Begin add settings

lib/widgets/pages/settings/messages_settings.dart

@@ -0,0 +1,66 @@
+import 'package:desktopapp/utils/mailer.dart';
+import 'package:flutter/material.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+class MessagesSettings extends StatefulWidget {
+  const MessagesSettings(
+      {Key? key, required this.settings, required this.prefs})
+      : super(key: key);
+
+  final MailerSettings settings;
+  final SharedPreferences prefs;
+
+  @override
+  _MessagesSettingsState createState() => _MessagesSettingsState();
+}
+
+class _MessagesSettingsState extends State<MessagesSettings> {
+  final TextEditingController controller = TextEditingController();
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      child: Column(
+        children: [
+          const Text('Messages :', style: TextStyle(fontSize: 24)),
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: Row(
+              children: [
+                Expanded(child: TextField(controller: controller)),
+                TextButton(
+                  child: const Text('Ajouter'),
+                  onPressed: () {
+                    setState(() {
+                      widget.settings.messages.add(controller.text);
+                      controller.clear();
+                      widget.settings.saveSettings(widget.prefs);
+                    });
+                  },
+                )
+              ],
+            ),
+          ),
+          Expanded(
+            child: ListView.builder(
+                itemCount: widget.settings.messages.length,
+                itemBuilder: (BuildContext context, int index) {
+                  return ListTile(
+                    title: Text(widget.settings.messages[index]),
+                    leading: IconButton(
+                      icon: const Icon(Icons.delete_rounded),
+                      onPressed: () {
+                        setState(() {
+                          widget.settings.messages.removeAt(index);
+                          widget.settings.saveSettings(widget.prefs);
+                        });
+                      },
+                    ),
+                  );
+                }),
+          )
+        ],
+      ),
+    );
+  }
+}