refactor: PopScope Migration (#1674)

Co-authored-by: Benjamin Halko <benjaminhalko@hotmail.com>

lib/services/manager_api.dart

@@ -619,8 +619,8 @@ class ManagerAPI {
     return showDialog(
       barrierDismissible: false,
       context: context,
-      builder: (context) => WillPopScope(
-        onWillPop: () async => false,
+      builder: (context) => PopScope(
+        canPop: false,
         child: AlertDialog(
           title: Text(t.warning),
           content: ValueListenableBuilder(

lib/ui/views/installer/installer_view.dart

@@ -16,12 +16,15 @@ class InstallerView extends StatelessWidget {
     return ViewModelBuilder<InstallerViewModel>.reactive(
       onViewModelReady: (model) => model.initialize(context),
       viewModelBuilder: () => InstallerViewModel(),
-      builder: (context, model, child) => WillPopScope(
-        /* 
-          TODO(any): migrate to [PopScope],
-          we've tried to migrate it two times but 
-          reverted it because we couldn't exit out of the screen. 
-        */
+      builder: (context, model, child) => PopScope(
+        canPop: !model.isPatching,
+        onPopInvoked: (bool didPop) {
+          if (didPop) {
+            model.onPop();
+          } else {
+            model.onPopAttempt(context);
+          }
+        },
         child: SafeArea(
           top: false,
           bottom: model.isPatching,
@@ -83,7 +86,7 @@ class InstallerView extends StatelessWidget {
                     maxLines: 1,
                     overflow: TextOverflow.ellipsis,
                   ),
-                  onBackButtonPressed: () => model.onWillPop(context),
+                  onBackButtonPressed: () => Navigator.maybePop(context),
                   bottom: PreferredSize(
                     preferredSize: const Size(double.infinity, 1.0),
                     child: GradientProgressIndicator(progress: model.progress),
@@ -111,7 +114,6 @@ class InstallerView extends StatelessWidget {
             ),
           ),
         ),
-        onWillPop: () => model.onWillPop(context),
       ),
     );
   }

lib/ui/views/installer/installer_viewmodel.dart

@@ -526,25 +526,23 @@ class InstallerViewModel extends BaseViewModel {
     }
   }
 
-  Future<bool> onWillPop(BuildContext context) async {
-    if (isPatching) {
-      if (!cancel) {
-        cancel = true;
-        _toast.showBottom(t.installerView.pressBackAgain);
-      } else if (!isCanceled) {
-        await stopPatcher();
-      } else {
-        _toast.showBottom(t.installerView.noExit);
-      }
-      return false;
+  Future<void> onPopAttempt(BuildContext context) async {
+    if (!cancel) {
+      cancel = true;
+      _toast.showBottom(t.installerView.pressBackAgain);
+    } else if (!isCanceled) {
+      await stopPatcher();
+    } else {
+      _toast.showBottom(t.installerView.noExit);
     }
+  }
+
+  void onPop() {
     if (!cancel) {
       cleanPatcher();
     } else {
       _patcherAPI.cleanPatcher();
     }
-    screenshotCallback.dispose();
-    Navigator.of(context).pop();
-    return true;
+    ScreenshotCallback().dispose();
   }
 }

lib/ui/views/navigation/navigation_view.dart

@@ -13,13 +13,11 @@ class NavigationView extends StatelessWidget {
     return ViewModelBuilder<NavigationViewModel>.reactive(
       onViewModelReady: (model) => model.initialize(context),
       viewModelBuilder: () => locator<NavigationViewModel>(),
-      builder: (context, model, child) => WillPopScope(
-        onWillPop: () async {
-          if (model.currentIndex == 0) {
-            return true;
-          } else {
+      builder: (context, model, child) => PopScope(
+        canPop: model.currentIndex == 0,
+        onPopInvoked: (bool didPop) {
+          if (!didPop) {
             model.setIndex(0);
-            return false;
           }
         },
         child: Scaffold(