修复：拍照死机问题

优化：积分不够的时候跳转到充值页面
优化：生成图片页面
2026-03-29 23:53:24 +08:00 · 2026-03-29 21:06:27 +08:00 · 2026-03-29 20:41:45 +08:00
15 changed files with 1039 additions and 409 deletions
--- a/android/app/src/main/AndroidManifest.xml
+++ b/android/app/src/main/AndroidManifest.xml
@ -1,8 +1,14 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="32" />
-    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="32" />
+    <!-- 与 camera_android_camerax 中 maxSdkVersion=28 合并冲突：沿用本应用上限 API 32 -->
+    <uses-permission
+        android:name="android.permission.WRITE_EXTERNAL_STORAGE"
+        android:maxSdkVersion="32"
+        tools:replace="android:maxSdkVersion" />
    <uses-permission android:name="com.android.vending.BILLING" />
    <application
        android:usesCleartextTraffic="${usesCleartextTraffic}"
--- a/ios/Runner/GeneratedPluginRegistrant.m
+++ b/ios/Runner/GeneratedPluginRegistrant.m
@ -12,6 +12,12 @@
@import adjust_sdk;
 #endif

+#if __has_include(<camera_avfoundation/CameraPlugin.h>)
+#import <camera_avfoundation/CameraPlugin.h>
+#else
+@import camera_avfoundation;
+#endif
+
 #if __has_include(<device_info_plus/FPPDeviceInfoPlusPlugin.h>)
 #import <device_info_plus/FPPDeviceInfoPlusPlugin.h>
 #else
@ -48,6 +54,12 @@
@import in_app_purchase_storekit;
 #endif

+#if __has_include(<permission_handler_apple/PermissionHandlerPlugin.h>)
+#import <permission_handler_apple/PermissionHandlerPlugin.h>
+#else
+@import permission_handler_apple;
+#endif
+
 #if __has_include(<photo_manager/PhotoManagerPlugin.h>)
 #import <photo_manager/PhotoManagerPlugin.h>
 #else
@ -100,12 +112,14 @@

 + (void)registerWithRegistry:(NSObject<FlutterPluginRegistry>*)registry {
  [AdjustSdk registerWithRegistrar:[registry registrarForPlugin:@"AdjustSdk"]];
+  [CameraPlugin registerWithRegistrar:[registry registrarForPlugin:@"CameraPlugin"]];
  [FPPDeviceInfoPlusPlugin registerWithRegistrar:[registry registrarForPlugin:@"FPPDeviceInfoPlusPlugin"]];
  [FacebookAppEventsPlugin registerWithRegistrar:[registry registrarForPlugin:@"FacebookAppEventsPlugin"]];
  [FlutterNativeSplashPlugin registerWithRegistrar:[registry registrarForPlugin:@"FlutterNativeSplashPlugin"]];
  [GalPlugin registerWithRegistrar:[registry registrarForPlugin:@"GalPlugin"]];
  [FLTImagePickerPlugin registerWithRegistrar:[registry registrarForPlugin:@"FLTImagePickerPlugin"]];
  [InAppPurchasePlugin registerWithRegistrar:[registry registrarForPlugin:@"InAppPurchasePlugin"]];
+  [PermissionHandlerPlugin registerWithRegistrar:[registry registrarForPlugin:@"PermissionHandlerPlugin"]];
  [PhotoManagerPlugin registerWithRegistrar:[registry registrarForPlugin:@"PhotoManagerPlugin"]];
  [ScreenSecurePlugin registerWithRegistrar:[registry registrarForPlugin:@"ScreenSecurePlugin"]];
  [SharedPreferencesPlugin registerWithRegistrar:[registry registrarForPlugin:@"SharedPreferencesPlugin"]];
--- a/lib/core/auth/auth_service.dart
+++ b/lib/core/auth/auth_service.dart
@ -127,6 +127,27 @@ class AuthService {
    }
  }

+  /// 系统相册/相机 Activity 返回后，若开启了截屏防护（[UserState.safeArea]），部分机型会黑屏卡死甚至重启。
+  /// 在整段选图流程外包一层：临时关闭防护，结束后按当前配置恢复。
+  static Future<T> runWithNativeMediaPicker<T>(Future<T> Function() action) async {
+    if (defaultTargetPlatform != TargetPlatform.android &&
+        defaultTargetPlatform != TargetPlatform.iOS) {
+      return await action();
+    }
+    try {
+      await ScreenSecure.disableScreenshotBlock();
+      await ScreenSecure.disableScreenRecordBlock();
+      _logMsg('native media picker: ScreenSecure released');
+    } on ScreenSecureException catch (e) {
+      _logMsg('native media picker: disable failed: ${e.message}');
+    }
+    try {
+      return await action();
+    } finally {
+      await _applyScreenSecure(UserState.safeArea.value);
+    }
+  }
+
  /// 将 common_info 响应保存到全局，并解析 surge 中的 lucky（是否开启三方支付）
  static void _saveCommonInfoToState(Map<String, dynamic> data) {
    final reveal = data['reveal'] as int?;
--- a/lib/core/theme/app_colors.dart
+++ b/lib/core/theme/app_colors.dart
@ -6,6 +6,10 @@ abstract final class AppColors {
  static const Color primary = Color(0xFF8B5CF6);
  static const Color primaryLight = Color(0x338B5CF6); // #8B5CF620
  static const Color primaryShadow = Color(0x338B5CF6); // #8B5CF620 for shadow
+  /// 底栏选中、分辨率 chip 等：透出底层，字仍用 [surface] 可读
+  static Color get primaryGlass => primary.withValues(alpha: 0.58);
+  /// 生成页主按钮：略不透明，保证主操作仍醒目
+  static Color get primaryGlassEmphasis => primary.withValues(alpha: 0.72);

  // Neutrals
  static const Color background = Color(0xFFFAFAFA);
--- a/lib/core/util/image_compress.dart
+++ b/lib/core/util/image_compress.dart
@ -0,0 +1,37 @@
+import 'dart:io';
+
+import 'package:image/image.dart' as img;
+import 'package:path_provider/path_provider.dart';
+
+/// 上传前压缩：限制长边、JPEG 质量，减轻内存与带宽；解码失败时返回原文件。
+Future<File> compressImageForUpload(
+  File source, {
+  int maxSide = 2048,
+  int jpegQuality = 85,
+}) async {
+  try {
+    final raw = await source.readAsBytes();
+    final image = img.decodeImage(raw);
+    if (image == null) return source;
+
+    var work = image;
+    if (work.width > maxSide || work.height > maxSide) {
+      if (work.width >= work.height) {
+        work = img.copyResize(work, width: maxSide, interpolation: img.Interpolation.linear);
+      } else {
+        work = img.copyResize(work, height: maxSide, interpolation: img.Interpolation.linear);
+      }
+    }
+
+    final jpg = img.encodeJpg(work, quality: jpegQuality);
+
+    final dir = await getTemporaryDirectory();
+    final out = File(
+      '${dir.path}/upload_${DateTime.now().millisecondsSinceEpoch}.jpg',
+    );
+    await out.writeAsBytes(jpg, flush: true);
+    return out;
+  } catch (_) {
+    return source;
+  }
+}
--- a/lib/features/gallery/gallery_screen.dart
+++ b/lib/features/gallery/gallery_screen.dart
@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:typed_data';

 import 'package:flutter/material.dart';
@ -35,12 +36,14 @@ class _GalleryScreenState extends State<GalleryScreen> {
  final ScrollController _scrollController = ScrollController();
  static const int _pageSize = 20;

-  /// 与首页一致：足够可见比例的格子才自动静音循环播视频（允许多个）
-  static const double _videoVisibilityThreshold = 0.15;
+  /// 略低于首页：网格边缘格子可见但比例偏低时也应计入「在屏」
+  static const double _videoVisibilityThreshold = 0.08;
+  /// 一屏约 2×(3～4) 个格子；不再强行只播 2 路（会总挑中间行）。滑出后 [VideoCard] 会释放解码器，此处仅防极端滚动时实例过多
+  static const int _maxConcurrentGalleryVideos = 16;
  Set<int> _visibleVideoIndices = {};
  final Set<int> _userPausedVideoIndices = {};
  final Map<int, double> _cardVisibleFraction = {};
-  bool _visibilityReconcileScheduled = false;
+  Timer? _visibilityDebounce;

  /// [IndexedStack] 非当前 Tab 时子树可见性常为 0；首次切到本页时若仅打一次 [notifyNow]，
  /// 可能在 Grid 尚未挂载（仍在 loading）或首帧未稳定时执行，导致预览不自动播放。
@ -85,6 +88,7 @@ class _GalleryScreenState extends State<GalleryScreen> {

