Separate class and try catch

covas_mobile/lib/classes/alert.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+import '../main.dart';
+
+mixin ShowErrorDialog on State<LoginDemo> {
+  void showErrorDialog(BuildContext context, String text) {
+    // Create AlertDialog
+    AlertDialog dialog = AlertDialog(
+      title: Text("Error"),
+      content: Text(text),
+      actions: [
+        ElevatedButton(
+            child: Text("OK"),
+            style: ElevatedButton.styleFrom(
+                primary: Colors.red,
+                padding: EdgeInsets.symmetric(horizontal: 50, vertical: 20),
+                textStyle:
+                    TextStyle(fontSize: 15, fontWeight: FontWeight.normal)),
+            onPressed: () {
+              Navigator.of(context).pop("Yes, Of course!"); // Return value
+            }),
+      ],
+    );
+
+    // Call showDialog function to show dialog.
+    Future futureValue = showDialog(
+        context: context,
+        builder: (BuildContext context) {
+          return dialog;
+        });
+  }
+}

covas_mobile/lib/main.dart

@@ -4,6 +4,7 @@ import 'MyHomePage.dart';
 import 'package:http/http.dart' as http;
 import 'dart:convert';
 import 'dart:io';
+import 'classes/alert.dart';
 
 void main() {
   runApp(MyApp());
@@ -24,7 +25,7 @@ class LoginDemo extends StatefulWidget {
   _LoginDemoState createState() => _LoginDemoState();
 }
 
-class _LoginDemoState extends State<LoginDemo> {
+class _LoginDemoState extends State<LoginDemo> with ShowErrorDialog {
   TextEditingController inputPseudo = TextEditingController();
   TextEditingController inputPassword = TextEditingController();
   Future<void> _login(BuildContext context) async {
@@ -32,6 +33,7 @@ class _LoginDemoState extends State<LoginDemo> {
     var pseudo = inputPseudo.text;
     var password = inputPassword.text;
     if ((pseudo.isNotEmpty) && (password.isNotEmpty)) {
+      try {
         String credentials = "${pseudo}:${password}";
         Codec<String, String> stringToBase64 = utf8.fuse(base64);
         String encoded = stringToBase64.encode(credentials);
@@ -85,6 +87,9 @@ class _LoginDemoState extends State<LoginDemo> {
           }
           showErrorDialog(context, text);
         }
+      } catch (e) {
+        showErrorDialog(context, "${e}");
+      }
     } else {
       showErrorDialog(context, "Champ vide");
     }
@@ -169,31 +174,4 @@ class _LoginDemoState extends State<LoginDemo> {
       ),
     );
   }
-
-  showErrorDialog(BuildContext context, String text) {
-    // Create AlertDialog
-    AlertDialog dialog = AlertDialog(
-      title: Text("Error"),
-      content: Text(text),
-      actions: [
-        ElevatedButton(
-            child: Text("OK"),
-            style: ElevatedButton.styleFrom(
-                primary: Colors.red,
-                padding: EdgeInsets.symmetric(horizontal: 50, vertical: 20),
-                textStyle:
-                    TextStyle(fontSize: 15, fontWeight: FontWeight.normal)),
-            onPressed: () {
-              Navigator.of(context).pop("Yes, Of course!"); // Return value
-            }),
-      ],
-    );
-
-    // Call showDialog function to show dialog.
-    Future futureValue = showDialog(
-        context: context,
-        builder: (BuildContext context) {
-          return dialog;
-        });
-  }
 }