feat: Prevent exiting installer on new back button as well and show why exiting is not possible during patching

assets/i18n/en.json

@@ -95,7 +95,8 @@
         "installErrorDialogTitle": "Error",
         "installErrorDialogText1": "Root install is not possible with the current patches selection.\nRepatch your app or choose non-root install.",
         "installErrorDialogText2": "Non-root install is not possible with the current patches selection.\nRepatch your app or choose root install if you have your device rooted.",
-        "installErrorDialogText3": "Root install is not possible as the original APK was selected from storage.\nSelect an installed app or choose non-root install."
+        "installErrorDialogText3": "Root install is not possible as the original APK was selected from storage.\nSelect an installed app or choose non-root install.",
+        "noExit": "Installer is still running..."
     },
     "settingsView": {
         "widgetTitle": "Settings",

lib/ui/views/installer/installer_view.dart

@@ -29,6 +29,7 @@ class InstallerView extends StatelessWidget {
                     color: Theme.of(context).textTheme.headline6!.color,
                   ),
                 ),
+                onBackButtonPressed: () => model.onWillPop(context),
                 actions: <Widget>[
                   Visibility(
                     visible: !model.isPatching && !model.hasErrors,
@@ -143,13 +144,7 @@ class InstallerView extends StatelessWidget {
             ],
           ),
         ),
-        onWillPop: () async {
+        onWillPop: () => model.onWillPop(context),
-          if (!model.isPatching) {
-            model.cleanPatcher();
-            Navigator.of(context).pop();
-          }
-          return false;
-        },
       ),
     );
   }

lib/ui/views/installer/installer_viewmodel.dart

@@ -3,6 +3,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_background/flutter_background.dart';
 import 'package:flutter_i18n/flutter_i18n.dart';
+import 'package:fluttertoast/fluttertoast.dart';
 import 'package:permission_handler/permission_handler.dart';
 import 'package:revanced_manager/app/app.locator.dart';
 import 'package:revanced_manager/models/patch.dart';
@@ -215,4 +216,21 @@ class InstallerViewModel extends BaseViewModel {
         break;
     }
   }
+
+  Future<bool> onWillPop(BuildContext context) async {
+    if (isPatching) {
+      Fluttertoast.showToast(
+        msg: FlutterI18n.translate(
+          context,
+          'installerView.noExit',
+        ),
+        toastLength: Toast.LENGTH_LONG,
+        gravity: ToastGravity.CENTER,
+      );
+      return false;
+    }
+    cleanPatcher();
+    Navigator.of(context).pop();
+    return true;
+  }
 }

lib/ui/widgets/shared/custom_sliver_app_bar.dart

@@ -5,6 +5,7 @@ class CustomSliverAppBar extends StatelessWidget {
   final List<Widget>? actions;
   final PreferredSizeWidget? bottom;
   final bool isMainView;
+  final Function()? onBackButtonPressed;
 
   const CustomSliverAppBar({
     Key? key,
@@ -12,6 +13,7 @@ class CustomSliverAppBar extends StatelessWidget {
     this.actions,
     this.bottom,
     this.isMainView = false,
+    this.onBackButtonPressed,
   }) : super(key: key);
 
   @override
@@ -24,7 +26,7 @@ class CustomSliverAppBar extends StatelessWidget {
       automaticallyImplyLeading: !isMainView,
       flexibleSpace: FlexibleSpaceBar(
         titlePadding: EdgeInsets.only(
-          bottom: 14.0,
+          bottom: bottom != null ? 16.0 : 14.0,
           left: isMainView ? 20.0 : 55.0,
         ),
         title: title,
@@ -36,7 +38,8 @@ class CustomSliverAppBar extends StatelessWidget {
                 Icons.arrow_back,
                 color: Theme.of(context).textTheme.headline6!.color,
               ),
-              onPressed: () => Navigator.of(context).pop(),
+              onPressed:
+                  onBackButtonPressed ?? () => Navigator.of(context).pop(),
             ),
       backgroundColor: MaterialStateColor.resolveWith(
         (states) => states.contains(MaterialState.scrolledUnder)