  @override
  void dispose() {
+    _visibilityDebounce?.cancel();
    _scrollController.dispose();
    super.dispose();
  }
@ -105,26 +109,30 @@ class _GalleryScreenState extends State<GalleryScreen> {
    } else {
      _cardVisibleFraction.remove(index);
    }
-    if (_visibilityReconcileScheduled) return;
-    _visibilityReconcileScheduled = true;
-    WidgetsBinding.instance.addPostFrameCallback((_) {
-      _visibilityReconcileScheduled = false;
+    // 防抖：滚动时可见性回调极频繁，立刻 setState 会让 VideoCard / FutureBuilder 反复重建导致闪屏
+    _visibilityDebounce?.cancel();
+    _visibilityDebounce = Timer(const Duration(milliseconds: 120), () {
      if (mounted) _reconcileVisibleVideoIndicesFromDetector();
    });
  }

  void _reconcileVisibleVideoIndicesFromDetector() {
    final items = _gridItems;
-    final next = <int>{};
+    final scored = <MapEntry<int, double>>[];
    for (final e in _cardVisibleFraction.entries) {
      final i = e.key;
      if (i < 0 || i >= items.length) continue;
      if (e.value < _videoVisibilityThreshold) continue;
      final url = items[i].videoUrl;
      if (url != null && url.isNotEmpty) {
-        next.add(i);
+        scored.add(MapEntry(i, e.value));
      }
    }
+    scored.sort((a, b) => b.value.compareTo(a.value));
+    final next = scored
+        .take(_maxConcurrentGalleryVideos)
+        .map((e) => e.key)
+        .toSet();
    _userPausedVideoIndices.removeWhere((i) => !next.contains(i));
    if (!_setsEqual(next, _visibleVideoIndices)) {
      setState(() => _visibleVideoIndices = next);
@ -273,6 +281,7 @@ class _GalleryScreenState extends State<GalleryScreen> {
                                  physics:
                                      const AlwaysScrollableScrollPhysics(),
                                  controller: _scrollController,
+                                  cacheExtent: 800,
                                  padding: EdgeInsets.fromLTRB(
                                    AppSpacing.screenPadding,
                                    AppSpacing.xl,
@ -324,33 +333,35 @@ class _GalleryScreenState extends State<GalleryScreen> {
                                              _onGridCardVisibilityChanged(
                                                  index, info)
                                          : (_) {},
-                                      child: VideoCard(
-                                        key: ValueKey(detectorKey),
-                                        imageUrl: media.imageUrl ??
-                                            videoUrl ??
-                                            '',
-                                        cover: hasVideo
-                                            ? _VideoThumbnailCover(
-                                                videoUrl: media.videoUrl!,
-                                              )
-                                            : null,
-                                        videoUrl: hasVideo ? videoUrl : null,
-                                        credits: '50',
-                                        showCreditsBadge: false,
-                                        showBottomGenerateButton: false,
-                                        isActive: widget.isActive &&
-                                            hasVideo &&
-                                            _visibleVideoIndices
-                                                .contains(index) &&
-                                            !_userPausedVideoIndices
-                                                .contains(index),
-                                        onPlayRequested: () => setState(() =>
-                                            _userPausedVideoIndices
-                                                .remove(index)),
-                                        onStopRequested: () => setState(() =>
-                                            _userPausedVideoIndices
-                                                .add(index)),
-                                        onGenerateSimilar: openResult,
+                                      child: RepaintBoundary(
+                                        child: VideoCard(
+                                          key: ValueKey(detectorKey),
+                                          imageUrl: media.imageUrl ??
+                                              videoUrl ??
+                                              '',
+                                          cover: hasVideo
+                                              ? _VideoThumbnailCover(
+                                                  videoUrl: media.videoUrl!,
+                                                )
+                                              : null,
+                                          videoUrl: hasVideo ? videoUrl : null,
+                                          credits: '50',
+                                          showCreditsBadge: false,
+                                          showBottomGenerateButton: false,
+                                          isActive: widget.isActive &&
+                                              hasVideo &&
+                                              _visibleVideoIndices
+                                                  .contains(index) &&
+                                              !_userPausedVideoIndices
+                                                  .contains(index),
+                                          onPlayRequested: () => setState(() =>
+                                              _userPausedVideoIndices
+                                                  .remove(index)),
+                                          onStopRequested: () => setState(() =>
+                                              _userPausedVideoIndices
+                                                  .add(index)),
+                                          onGenerateSimilar: openResult,
+                                        ),
                                      ),
                                    );
                                  },
@ -364,20 +375,45 @@ class _GalleryScreenState extends State<GalleryScreen> {
  }
 }

-class _VideoThumbnailCover extends StatelessWidget {
+class _VideoThumbnailCover extends StatefulWidget {
  const _VideoThumbnailCover({required this.videoUrl});

  final String videoUrl;

+  @override
+  State<_VideoThumbnailCover> createState() => _VideoThumbnailCoverState();
+}
+
+class _VideoThumbnailCoverState extends State<_VideoThumbnailCover> {
+  /// 必须在 State 内固定同一 Future；否则父级每次 build 新建 Future，[FutureBuilder] 会重置并闪一下占位图
+  late Future<Uint8List?> _thumbFuture;
+
+  @override
+  void initState() {
+    super.initState();
+    _thumbFuture =
+        VideoThumbnailCache.instance.getThumbnail(widget.videoUrl);
+  }
+
+  @override
+  void didUpdateWidget(covariant _VideoThumbnailCover oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (oldWidget.videoUrl != widget.videoUrl) {
+      _thumbFuture =
+          VideoThumbnailCache.instance.getThumbnail(widget.videoUrl);
+    }
+  }
+
  @override
  Widget build(BuildContext context) {
    return FutureBuilder<Uint8List?>(
-      future: VideoThumbnailCache.instance.getThumbnail(videoUrl),
+      future: _thumbFuture,
      builder: (context, snapshot) {
        if (snapshot.hasData && snapshot.data != null) {
          return Image.memory(
            snapshot.data!,
            fit: BoxFit.cover,
+            gaplessPlayback: true,
          );
        }
        return Container(
--- a/lib/features/gallery/video_thumbnail_cache.dart
+++ b/lib/features/gallery/video_thumbnail_cache.dart
@ -15,6 +15,37 @@ class VideoThumbnailCache {
  static const int _maxWidth = 400;
  static const int _quality = 75;

+  /// 全屏背景等大图：无 ExoPlayer，仅抽一帧 JPEG（例如生成页背景，长边约 [maxWidth]）
+  Future<Uint8List?> getPosterFrame(String videoUrl, {int maxWidth = 1024}) async {
+    final key = '${_cacheKey(videoUrl)}_poster_$maxWidth';
+    final cacheDir = await _getCacheDir();
+    final file = File('${cacheDir.path}/$key.jpg');
+
+    if (await file.exists()) {
+      return file.readAsBytes();
+    }
+
+    try {
+      final path = await VideoThumbnail.thumbnailFile(
+        video: videoUrl,
+        thumbnailPath: cacheDir.path,
+        imageFormat: ImageFormat.JPEG,
+        maxWidth: maxWidth,
+        quality: 78,
+      );
+      if (path != null) {
+        final cached = File(path);
+        final bytes = await cached.readAsBytes();
+        if (cached.path != file.path) {
+          await file.writeAsBytes(bytes);
+          cached.deleteSync();
+        }
+        return bytes;
+      }
+    } catch (_) {}
+    return null;
+  }
+
  Future<Uint8List?> getThumbnail(String videoUrl) async {
    final key = _cacheKey(videoUrl);
    final cacheDir = await _getCacheDir();
--- a/lib/features/generate_video/generate_video_screen.dart
+++ b/lib/features/generate_video/generate_video_screen.dart
@ -1,4 +1,5 @@
 import 'dart:io';
+import 'dart:typed_data';

 import 'package:cached_network_image/cached_network_image.dart';
 import 'package:flutter/material.dart';
@ -8,17 +9,20 @@ import 'package:http/http.dart' as http;
 import 'package:video_player/video_player.dart';

 import '../../core/auth/auth_service.dart';
+import '../../core/util/image_compress.dart';
 import '../../core/log/app_logger.dart';
 import '../../core/theme/app_colors.dart';
 import '../../core/theme/app_spacing.dart';
 import '../../core/theme/app_typography.dart';
 import '../../core/user/account_refresh.dart';
 import '../../core/user/user_state.dart';
+import '../../features/gallery/video_thumbnail_cache.dart';
 import '../../features/home/home_playback_resume.dart';
 import '../../features/home/models/task_item.dart';
 import '../../shared/widgets/top_nav_bar.dart';

 import '../../core/api/services/image_api.dart';
+import 'in_app_camera_page.dart';
 import 'widgets/album_picker_sheet.dart';

