implemented release notes dialog

lib/l10n/intl_en.arb

@@ -119,5 +119,15 @@
     "tooltipUseLightSensor": "Use lightsensor",
     "tooltipUseCamera": "Use camera",
     "tooltipOpenSettings": "Open settings",
-    "exposurePair": "Exposure pair"
+    "exposurePair": "Exposure pair",
+    "whatsnew": "What's new?",
+    "changesInVersion": "Changes in version {version}:",
+    "@changesInVersion": {
+        "placeholders": {
+            "version": {
+                "type": "String"
+            }
+        }
+    },
+    "close": "Close"
 }

lib/screens/shared/release_notes_dialog/widget_dialog_release_notes.dart

@@ -0,0 +1,52 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart' show rootBundle;
+import 'package:lightmeter/generated/l10n.dart';
+import 'package:lightmeter/providers/user_preferences_provider.dart';
+import 'package:lightmeter/res/dimens.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+
+class ReleaseNotesDialog extends StatelessWidget {
+  const ReleaseNotesDialog({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: Text(S.of(context).whatsnew),
+      content: SingleChildScrollView(
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            FutureBuilder<PackageInfo>(
+              future: PackageInfo.fromPlatform(),
+              builder: (context, snapshot) => Text(
+                S.of(context).changesInVersion(snapshot.data?.version ?? ''),
+                style: Theme.of(context).textTheme.titleSmall,
+              ),
+            ),
+            const SizedBox(height: Dimens.grid8),
+            FutureBuilder<String>(
+              future: loadReleaseNotes(context),
+              builder: (context, snapshot) => Text(snapshot.data ?? ''),
+            ),
+          ],
+        ),
+      ),
+      actions: [
+        TextButton(
+          onPressed: Navigator.of(context).pop,
+          child: Text(S.of(context).close),
+        ),
+      ],
+    );
+  }
+
+  Future<String> loadReleaseNotes(BuildContext context) async {
+    String path(String locale) => 'assets/release_notes/release_notes_$locale.md';
+
+    try {
+      return rootBundle.loadString(path(UserPreferencesProvider.localeOf(context).name));
+    } catch (e) {
+      return rootBundle.loadString(path('en'));
+    }
+  }
+}

pubspec.yaml

@@ -65,6 +65,8 @@ flutter:
   uses-material-design: true
   assets:
     - assets/camera_stub_image.jpg
+    - assets/release_notes/release_notes_en.md
+    - assets/release_notes/release_notes_ru.md
 
 flutter_intl:
   enabled: true