added error toast

android/app/src/main/AndroidManifest.xml

@@ -35,6 +35,14 @@
             android:value="2" />
     </application>
 
+    <queries>    
+        <intent>
+            <action android:name="android.intent.action.SEND" />
+            <data android:scheme="mailto" />
+            <category android:name="android.intent.category.DEFAULT" />
+        </intent>
+    </queries>
+
     <uses-permission android:name="android.permission.CAMERA" />
     <uses-feature android:name="android.hardware.camera" android:required="true" />
 

lib/l10n/intl_en.arb

@@ -70,6 +70,8 @@
     "sourceCode": "Source code",
     "reportIssue": "Report an issue",
     "writeEmail": "Write an email",
+    "youDontHaveMailApp": "You don't have any mail app installed.",
+    "copyEmail": "Copy email",
     "version": "Version",
     "versionNumber": "{version} ({buildNumber})",
     "@versionNumber": {

lib/l10n/intl_fr.arb

@@ -70,6 +70,8 @@
     "sourceCode": "Code source",
     "reportIssue": "Rapporter un problème",
     "writeEmail": "Écrire un email",
+    "youDontHaveMailApp": "Vous n'avez installé aucune application de messagerie.",
+    "copyEmail": "Copier un e-mail",
     "version": "Version",
     "versionNumber": "{version} ({buildNumber})",
     "@versionNumber": {

lib/l10n/intl_ru.arb

@@ -70,6 +70,8 @@
     "sourceCode": "Исходный код",
     "reportIssue": "Сообщить о проблеме",
     "writeEmail": "Написать на почту",
+    "youDontHaveMailApp": "У вас не установлено почтовое приложение.",
+    "copyEmail": "Скопировать адрес",
     "version": "Версия",
     "versionNumber": "{version} ({buildNumber})",
     "@versionNumber": {

lib/screens/settings/components/about/components/write_email/widget_list_tile_write_email.dart

@@ -1,6 +1,8 @@
+import 'package:clipboard/clipboard.dart';
 import 'package:flutter/material.dart';
 import 'package:lightmeter/environment.dart';
 import 'package:lightmeter/generated/l10n.dart';
+import 'package:lightmeter/res/dimens.dart';
 import 'package:provider/provider.dart';
 import 'package:url_launcher/url_launcher.dart';
 
@@ -13,11 +15,38 @@ class WriteEmailListTile extends StatelessWidget {
       leading: const Icon(Icons.email),
       title: Text(S.of(context).writeEmail),
       onTap: () {
-        launchUrl(
-          Uri.parse('mailto:${context.read<Environment>().contactEmail}?subject=M3 Lightmeter'),
-          mode: LaunchMode.externalApplication,
-        );
+        final email = context.read<Environment>().contactEmail;
+        final mailToUrl = Uri.parse('mailto:$email?subject=M3 Lightmeter');
+        canLaunchUrl(mailToUrl).then((canLaunch) {
+          if (canLaunch) {
+            launchUrl(
+              mailToUrl,
+              mode: LaunchMode.externalApplication,
+            );
+          } else {
+            ScaffoldMessenger.of(context).showSnackBar(
+              SnackBar(
+                content: Text(S.of(context).youDontHaveMailApp),
+                behavior: SnackBarBehavior.floating,
+                action: SnackBarAction(
+                  label: S.of(context).copyEmail,
+                  onPressed: () {
+                    FlutterClipboard.copy(email).then((_) {
+                      ScaffoldMessenger.of(context).clearSnackBars();
+                    });
+                  },
+                ),
+              ),
+            );
+          }
+        });
       },
     );
   }
+
+  void _copyEmail(BuildContext context) {
+    FlutterClipboard.copy(context.read<Environment>().contactEmail).then((_) {
+      ScaffoldMessenger.of(context).clearSnackBars();
+    });
+  }
 }

pubspec.yaml

@@ -9,6 +9,7 @@ environment:
 dependencies:
   app_settings: 4.2.0
   camera: 0.10.0+4
+  clipboard: 0.1.3
   exif: 3.1.2
   dynamic_color: 1.5.4
   firebase_core: 2.11.0