 /// Generate Video screen - matches Pencil mmLB5
@ -38,6 +42,10 @@ enum _Resolution { p480, p720 }
 class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
  _Resolution _selectedResolution = _Resolution.p480;
  bool _isGenerating = false;
+  /// 防止在选图/相机流程未结束时再次进入，避免并发 native picker / ScreenSecure 错乱
+  bool _isPickingMedia = false;
+  /// 应用内相机打开时暂停背景 [VideoPlayer]，避免与 CameraPreview 争用 Surface
+  bool _suspendBackgroundVideo = false;

  int get _currentCredits {
    final task = widget.task;
@ -77,7 +85,7 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
  /// Click flow per docs/generate_video.md: tap Generate Video -> image picker
  /// (camera or gallery) -> after image selected -> proceed to API.
  Future<void> _onGenerateButtonTap() async {
-    if (_isGenerating) return;
+    if (_isGenerating || _isPickingMedia) return;

    final userCredits = UserState.credits.value ?? 0;
    if (userCredits < _currentCredits) {
@ -87,19 +95,62 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
      return;
    }

-    final path = await showModalBottomSheet<String>(
-      context: context,
-      isScrollControlled: true,
-      backgroundColor: Colors.transparent,
-      builder: (ctx) => SizedBox(
-        height: MediaQuery.sizeOf(ctx).height * 0.92,
-        child: const AlbumPickerSheet(),
-      ),
-    );
-    if (path == null || path.isEmpty || !mounted) return;
+    _isPickingMedia = true;
+    if (mounted) setState(() {});

-    final file = File(path);
-    await _runGenerationApi(file);
+    try {
+      await AuthService.runWithNativeMediaPicker(() async {
+        final path = await showModalBottomSheet<String>(
+          context: context,
+          isScrollControlled: true,
+          backgroundColor: Colors.transparent,
+          builder: (ctx) => SizedBox(
+            height: MediaQuery.sizeOf(ctx).height * 0.92,
+            child: const AlbumPickerSheet(),
+          ),
+        );
+        if (!mounted) return;
+
+        if (path == kAlbumPickerRequestCamera) {
+          // 应用内相机：推全屏页前暂停背景视频，返回后短暂延迟再恢复，降低 GPU 切换毛刺
+          setState(() => _suspendBackgroundVideo = true);
+          await Future<void>.delayed(const Duration(milliseconds: 80));
+          if (!mounted) return;
+          final capturedPath = await Navigator.of(context, rootNavigator: true)
+              .push<String>(
+            MaterialPageRoute<String>(
+              fullscreenDialog: true,
+              builder: (context) => const InAppCameraPage(),
+            ),
+          );
+          if (mounted) {
+            await Future<void>.delayed(const Duration(milliseconds: 150));
+            if (mounted) {
+              setState(() => _suspendBackgroundVideo = false);
+              WidgetsBinding.instance.addPostFrameCallback((_) {
+                if (mounted) setState(() {});
+              });
+            }
+          }
+          if (!mounted) return;
+          if (capturedPath != null && capturedPath.isNotEmpty) {
+            final f = File(capturedPath);
+            if (await f.exists()) {
+              await _runGenerationApi(f);
+            }
+          }
+          return;
+        }
+
+        if (path == null || path.isEmpty) return;
+
+        final file = File(path);
+        await _runGenerationApi(file);
+      });
+    } finally {
+      _isPickingMedia = false;
+      if (mounted) setState(() {});
+    }
  }

  Future<void> _runGenerationApi(File file) async {
@ -108,8 +159,14 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
    try {
      await AuthService.loginComplete;

-      final size = await file.length();
-      final ext = file.path.split('.').last.toLowerCase();
+      final toUpload = await compressImageForUpload(
+        file,
+        maxSide: 1024,
+        jpegQuality: 75,
+      );
+
+      final size = await toUpload.length();
+      final ext = toUpload.path.split('.').last.toLowerCase();
      final contentType = ext == 'png'
          ? 'image/png'
          : ext == 'gif'
@ -152,7 +209,7 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
        headers['Content-Type'] = contentType;
      }

-      final bytes = await file.readAsBytes();
+      final bytes = await toUpload.readAsBytes();
      final uploadResponse = await http.put(
        Uri.parse(uploadUrl),
        headers: headers,
@ -215,44 +272,67 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {

  @override
  Widget build(BuildContext context) {
+    final topInset = MediaQuery.paddingOf(context).top;
+    final creditsDisplay =
+        UserCreditsData.of(context)?.creditsDisplay ?? '--';
+
    return Scaffold(
-      backgroundColor: AppColors.background,
+      extendBodyBehindAppBar: true,
+      backgroundColor: Colors.black,
      appBar: PreferredSize(
-        preferredSize: const Size.fromHeight(56),
-        child: TopNavBar(
-          title: 'Generate',
-          showBackButton: true,
-          onBack: () => Navigator.of(context).pop(),
+        preferredSize: Size.fromHeight(topInset + 56),
+        child: Container(
+          padding: EdgeInsets.only(top: topInset),
+          decoration: BoxDecoration(
+            gradient: LinearGradient(
+              begin: Alignment.topCenter,
+              end: Alignment.bottomCenter,
+              colors: [
+                Colors.black.withValues(alpha: 0.72),
+                Colors.black.withValues(alpha: 0.35),
+                Colors.black.withValues(alpha: 0.0),
+              ],
+              stops: const [0.0, 0.55, 1.0],
+            ),
+          ),
+          child: SizedBox(
+            height: 56,
+            child: TopNavBar(
+              title: 'Generate',
+              credits: creditsDisplay,
+              onCreditsTap: () => Navigator.of(context).pushNamed('/recharge'),
+              showBackButton: true,
+              onBack: () => Navigator.of(context).pop(),
+              backgroundColor: Colors.transparent,
+              foregroundColor: AppColors.surface,
+            ),
+          ),
        ),
      ),
-      body: Column(
+      body: Stack(
+        fit: StackFit.expand,
        children: [
-          Expanded(
-            child: SingleChildScrollView(
-              padding: const EdgeInsets.fromLTRB(
-                AppSpacing.screenPaddingLarge,
-                AppSpacing.screenPaddingLarge,
-                AppSpacing.screenPaddingLarge,
-                AppSpacing.lg,
-              ),
-              child: Column(
-                crossAxisAlignment: CrossAxisAlignment.stretch,
-                children: [
-                  _CreditsCard(
-                    credits:
-                        UserCreditsData.of(context)?.creditsDisplay ?? '--',
-                  ),
-                  const SizedBox(height: AppSpacing.xxl),
-                  _VideoPreviewArea(
-                    videoUrl: widget.task?.previewVideoUrl,
-                    imageUrl: widget.task?.previewImageUrl,
-                  ),
-                ],
+          _GenerateBackgroundLayer(
+            videoUrl: widget.task?.previewVideoUrl,
+            imageUrl: widget.task?.previewImageUrl,
+            suspendVideoPlayback: _suspendBackgroundVideo,
+          ),
+          Positioned.fill(
+            child: DecoratedBox(
+              decoration: BoxDecoration(
+                gradient: LinearGradient(
+                  begin: Alignment.topCenter,
+                  end: Alignment.bottomCenter,
+                  colors: [
+                    Colors.black.withValues(alpha: 0.12),
+                    Colors.black.withValues(alpha: 0.55),
+                  ],
+                  stops: const [0.45, 1.0],
+                ),
              ),
            ),
          ),
          SafeArea(
-            top: false,
            child: Padding(
              padding: const EdgeInsets.fromLTRB(
                AppSpacing.screenPaddingLarge,
@ -261,18 +341,21 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
                AppSpacing.screenPaddingLarge,
              ),
              child: Column(
-                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
+                  const Spacer(),
                  if (_hasVideo)
-                    _ResolutionToggle(
-                      selected: _selectedResolution,
-                      onChanged: (r) => setState(() => _selectedResolution = r),
+                    Center(
+                      child: _ResolutionToggle(
+                        selected: _selectedResolution,
+                        onChanged: (r) =>
+                            setState(() => _selectedResolution = r),
+                      ),
                    ),
                  if (_hasVideo) const SizedBox(height: AppSpacing.xxl),
                  _GenerateButton(
                    onGenerate: _onGenerateButtonTap,
-                    isLoading: _isGenerating,
+                    isLoading: _isGenerating || _isPickingMedia,
                    credits: _currentCredits.toString(),
                  ),
                ],
@ -285,338 +368,282 @@ class _GenerateVideoScreenState extends State<GenerateVideoScreen> {
  }
 }

