feat(ui_auth): add a way to customize PlatformException text (#171)

Author: lesnitsky

packages/firebase_ui_auth/lib/src/widgets/error_text.dart

@@ -6,6 +6,7 @@ import 'package:firebase_auth/firebase_auth.dart' show FirebaseAuthException;
 import 'package:firebase_ui_localizations/firebase_ui_localizations.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart' show PlatformException;
 
 import '../flows/phone_auth_flow.dart';
 
@@ -38,7 +39,7 @@ String? localizedErrorText(
 /// A widget which displays error text for a given Firebase error code.
 /// {@endtemplate}
 class ErrorText extends StatelessWidget {
-  /// A way to customize localized error messages.
+  /// A way to customize localized error messages for [FirebaseAuthException].
   ///
   /// Example usage:
   /// ```dart
@@ -54,6 +55,19 @@ class ErrorText extends StatelessWidget {
     FirebaseAuthException exception,
   )? localizeError;
 
+  /// A way to customize error message for [PlatformException]
+  ///
+  /// Example usage:
+  /// ```dart
+  /// ErrorText.localizePlatformError = (BuildContext context, PlatformException e) {
+  ///   if (e.code == "network_error") return "Please check your internet connection.";
+  ///   return "Oh no! Something went wrong.";
+  /// }
+  static String Function(
+    BuildContext context,
+    PlatformException exception,
+  )? localizePlatformError;
+
   /// A way to customize the widget that is used across the library to show
   /// error hints. By default a localized text is used with a color set to
   /// [ColorScheme.error] under [MaterialApp] and
@@ -106,6 +120,10 @@ class ErrorText extends StatelessWidget {
       }
     }
 
+    if (exception is PlatformException && localizePlatformError != null) {
+      text = localizePlatformError!(context, exception as PlatformException);
+    }
+
     return Text(
       text,
       textAlign: textAlign,