElevatedButton.styleFrom(
             backgroundColor: downloading ? Colors.grey : Colors.blue),