-class _CreditsCard extends StatelessWidget {
-  const _CreditsCard({required this.credits});
-
-  final String credits;
-
-  @override
-  Widget build(BuildContext context) {
-    return Container(
-      padding: const EdgeInsets.symmetric(
-        horizontal: AppSpacing.xxl,
-        vertical: AppSpacing.xl,
-      ),
-      decoration: BoxDecoration(
-        color: AppColors.primary,
-        borderRadius: BorderRadius.circular(16),
-        border: Border.all(
-          color: AppColors.primary.withValues(alpha: 0.5),
-        ),
-        boxShadow: [
-          BoxShadow(
-            color: AppColors.primaryShadow.withValues(alpha: 0.25),
-            blurRadius: 8,
-            offset: const Offset(0, 2),
-          ),
-        ],
-      ),
-      child: Row(
-        children: [
-          const Icon(LucideIcons.sparkles, size: 28, color: AppColors.surface),
-          const SizedBox(width: AppSpacing.md),
-          Column(
-            crossAxisAlignment: CrossAxisAlignment.start,
-            children: [
-              Text(
-                'Available Credits',
-                style: AppTypography.bodyRegular.copyWith(
-                  color: AppColors.surface.withValues(alpha: 0.8),
-                ),
-              ),
-              Text(
-                credits,
-                style: AppTypography.bodyLarge.copyWith(
-                  fontSize: 32,
-                  fontWeight: FontWeight.w700,
-                  color: AppColors.surface,
-                ),
-              ),
-            ],
-          ),
-        ],
-      ),
-    );
-  }
-}
-
-/// Video preview area - video URL from card click. Auto-load and play on init.
-/// Video fit: contain (no crop). Loading animation until ready.
-class _VideoPreviewArea extends StatefulWidget {
-  const _VideoPreviewArea({
+/// 生成页背景：有预览视频则循环播放；打开应用内相机时暂停并显示静帧，避免与 CameraPreview 冲突。
+class _GenerateBackgroundLayer extends StatefulWidget {
+  const _GenerateBackgroundLayer({
    this.videoUrl,
    this.imageUrl,
+    this.suspendVideoPlayback = false,
  });

  final String? videoUrl;
  final String? imageUrl;
+  final bool suspendVideoPlayback;

  @override
-  State<_VideoPreviewArea> createState() => _VideoPreviewAreaState();
+  State<_GenerateBackgroundLayer> createState() =>
+      _GenerateBackgroundLayerState();
 }

-class _VideoPreviewAreaState extends State<_VideoPreviewArea> {
+class _GenerateBackgroundLayerState extends State<_GenerateBackgroundLayer> {
  VideoPlayerController? _controller;
+  int _videoLoadGen = 0;
+
+  Uint8List? _videoPosterBytes;
+  bool _videoPosterLoading = false;
+
+  void _bumpVideoLoadGen() {
+    _videoLoadGen++;
+  }

  @override
  void initState() {
    super.initState();
-    if (widget.videoUrl != null && widget.videoUrl!.isNotEmpty) {
+    _loadVideoPosterIfNeeded();
+    if (!widget.suspendVideoPlayback &&
+        widget.videoUrl != null &&
+        widget.videoUrl!.isNotEmpty) {
      _loadAndPlay();
    }
  }

  @override
  void dispose() {
+    _bumpVideoLoadGen();
    _controller?.dispose();
    _controller = null;
    super.dispose();
  }

  @override
-  void didUpdateWidget(covariant _VideoPreviewArea oldWidget) {
+  void didUpdateWidget(covariant _GenerateBackgroundLayer oldWidget) {
    super.didUpdateWidget(oldWidget);
-    if (oldWidget.videoUrl != widget.videoUrl) {
+    if (oldWidget.videoUrl != widget.videoUrl ||
+        oldWidget.imageUrl != widget.imageUrl) {
+      _videoPosterBytes = null;
+      _videoPosterLoading = false;
+      _loadVideoPosterIfNeeded();
+      _bumpVideoLoadGen();
      _controller?.dispose();
      _controller = null;
-      if (widget.videoUrl != null && widget.videoUrl!.isNotEmpty) {
+      if (widget.videoUrl != null &&
+          widget.videoUrl!.isNotEmpty &&
+          !widget.suspendVideoPlayback) {
+        _loadAndPlay();
+      } else if (mounted) {
+        setState(() {});
+      }
+      return;
+    }
+    if (widget.suspendVideoPlayback != oldWidget.suspendVideoPlayback) {
+      if (widget.suspendVideoPlayback) {
+        _bumpVideoLoadGen();
+        _controller?.pause();
+        _controller?.dispose();
+        _controller = null;
+        if (mounted) setState(() {});
+      } else if (widget.videoUrl != null &&
+          widget.videoUrl!.isNotEmpty) {
        _loadAndPlay();
      }
    }
  }

+  Future<void> _loadVideoPosterIfNeeded() async {
+    final v = widget.videoUrl;
+    final img = widget.imageUrl;
+    if (v == null || v.isEmpty) return;
+    if (img != null && img.isNotEmpty) return;
+
+    if (mounted) setState(() => _videoPosterLoading = true);
+    final bytes = await VideoThumbnailCache.instance.getPosterFrame(v);
+    if (!mounted) return;
+    setState(() {
+      _videoPosterBytes = bytes;
+      _videoPosterLoading = false;
+    });
+  }
+
  Future<void> _loadAndPlay() async {
    final url = widget.videoUrl;
    if (url == null || url.isEmpty) return;
+    if (widget.suspendVideoPlayback) return;

-    setState(() {});
+    final myGen = ++_videoLoadGen;
+    if (mounted) setState(() {});

+    VideoPlayerController? created;
    try {
      final file = await DefaultCacheManager().getSingleFile(url);
-      if (!mounted) return;
-      final controller = VideoPlayerController.file(file);
-      await controller.initialize();
-      if (!mounted) return;
-      await controller.play();
-      controller.setLooping(true);
-      if (mounted) {
-        setState(() {
-          _controller = controller;
-        });
+      if (!mounted || myGen != _videoLoadGen) return;
+      created = VideoPlayerController.file(
+        file,
+        videoPlayerOptions: VideoPlayerOptions(mixWithOthers: true),
+      );
+      await created.initialize();
+      if (!mounted || myGen != _videoLoadGen) return;
+      await created.setVolume(1.0);
+      await created.setLooping(true);
+      await created.play();
+      if (!mounted || myGen != _videoLoadGen) return;
+      if (widget.suspendVideoPlayback) return;
+      final toAttach = created;
+      created = null;
+      if (!mounted || myGen != _videoLoadGen) {
+        await toAttach.dispose();
+        return;
      }
+      final previous = _controller;
+      setState(() => _controller = toAttach);
+      previous?.dispose();
    } catch (e) {
      GenerateVideoScreen._log.e('Video load failed', e);
      if (mounted) setState(() {});
+    } finally {
+      final orphan = created;
+      if (orphan != null) {
+        await orphan.dispose();
+      }
    }
  }

  @override
  Widget build(BuildContext context) {
-    final isReady = _controller != null && _controller!.value.isInitialized;
-    final hasVideo = widget.videoUrl != null && widget.videoUrl!.isNotEmpty;
-    final hasImage = widget.imageUrl != null && widget.imageUrl!.isNotEmpty;
+    final suspended = widget.suspendVideoPlayback;
+    final videoUrl = widget.videoUrl;
+    final hasVideoUrl = videoUrl != null && videoUrl.isNotEmpty;
+    final hasImageUrl = widget.imageUrl != null && widget.imageUrl!.isNotEmpty;
+    final videoReady = !suspended &&
+        _controller != null &&
+        _controller!.value.isInitialized;

-    // 图片模式：宽度=组件宽度，高度按图片宽高比自适应
-    if (!hasVideo && hasImage) {
-      return LayoutBuilder(
-        builder: (context, constraints) {
-          return Container(
-            width: constraints.maxWidth,
-            decoration: BoxDecoration(
-              color: AppColors.surfaceAlt,
-              borderRadius: BorderRadius.circular(16),
-              border: Border.all(
-                color: AppColors.border,
-                width: 1,
-              ),
-            ),
-            clipBehavior: Clip.antiAlias,
-            child: _AspectRatioImage(
-              imageUrl: widget.imageUrl!,
-              maxWidth: constraints.maxWidth,
-            ),
-          );
-        },
+    if (hasImageUrl && !hasVideoUrl) {
+      return CachedNetworkImage(
+        imageUrl: widget.imageUrl!,
+        fit: BoxFit.cover,
+        width: double.infinity,
+        height: double.infinity,
+        placeholder: (_, __) => const _BgLoadingPlaceholder(),
+        errorWidget: (_, __, ___) => const _BgErrorPlaceholder(),
      );
    }

