fix black screen

lib/src/visual/views/camera/camera_preview_components/camera_preview_controller_view.dart

@@ -168,6 +168,7 @@ class _CameraPreviewViewState extends State<CameraPreviewView> {
     super.initState();
     initVolumeControl();
     initAsync();
+    _checkAndInitCamera();
   }
 
   @override
@@ -176,12 +177,26 @@ class _CameraPreviewViewState extends State<CameraPreviewView> {
     if (oldWidget.isVisible != widget.isVisible) {
       if (widget.isVisible) {
         initVolumeControl();
+        _checkAndInitCamera();
       } else {
         _deInitVolumeControl();
       }
     }
   }
 
+  void _checkAndInitCamera() {
+    if (widget.isVisible &&
+        mc.cameraController == null &&
+        !mc.initCameraStarted) {
+      unawaited(
+        mc.selectCamera(
+          mc.selectedCameraDetails.cameraId,
+          false,
+        ),
+      );
+    }
+  }
+
   @override
   void dispose() {
     _videoRecordingTimer?.cancel();
@@ -686,7 +701,23 @@ class _CameraPreviewViewState extends State<CameraPreviewView> {
   Widget build(BuildContext context) {
     if (mc.selectedCameraDetails.cameraId >= AppEnvironment.cameras.length ||
         mc.cameraController == null) {
-      return Container();
+      if (widget.isVisible && !mc.initCameraStarted) {
+        WidgetsBinding.instance.addPostFrameCallback((_) {
+          _checkAndInitCamera();
+        });
+      }
+      // Show a loader instead of an empty container to prevent a black screen
+      // while the camera is initializing or if initialization failed.
+      return Center(
+        child: SizedBox(
+          height: 60,
+          width: 60,
+          child: ThreeRotatingDots(
+            size: 40,
+            color: context.color.primary,
+          ),
+        ),
+      );
     }
     return StreamBuilder(
       stream: userService.onUserUpdated,

lib/src/visual/views/camera/camera_preview_components/main_camera_controller.dart

@@ -155,6 +155,7 @@ class MainCameraController {
     } catch (e) {
       Log.error('Error querying available cameras: $e');
       initCameraStarted = false;
+      setState?.call();
       return;
     }
 
@@ -164,6 +165,7 @@ class MainCameraController {
         'Trying to select a non existing camera $cameraId >= ${AppEnvironment.cameras.length}',
       );
       initCameraStarted = false;
+      setState?.call();
       return;
     }
 
@@ -192,7 +194,7 @@ class MainCameraController {
       final hasMic = await micPermissionFuture;
       if (sessionId != _cameraSessionId) return;
 
-      final controller = CameraController(
+      var controller = CameraController(
         AppEnvironment.cameras[cameraId],
         ResolutionPreset.high,
         enableAudio: hasMic,
@@ -204,7 +206,21 @@ class MainCameraController {
       var assignedToGlobal = false;
       try {
         _initializeFuture = controller.initialize();
-        await _initializeFuture;
+        try {
+          await _initializeFuture;
+        } on CameraException catch (e) {
+          // If specific image format is unsupported on this hardware, fallback to default format
+          Log.warn('Initial camera format initialization failed ($e), trying fallback format...');
+          await controller.dispose();
+          controller = CameraController(
+            AppEnvironment.cameras[cameraId],
+            ResolutionPreset.high,
+            enableAudio: hasMic,
+          );
+          _initializeFuture = controller.initialize();
+          await _initializeFuture;
+        }
+
         if (sessionId != _cameraSessionId) {
           unawaited(controller.dispose());
           return;
@@ -256,6 +272,7 @@ class MainCameraController {
           unawaited(controller.dispose());
         }
         initCameraStarted = false;
+        setState?.call();
         return;
       }
     } else {

lib/src/visual/views/camera/camera_qr_scanner.view.dart

@@ -1,6 +1,8 @@
 import 'dart:async';
 import 'package:flutter/material.dart';
+import 'package:font_awesome_flutter/font_awesome_flutter.dart';
 import 'package:permission_handler/permission_handler.dart';
+import 'package:twonly/globals.dart';
 import 'package:twonly/src/database/daos/contacts.dao.dart';
 import 'package:twonly/src/database/twonly.db.dart';
 import 'package:twonly/src/services/key_verification.service.dart';
@@ -8,6 +10,7 @@ import 'package:twonly/src/utils/misc.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/camera_preview.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/camera_preview_controller_view.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/main_camera_controller.dart';
+import 'package:twonly/src/visual/views/camera/share_image_editor_components/action_button.dart';
 
 class QrCodeScannerView extends StatefulWidget {
   const QrCodeScannerView({
@@ -41,6 +44,7 @@ class QrCodeScannerViewState extends State<QrCodeScannerView> {
     }
     Permission.camera.isGranted.then((hasPermission) {
       if (hasPermission && mounted) {
+        AppState.hasCameraPermissions = true;
         unawaited(_mainCameraController.selectCamera(0, true));
       }
     });
@@ -100,6 +104,17 @@ class QrCodeScannerViewState extends State<QrCodeScannerView> {
                 ),
               ),
             ),
+          // Always-visible back button so the user can exit regardless of
+          // camera state (e.g. during init or after init failure).
+          Positioned(
+            left: 5,
+            top: MediaQuery.paddingOf(context).top + 10,
+            child: ActionButton(
+              FontAwesomeIcons.xmark,
+              tooltipText: context.lang.close,
+              onPressed: () => Navigator.pop(context),
+            ),
+          ),
         ],
       ),
     );

lib/src/visual/views/camera/camera_send_to.view.dart

@@ -1,10 +1,14 @@
 import 'dart:async';
 import 'package:flutter/material.dart';
+import 'package:font_awesome_flutter/font_awesome_flutter.dart';
 import 'package:permission_handler/permission_handler.dart';
+import 'package:twonly/globals.dart';
 import 'package:twonly/src/database/twonly.db.dart';
+import 'package:twonly/src/utils/misc.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/camera_preview.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/camera_preview_controller_view.dart';
 import 'package:twonly/src/visual/views/camera/camera_preview_components/main_camera_controller.dart';
+import 'package:twonly/src/visual/views/camera/share_image_editor_components/action_button.dart';
 
 class CameraSendToView extends StatefulWidget {
   const CameraSendToView(this.sendToGroup, {super.key});
@@ -24,6 +28,7 @@ class CameraSendToViewState extends State<CameraSendToView> {
     };
     Permission.camera.isGranted.then((hasPermission) {
       if (hasPermission && mounted) {
+        AppState.hasCameraPermissions = true;
         unawaited(_mainCameraController.selectCamera(0, true));
       }
     });
@@ -58,6 +63,17 @@ class CameraSendToViewState extends State<CameraSendToView> {
               isVisible: true,
             ),
           ),
+          // Always-visible back button so the user can exit regardless of
+          // camera state (e.g. during init or after init failure).
+          Positioned(
+            left: 5,
+            top: MediaQuery.paddingOf(context).top + 10,
+            child: ActionButton(
+              FontAwesomeIcons.xmark,
+              tooltipText: context.lang.close,
+              onPressed: () => Navigator.pop(context),
+            ),
+          ),
         ],
       ),
     );