Fehlerkorrekturen

lib/content_views/main_page.dart

@@ -230,7 +230,7 @@ class _MainPageState extends State<MainPage> {
               getDefaultButton(
                   _loggedOut ? 'Anmelden' : 'Abmelden',
                   image: Image.asset(_loggedOut ? 'assets/anmelden.png' : 'assets/abmelden.png', width: 30, height: 30),
-                  () async => {_logout()}),
+                  () async => {_logout(context)}),
               Expanded(
                 child: Container(
                   decoration: BoxDecoration(
@@ -305,20 +305,58 @@ class _MainPageState extends State<MainPage> {
     }
   }
 
-  _logout() {
+  _logout(context) {
     if (!_loggedOut) {
-      _sendLogoutMessage();
-
-      Future.delayed(const Duration(seconds: 1), () async {
-        MqttCore.instance.diconnect();
-      });
+      showLogoutAlertDialog(context);
     } else {
       MqttCore.setup();
+
+      _loggedOut = false;
+
+      setState(() {});
     }
+  }
 
-    _loggedOut = !_loggedOut;
+  showLogoutAlertDialog(BuildContext context) {
+    Widget yesButton = TextButton(
+      child: const Text("Ja"),
+      onPressed: () {
+        Navigator.of(context).pop();
+        _sendLogoutMessage();
 
-    setState(() {});
+        Future.delayed(const Duration(seconds: 1), () async {
+          MqttCore.instance.diconnect();
+        });
+
+        _loggedOut = true;
+
+        setState(() {});
+      },
+    );
+
+    Widget noButton = TextButton(
+      child: const Text("Nein"),
+      onPressed: () {
+        Navigator.of(context).pop();
+      },
+    );
+
+    // set up the AlertDialog
+    AlertDialog alert = AlertDialog(
+      title: const Text("Warnung"),
+      content: const Text("Wollen Sie sich wirklich abmelden?"),
+      actions: [
+        yesButton, noButton,
+      ],
+    );
+
+    // show the dialog
+    showDialog(
+      context: context,
+      builder: (BuildContext context) {
+        return alert;
+      },
+    );
   }
 
   _sendLogoutMessage() {