-    // 视频模式：aspect ratio 来自视频或 16:9 占位
-    final aspectRatio = isReady &&
-            _controller!.value.size.width > 0 &&
-            _controller!.value.size.height > 0
-        ? _controller!.value.size.width / _controller!.value.size.height
-        : 16 / 9;
-
-    return LayoutBuilder(
-      builder: (context, constraints) {
-        final width = constraints.maxWidth;
-        final height = width / aspectRatio;
-
-        return Container(
-          width: width,
-          height: height,
-          decoration: BoxDecoration(
-            color: AppColors.surfaceAlt,
-            borderRadius: BorderRadius.circular(16),
-            border: Border.all(
-              color: AppColors.border,
-              width: 1,
-            ),
-          ),
-          clipBehavior: Clip.antiAlias,
-          child: Stack(
-            fit: StackFit.expand,
-            alignment: Alignment.center,
-            children: [
-              if (isReady)
-                SizedBox.expand(
-                  child: FittedBox(
-                    fit: BoxFit.contain,
-                    child: SizedBox(
-                      width: _controller!.value.size.width,
-                      height: _controller!.value.size.height,
-                      child: VideoPlayer(_controller!),
-                    ),
-                  ),
-                )
-              else if (hasImage)
-                CachedNetworkImage(
-                  imageUrl: widget.imageUrl!,
-                  fit: BoxFit.contain,
-                  width: double.infinity,
-                  height: double.infinity,
-                  placeholder: (_, __) =>
-                      const _LoadingOverlay(isLoading: true),
-                  errorWidget: (_, __, ___) =>
-                      const _LoadingOverlay(isLoading: false),
-                )
-              else
-                const _LoadingOverlay(isLoading: false),
-              if (hasVideo && !isReady)
-                const Positioned.fill(
-                  child: _LoadingOverlay(isLoading: true),
-                ),
-            ],
-          ),
+    if (suspended && hasVideoUrl) {
+      if (hasImageUrl) {
+        return CachedNetworkImage(
+          imageUrl: widget.imageUrl!,
+          fit: BoxFit.cover,
+          width: double.infinity,
+          height: double.infinity,
+          placeholder: (_, __) => const _BgLoadingPlaceholder(),
+          errorWidget: (_, __, ___) => const _BgErrorPlaceholder(),
        );
-      },
-    );
+      }
+      final bytes = _videoPosterBytes;
+      if (bytes != null && bytes.isNotEmpty) {
+        return Image.memory(
+          bytes,
+          fit: BoxFit.cover,
+          width: double.infinity,
+          height: double.infinity,
+          gaplessPlayback: true,
+        );
+      }
+      if (_videoPosterLoading) {
+        return const _BgLoadingPlaceholder();
+      }
+      return const ColoredBox(color: Colors.black);
+    }
+
+    if (hasVideoUrl && videoReady) {
+      return ClipRect(
+        child: FittedBox(
+          fit: BoxFit.cover,
+          child: SizedBox(
+            width: _controller!.value.size.width,
+            height: _controller!.value.size.height,
+            child: VideoPlayer(_controller!),
+          ),
+        ),
+      );
+    }
+
+    if (hasVideoUrl && hasImageUrl) {
+      return CachedNetworkImage(
+        imageUrl: widget.imageUrl!,
+        fit: BoxFit.cover,
+        width: double.infinity,
+        height: double.infinity,
+        placeholder: (_, __) => const _BgLoadingPlaceholder(),
+        errorWidget: (_, __, ___) => const _BgErrorPlaceholder(),
+      );
+    }
+
+    if (hasVideoUrl) {
+      final bytes = _videoPosterBytes;
+      if (bytes != null && bytes.isNotEmpty) {
+        return Image.memory(
+          bytes,
+          fit: BoxFit.cover,
+          width: double.infinity,
+          height: double.infinity,
+          gaplessPlayback: true,
+        );
+      }
+      if (_videoPosterLoading) {
+        return const _BgLoadingPlaceholder();
+      }
+      return const _BgLoadingPlaceholder();
+    }
+
+    if (hasImageUrl) {
+      return CachedNetworkImage(
+        imageUrl: widget.imageUrl!,
+        fit: BoxFit.cover,
+        width: double.infinity,
+        height: double.infinity,
+        placeholder: (_, __) => const _BgLoadingPlaceholder(),
+        errorWidget: (_, __, ___) => const _BgErrorPlaceholder(),
+      );
+    }
+
+    return const _BgErrorPlaceholder();
  }
 }

-/// 图片展示：宽度=组件宽度，高度按图片宽高比自适应
-class _AspectRatioImage extends StatefulWidget {
-  const _AspectRatioImage({
-    required this.imageUrl,
-    required this.maxWidth,
-  });
-
-  final String imageUrl;
-  final double maxWidth;
-
-  @override
-  State<_AspectRatioImage> createState() => _AspectRatioImageState();
-}
-
-class _AspectRatioImageState extends State<_AspectRatioImage> {
-  double? _aspectRatio;
-  ImageStream? _stream;
-  late ImageStreamListener _listener;
-
-  @override
-  void initState() {
-    super.initState();
-    _listener = ImageStreamListener(_onImageLoaded, onError: _onImageError);
-    _resolveImage();
-  }
-
-  @override
-  void didUpdateWidget(covariant _AspectRatioImage oldWidget) {
-    super.didUpdateWidget(oldWidget);
-    if (oldWidget.imageUrl != widget.imageUrl) {
-      _stream?.removeListener(_listener);
-      _aspectRatio = null;
-      _resolveImage();
-    }
-  }
-
-  void _resolveImage() {
-    final provider = CachedNetworkImageProvider(widget.imageUrl);
-    _stream = provider.resolve(const ImageConfiguration());
-    _stream!.addListener(_listener);
-  }
-
-  void _onImageLoaded(ImageInfo info, bool sync) {
-    if (!mounted) return;
-    final w = info.image.width.toDouble();
-    final h = info.image.height.toDouble();
-    if (w > 0 && h > 0) {
-      setState(() => _aspectRatio = w / h);
-    }
-  }
-
-  void _onImageError(dynamic exception, StackTrace? stackTrace) {
-    if (mounted) setState(() => _aspectRatio = 1);
-  }
-
-  @override
-  void dispose() {
-    _stream?.removeListener(_listener);
-    super.dispose();
-  }
+class _BgLoadingPlaceholder extends StatelessWidget {
+  const _BgLoadingPlaceholder();

  @override
  Widget build(BuildContext context) {
-    final ratio = _aspectRatio ?? 1;
-    final height = widget.maxWidth / ratio;
-
-    return SizedBox(
-      width: widget.maxWidth,
-      height: height,
-      child: CachedNetworkImage(
-        imageUrl: widget.imageUrl,
-        fit: BoxFit.contain,
-        width: widget.maxWidth,
-        height: height,
-        placeholder: (_, __) => SizedBox(
-          width: widget.maxWidth,
-          height: widget.maxWidth,
-          child: const _LoadingOverlay(isLoading: true),
-        ),
-        errorWidget: (_, __, ___) => SizedBox(
-          width: widget.maxWidth,
-          height: widget.maxWidth,
-          child: const _LoadingOverlay(isLoading: false),
+    return Container(
+      color: AppColors.textPrimary,
+      alignment: Alignment.center,
+      child: const SizedBox(
+        width: 40,
+        height: 40,
+        child: CircularProgressIndicator(
+          strokeWidth: 2,
+          color: AppColors.surface,
        ),
      ),
    );
  }
 }

-class _LoadingOverlay extends StatelessWidget {
-  const _LoadingOverlay({this.isLoading = true});
-
-  final bool isLoading;
+class _BgErrorPlaceholder extends StatelessWidget {
+  const _BgErrorPlaceholder();

  @override
  Widget build(BuildContext context) {
    return Container(
-      color: AppColors.surfaceAlt,
+      color: AppColors.textPrimary,
      alignment: Alignment.center,
-      child: isLoading
-          ? const SizedBox(
-              width: 40,
-              height: 40,
-              child: CircularProgressIndicator(
-                strokeWidth: 2,
-                color: AppColors.primary,
-              ),
-            )
-          : const Icon(
-              LucideIcons.video,
-              size: 48,
-              color: AppColors.textMuted,
-            ),
+      child: Icon(
+        LucideIcons.image_off,
+        size: 56,
+        color: AppColors.surface.withValues(alpha: 0.45),
+      ),
    );
  }
 }
@ -644,7 +671,7 @@ class _ResolutionToggle extends StatelessWidget {
            'Resolution',
            style: AppTypography.bodyMedium.copyWith(
              fontSize: 14,
-              color: AppColors.textPrimary,
+              color: AppColors.surface,
              fontWeight: FontWeight.w600,
            ),
          ),
@ -685,14 +712,22 @@ class _ResolutionOption extends StatelessWidget {
        height: 36,
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        decoration: BoxDecoration(
-          color: isSelected ? AppColors.primary : AppColors.surfaceAlt,
+          color: isSelected
+              ? AppColors.primaryGlass
+              : AppColors.surface.withValues(alpha: 0.18),
          borderRadius: BorderRadius.circular(18),
-          border:
-              isSelected ? null : Border.all(color: AppColors.border, width: 1),
+          border: isSelected
+              ? Border.all(
+                  color: AppColors.primary.withValues(alpha: 0.42),
+                  width: 1)
+              : Border.all(
+                  color: AppColors.surface.withValues(alpha: 0.45),
+                  width: 1,
+                ),
          boxShadow: isSelected
              ? [
                  BoxShadow(
-                    color: AppColors.primaryShadow.withValues(alpha: 0.19),
+                    color: AppColors.primaryShadow.withValues(alpha: 0.22),
                    blurRadius: 4,
                    offset: const Offset(0, 2),
                  ),
@ -704,7 +739,9 @@ class _ResolutionOption extends StatelessWidget {
          label,
          style: AppTypography.bodyMedium.copyWith(
            fontSize: 13,
-            color: isSelected ? AppColors.surface : AppColors.textSecondary,
+            color: isSelected
+                ? AppColors.surface
+                : AppColors.surface.withValues(alpha: 0.85),
            fontWeight: isSelected ? FontWeight.w600 : FontWeight.w500,
          ),
        ),
@ -733,11 +770,15 @@ class _GenerateButton extends StatelessWidget {
        child: Container(
          height: 56,
          decoration: BoxDecoration(
-            color: AppColors.primary,
+            color: AppColors.primaryGlassEmphasis,
            borderRadius: BorderRadius.circular(16),
+            border: Border.all(
+              color: AppColors.primary.withValues(alpha: 0.45),
+              width: 1,
+            ),
            boxShadow: [
              BoxShadow(
-                color: AppColors.primaryShadow.withValues(alpha: 0.25),
+                color: AppColors.primaryShadow.withValues(alpha: 0.28),
                blurRadius: 8,
                offset: const Offset(0, 2),
              ),
--- a/lib/features/generate_video/in_app_camera_page.dart
+++ b/lib/features/generate_video/in_app_camera_page.dart
@ -0,0 +1,219 @@
+import 'package:camera/camera.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
+import 'package:permission_handler/permission_handler.dart';
+
+import '../../core/log/app_logger.dart';
+import '../../core/theme/app_colors.dart';
+import '../../core/theme/app_spacing.dart';
+
+/// 应用内拍照：不跳出系统相机 Activity，避免与 Flutter Surface / 截屏防护等叠加导致黑屏卡死。
+class InAppCameraPage extends StatefulWidget {
+  const InAppCameraPage({super.key});
+
+  static final _log = AppLogger('InAppCamera');
+
+  @override
+  State<InAppCameraPage> createState() => _InAppCameraPageState();
+}
+
+class _InAppCameraPageState extends State<InAppCameraPage> {
+  CameraController? _controller;
+  bool _initializing = true;
+  bool _capturing = false;
+  String? _error;
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((_) => _prepareCamera());
+  }
+
+  Future<void> _prepareCamera() async {
+    final status = await Permission.camera.request();
+    if (!status.isGranted) {
+      if (mounted) {
+        setState(() {
+          _initializing = false;
+          _error = 'Camera permission is required';
+        });
+      }
+      return;
+    }
+
+    try {
+      final cameras = await availableCameras();
+      if (cameras.isEmpty) {
+        if (mounted) {
+          setState(() {
+            _initializing = false;
+            _error = 'No camera available';
+          });
+        }
+        return;
+      }
+      final back = cameras.where((c) => c.lensDirection == CameraLensDirection.back);
+      final selected = back.isEmpty ? cameras.first : back.first;
+
+      final c = CameraController(
+        selected,
+        ResolutionPreset.medium,
+        enableAudio: false,
+      );
+      await c.initialize();
+      if (!mounted) {
+        await c.dispose();
+        return;
+      }
+      setState(() {
+        _controller = c;
+        _initializing = false;
+      });
+    } catch (e, st) {
+      InAppCameraPage._log.e('Camera init failed', e, st);
+      if (mounted) {
+        setState(() {
+          _initializing = false;
+          _error = 'Could not open camera';
+        });
+      }
+    }
+  }
+
+  @override
+  void dispose() {
+    _controller?.dispose();
+    super.dispose();
+  }
+
+  Future<void> _onShutter() async {
+    final c = _controller;
+    if (c == null || !c.value.isInitialized || _capturing) return;
+    setState(() => _capturing = true);
+    try {
+      final shot = await c.takePicture();
+      if (!mounted) return;
+      Navigator.of(context, rootNavigator: true).pop<String>(shot.path);
+    } catch (e, st) {
+      InAppCameraPage._log.e('takePicture failed', e, st);
+      if (mounted) setState(() => _capturing = false);
+    }
+  }
+
+  void _onClose() {
+    Navigator.of(context, rootNavigator: true).pop<String>(null);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final c = _controller;
+    final showPreview =
+        !_initializing && _error == null && c != null && c.value.isInitialized;
+
+    return Scaffold(
+      backgroundColor: Colors.black,
+      body: Stack(
+        fit: StackFit.expand,
+        children: [
+          if (showPreview)
+            Positioned.fill(
+              child: ColoredBox(
+                color: Colors.black,
+                // 勿再包一层自定义 aspect 的 SizedBox/FittedBox：[CameraPreview] 已在竖屏下使用
+                // 1/value.aspectRatio + Android [RotatedBox]，外层乱算比例会把它压扁。
+                child: Center(
+                  child: CameraPreview(c),
+                ),
+              ),
+            ),
+          SafeArea(
+            child: Stack(
+              fit: StackFit.expand,
+              children: [
+                if (_initializing)
+                  const Center(
+                    child:
+                        CircularProgressIndicator(color: AppColors.primary),
+                  )
+                else if (_error != null)
+                  Center(
+                    child: Padding(
+                      padding: const EdgeInsets.all(AppSpacing.lg),
+                      child: Column(
+                        mainAxisSize: MainAxisSize.min,
+                        children: [
+                          Icon(
+                            LucideIcons.camera_off,
+                            size: 48,
+                            color: AppColors.surface.withValues(alpha: 0.6),
+                          ),
+                          const SizedBox(height: AppSpacing.md),
+                          Text(
+                            _error!,
+                            textAlign: TextAlign.center,
+                            style: TextStyle(
+                              color: AppColors.surface.withValues(alpha: 0.85),
+                              fontSize: 15,
+                            ),
+                          ),
+                          const SizedBox(height: AppSpacing.lg),
+                          TextButton(
+                            onPressed: _onClose,
+                            child: const Text('Close'),
+                          ),
+                        ],
+                      ),
+                    ),
+                  ),
+                if (showPreview)
+                  Positioned(
+                    left: 0,
+                    right: 0,
+                    bottom: 24,
+                    child: Row(
+                      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                      children: [
+                        IconButton(
+                          onPressed: _capturing ? null : _onClose,
+                          icon: Icon(
+                            LucideIcons.x,
+                            color: AppColors.surface.withValues(alpha: 0.9),
+                            size: 28,
+                          ),
+                        ),
+                        GestureDetector(
+                          onTap: _capturing ? null : _onShutter,
+                          child: Container(
+                            width: 72,
+                            height: 72,
+                            decoration: BoxDecoration(
+                              shape: BoxShape.circle,
+                              border: Border.all(
+                                color: AppColors.surface,
+                                width: 4,
+                              ),
+                              color: AppColors.surface.withValues(alpha: 0.2),
+                            ),
+                            child: _capturing
+                                ? const Padding(
+                                    padding: EdgeInsets.all(20),
+                                    child: CircularProgressIndicator(
+                                      strokeWidth: 2,
+                                      color: AppColors.surface,
+                                    ),
+                                  )
+                                : null,
+                          ),
+                        ),
+                        const SizedBox(width: 48),
+                      ],
+                    ),
+                  ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
--- a/lib/features/generate_video/widgets/album_picker_sheet.dart
+++ b/lib/features/generate_video/widgets/album_picker_sheet.dart
@ -1,13 +1,17 @@
 import 'dart:typed_data';

+import 'package:flutter/foundation.dart'
+    show defaultTargetPlatform, kIsWeb, TargetPlatform;
 import 'package:flutter/material.dart';
 import 'package:flutter_lucide/flutter_lucide.dart';
-import 'package:image_picker/image_picker.dart';
 import 'package:photo_manager/photo_manager.dart';

 import '../../../core/theme/app_colors.dart';
 import '../../../core/theme/app_spacing.dart';

+/// [showModalBottomSheet] 返回此值时由**外层页面**调系统相机，避免 BottomSheet 与相机 Activity 叠放导致返回后黑屏/卡死。
+const String kAlbumPickerRequestCamera = '__album_picker_camera__';
+
 /// 底部弹层：首格为拍照，其余为相册图片（与常见 App 一致）
 class AlbumPickerSheet extends StatefulWidget {
  const AlbumPickerSheet({super.key});
@ -29,6 +33,8 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
  int _loadedPage = -1;
  int _totalCount = 0;
  bool _loadingMore = false;
+  /// 最近一次权限结果（用于「仅部分照片」等说明）
+  PermissionState _permissionState = PermissionState.notDetermined;

  @override
  void initState() {
@ -55,6 +61,7 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {

    final state = await PhotoManager.requestPermissionExtend();
    if (!mounted) return;
+    _permissionState = state;

    if (!state.hasAccess) {
      setState(() {
@ -78,12 +85,25 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
        _busy = false;
        _recentAlbum = null;
        _totalCount = 0;
+        _assets.clear();
+        _loadedPage = -1;
      });
      return;
    }

    _recentAlbum = paths.first;
    _totalCount = await _recentAlbum!.assetCountAsync;
+    if (!mounted) return;
+
+    if (_totalCount == 0) {
+      setState(() {
+        _assets.clear();
+        _loadedPage = -1;
+        _busy = false;
+      });
+      return;
+    }
+
    final first = await _recentAlbum!.getAssetListPaged(page: 0, size: _pageSize);
    if (!mounted) return;

@ -96,6 +116,22 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
    });
  }

+  /// iOS：系统「补充照片」面板；Android 等：打开系统设置改权限
+  Future<void> _openManagePhotoAccess() async {
+    if (!kIsWeb && defaultTargetPlatform == TargetPlatform.iOS) {
+      try {
+        await PhotoManager.presentLimited();
+      } catch (_) {
+        await PhotoManager.openSetting();
+        return;
+      }
+    } else {
+      await PhotoManager.openSetting();
+      return;
+    }
+    if (mounted) await _init();
+  }
+
  void _maybeLoadMore() {
    if (_loadingMore || _busy || _recentAlbum == null) return;
    if (_assets.length >= _totalCount) return;
@ -131,15 +167,9 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
  }

  Future<void> _onCamera() async {
-    final picker = ImagePicker();
-    final x = await picker.pickImage(
-      source: ImageSource.camera,
-      imageQuality: 85,
-    );
    if (!mounted) return;
-    if (x != null) {
-      Navigator.of(context).pop<String>(x.path);
-    }
+    // 不在弹层内调 pickImage：BottomSheet 与相机 Activity 叠加时，返回后 Surface 有概率无法恢复（全黑）。
+    Navigator.of(context).pop<String>(kAlbumPickerRequestCamera);
  }

  Future<void> _onAsset(AssetEntity e) async {
@ -148,15 +178,25 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
    if (f != null) {
      Navigator.of(context).pop<String>(f.path);
    } else if (mounted) {
+      final limited = _permissionState == PermissionState.limited;
      ScaffoldMessenger.of(context).showSnackBar(
-        const SnackBar(
-          content: Text('Could not open this photo. Try another.'),
+        SnackBar(
+          content: Text(
+            limited
+                ? 'Cannot read this photo. It may not be included in your '
+                    'current selection. Use "Manage photo access" or choose '
+                    'another image.'
+                : 'Could not open this photo. Try another.',
+          ),
          behavior: SnackBarBehavior.floating,
        ),
      );
    }
  }

+  bool get _showNoPhotosHelp =>
+      !_busy && _error == null && _totalCount == 0;
+
  static const int _crossCount = 3;
  static const double _spacing = 3;

@ -234,7 +274,18 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
                          ),
                        ),
                      )
-                    : GridView.builder(
+                    : _showNoPhotosHelp
+                        ? _NoPhotosInLibraryPanel(
+                            isLimitedAccess:
+                                _permissionState == PermissionState.limited,
+                            onManageAccess: _openManagePhotoAccess,
+                            onOpenSettings: () async {
+                              await PhotoManager.openSetting();
+                            },
+                            onRetry: _init,
+                            onUseCamera: _onCamera,
+                          )
+                        : GridView.builder(
                        controller: _scrollController,
                        cacheExtent: 220,
                        padding: EdgeInsets.fromLTRB(
@ -283,6 +334,107 @@ class _AlbumPickerSheetState extends State<AlbumPickerSheet> {
  }
 }

+/// 权限为「部分照片」或相册对本应用不可见时：引导补充选图或去设置，避免只显示相机无说明
+class _NoPhotosInLibraryPanel extends StatelessWidget {
+  const _NoPhotosInLibraryPanel({
+    required this.isLimitedAccess,
+    required this.onManageAccess,
+    required this.onOpenSettings,
+    required this.onRetry,
+    required this.onUseCamera,
+  });
+
+  final bool isLimitedAccess;
+  final Future<void> Function() onManageAccess;
+  final Future<void> Function() onOpenSettings;
+  final Future<void> Function() onRetry;
+  final Future<void> Function() onUseCamera;
+
+  @override
+  Widget build(BuildContext context) {
+    final bottom = MediaQuery.paddingOf(context).bottom;
+    return SingleChildScrollView(
+      padding: EdgeInsets.fromLTRB(
+        AppSpacing.xl,
+        AppSpacing.lg,
+        AppSpacing.xl,
+        AppSpacing.xl + bottom,
+      ),
+      child: Column(
+        children: [
+          Icon(
+            LucideIcons.folder_open,
+            size: 48,
+            color: AppColors.textSecondary.withValues(alpha: 0.9),
+          ),
+          const SizedBox(height: AppSpacing.lg),
+          Text(
+            isLimitedAccess
+                ? 'No photos shared with this app'
+                : 'No photos available',
+            textAlign: TextAlign.center,
+            style: const TextStyle(
+              fontSize: 17,
+              fontWeight: FontWeight.w600,
+              color: AppColors.textPrimary,
+            ),
+          ),
+          const SizedBox(height: AppSpacing.md),
+          Text(
+            isLimitedAccess
+                ? 'You allowed access to only some photos, or none are '
+                    'selected for this app. Add photos or change permission, '
+                    'then try again.'
+                : 'We could not load any images. Check photo access in '
+                    'Settings or try again.',
+            textAlign: TextAlign.center,
+            style: const TextStyle(
+              fontSize: 14,
+              height: 1.4,
+              color: AppColors.textSecondary,
+            ),
+          ),
+          const SizedBox(height: AppSpacing.xl),
+          SizedBox(
+            width: double.infinity,
+            child: ElevatedButton(
+              style: ElevatedButton.styleFrom(
+                backgroundColor: AppColors.primary,
+                foregroundColor: AppColors.surface,
+                minimumSize: const Size(double.infinity, 48),
+                shape: RoundedRectangleBorder(
+                  borderRadius: BorderRadius.circular(12),
+                ),
+              ),
+              onPressed: () => onManageAccess(),
+              child: Text(
+                !kIsWeb && defaultTargetPlatform == TargetPlatform.iOS
+                    ? 'Select photos'
+                    : 'Manage photo access',
+              ),
+            ),
+          ),
+          const SizedBox(height: AppSpacing.sm),
+          TextButton(
+            onPressed: () => onOpenSettings(),
+            child: const Text('Open Settings'),
+          ),
+          TextButton(
+            onPressed: () => onRetry(),
+            child: const Text('Try again'),
+          ),
+          const SizedBox(height: AppSpacing.md),
+          TextButton.icon(
+            onPressed: () => onUseCamera(),
+            icon: const Icon(LucideIcons.camera, size: 20),
+            label: const Text('Take photo with camera'),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
 class _CameraGridTile extends StatelessWidget {
  const _CameraGridTile({required this.onTap});

--- a/lib/features/home/home_screen.dart
+++ b/lib/features/home/home_screen.dart
@ -101,7 +101,10 @@ class _HomeScreenState extends State<HomeScreen> {
    _loadCategories();
  }

-  static const double _videoVisibilityThreshold = 0.15;
+  /// 与 Gallery 一致：边缘格子可见比例偏低时也应参与自动播
+  static const double _videoVisibilityThreshold = 0.08;
+  /// 凡达到阈值的格子均可播；滑出后 [VideoCard] 会释放解码器，此处仅防极端情况
+  static const int _maxConcurrentHomeVideos = 16;

  void _onGridCardVisibilityChanged(int index, VisibilityInfo info) {
    if (!mounted) return;
@ -120,16 +123,21 @@ class _HomeScreenState extends State<HomeScreen> {

  void _reconcileVisibleVideoIndicesFromDetector() {
    final tasks = _displayTasks;
-    final next = <int>{};
+    final scored = <MapEntry<int, double>>[];
    for (final e in _cardVisibleFraction.entries) {
      final i = e.key;
      if (i < 0 || i >= tasks.length) continue;
      if (e.value < _videoVisibilityThreshold) continue;
      final url = tasks[i].previewVideoUrl;
      if (url != null && url.isNotEmpty) {
-        next.add(i);
+        scored.add(MapEntry(i, e.value));
      }
    }
+    scored.sort((a, b) => b.value.compareTo(a.value));
+    final next = scored
+        .take(_maxConcurrentHomeVideos)
+        .map((e) => e.key)
+        .toSet();
    _userPausedVideoIndices.removeWhere((i) => !next.contains(i));
    if (!_setsEqual(next, _visibleVideoIndices)) {
      setState(() => _visibleVideoIndices = next);
@ -273,10 +281,17 @@ class _HomeScreenState extends State<HomeScreen> {
        });
      }
      setState(() => _tasksLoading = false);
+      // 列表替换后须强制可见性重算，否则探测器有时不回调，预览一直不播
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted && widget.isActive) _scheduleVisibilityRefresh();
+      });
    }
  }

  void _onTabChanged(CategoryItem c) {
+    if (_scrollController.hasClients) {
+      _scrollController.jumpTo(0);
+    }
    setState(() => _selectedCategory = c);
    if (c.id == kExtCategoryId) {
      setState(() {
@ -286,6 +301,9 @@ class _HomeScreenState extends State<HomeScreen> {
        _visibleVideoIndices = {};
        _cardVisibleFraction.clear();
      });
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted && widget.isActive) _scheduleVisibilityRefresh();
+      });
    } else {
      _loadTasks(c.id);
    }
@ -294,6 +312,17 @@ class _HomeScreenState extends State<HomeScreen> {
  static const _placeholderImage =
      'https://images.unsplash.com/photo-1763929272543-0df093e4f659?w=400';

+  /// 与 [GenerateVideoScreen] 默认 480P 消耗一致；不足则去充值，够才进生图页
+  void _openGeneratePage(TaskItem task) {
+    final requiredCredits = task.credits480p ?? 50;
+    final balance = UserState.credits.value ?? 0;
+    if (balance < requiredCredits) {
+      Navigator.of(context).pushNamed('/recharge');
+      return;
+    }
+    Navigator.of(context).pushNamed('/generate', arguments: task);
+  }
+
  @override
  Widget build(BuildContext context) {
    return Scaffold(
@ -342,6 +371,7 @@ class _HomeScreenState extends State<HomeScreen> {
                              AppSpacing.screenPaddingLarge,
                            ),
                            controller: _scrollController,
+                            cacheExtent: 800,
                            gridDelegate:
                                const SliverGridDelegateWithFixedCrossAxisCount(
                              crossAxisCount: 2,
@ -367,19 +397,16 @@ class _HomeScreenState extends State<HomeScreen> {
                                      _placeholderImage,
                                  videoUrl: task.previewVideoUrl,
                                  credits: credits,
-                                  isActive:
+                                  isActive: widget.isActive &&
                                      _visibleVideoIndices.contains(index) &&
-                                          !_userPausedVideoIndices
-                                              .contains(index),
+                                      !_userPausedVideoIndices
+                                          .contains(index),
                                  onPlayRequested: () => setState(() =>
                                      _userPausedVideoIndices.remove(index)),
                                  onStopRequested: () => setState(() =>
                                      _userPausedVideoIndices.add(index)),
                                  onGenerateSimilar: () =>
-                                      Navigator.of(context).pushNamed(
-                                    '/generate',
-                                    arguments: task,
-                                  ),
+                                      _openGeneratePage(task),
                                ),
                              );
                            },
--- a/lib/features/home/widgets/video_card.dart
+++ b/lib/features/home/widgets/video_card.dart
@ -72,15 +72,18 @@ class _VideoCardState extends State<VideoCard> {
  void didUpdateWidget(covariant VideoCard oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (oldWidget.isActive && !widget.isActive) {
-      _stop();
+      _releaseVideoDecoder();
    } else if (!oldWidget.isActive && widget.isActive) {
      _loadAndPlay();
    }
  }

-  void _stop() {
+  /// 仅 pause 会占用 MediaCodec；滑出网格后必须 [dispose] ExoPlayer，否则多划几次后 OMX 解码器耗尽报错。
+  void _releaseVideoDecoder() {
+    _loadGen++;
    _controller?.removeListener(_onVideoUpdate);
-    _controller?.pause();
+    _disposeController();
+    _clearBottomProgress();
    if (mounted) {
      setState(() {
        _videoOpacityTarget = false;
@ -163,7 +166,7 @@ class _VideoCardState extends State<VideoCard> {
      await _controller!.play();
      if (!mounted || gen != _loadGen) return;
      if (!widget.isActive) {
-        _stop();
+        _releaseVideoDecoder();
        return;
      }
      setState(() => _videoOpacityTarget = false);
--- a/lib/shared/widgets/credits_badge.dart
+++ b/lib/shared/widgets/credits_badge.dart
@ -10,13 +10,23 @@ class CreditsBadge extends StatelessWidget {
    super.key,
    required this.credits,
    this.onTap,
+    this.foregroundColor,
+    this.capsuleColor,
  });

  final String credits;
  final VoidCallback? onTap;
+  /// 图标与数字颜色；默认 [AppColors.primary]
+  final Color? foregroundColor;
+  /// 胶囊背景；默认 [AppColors.primaryLight]
+  final Color? capsuleColor;

  @override
  Widget build(BuildContext context) {
+    final fg = foregroundColor ?? AppColors.primary;
+    final capsule = capsuleColor ?? AppColors.primaryLight;
+    final lightOnDarkNav = foregroundColor != null;
+
    return GestureDetector(
      onTap: onTap,
      child: Container(
@ -25,28 +35,35 @@ class CreditsBadge extends StatelessWidget {
          vertical: AppSpacing.sm,
        ),
        decoration: BoxDecoration(
-          color: AppColors.primaryLight,
+          color: capsule,
          borderRadius: BorderRadius.circular(14),
-          boxShadow: [
-            BoxShadow(
-              color: AppColors.primaryShadow.withValues(alpha: 0.13),
-              blurRadius: 6,
-              offset: const Offset(0, 2),
-            ),
-          ],
+          boxShadow: lightOnDarkNav
+              ? [
+                  BoxShadow(
+                    color: Colors.black.withValues(alpha: 0.28),
+                    blurRadius: 6,
+                    offset: const Offset(0, 2),
+                  ),
+                ]
+              : [
+                  BoxShadow(
+                    color: AppColors.primaryShadow.withValues(alpha: 0.13),
+                    blurRadius: 6,
+                    offset: const Offset(0, 2),
+                  ),
+                ],
        ),
        child: Row(
          mainAxisSize: MainAxisSize.min,
          children: [
-            const Icon(LucideIcons.sparkles,
-                size: 16, color: AppColors.primary),
+            Icon(LucideIcons.sparkles, size: 16, color: fg),
            const SizedBox(width: AppSpacing.sm),
            Text(
              credits,
              style: AppTypography.bodyRegular.copyWith(
                fontSize: 14,
                fontWeight: FontWeight.w600,
-                color: AppColors.primary,
+                color: fg,
              ),
            ),
          ],
--- a/lib/shared/widgets/top_nav_bar.dart
+++ b/lib/shared/widgets/top_nav_bar.dart
@ -14,6 +14,8 @@ class TopNavBar extends StatelessWidget implements PreferredSizeWidget {
    this.showBackButton = false,
    this.onBack,
    this.onCreditsTap,
+    this.backgroundColor = AppColors.surface,
+    this.foregroundColor,
  });

  final String title;
@ -21,24 +23,35 @@ class TopNavBar extends StatelessWidget implements PreferredSizeWidget {
  final bool showBackButton;
  final VoidCallback? onBack;
  final VoidCallback? onCreditsTap;
+  /// 例如全屏背景页上叠半透明导航栏时用 [Colors.transparent]
+  final Color backgroundColor;
+  /// 标题与返回键颜色；默认 [AppColors.textPrimary]
+  final Color? foregroundColor;

  @override
  Size get preferredSize => const Size.fromHeight(56);

  @override
  Widget build(BuildContext context) {
+    final fg = foregroundColor ?? AppColors.textPrimary;
+    final titleStyle = foregroundColor != null
+        ? AppTypography.navTitle.copyWith(color: foregroundColor)
+        : AppTypography.navTitle;
+
    return Container(
      height: 56,
      padding: const EdgeInsets.symmetric(horizontal: AppSpacing.screenPadding),
-      decoration: const BoxDecoration(
-        color: AppColors.surface,
-        boxShadow: [
-          BoxShadow(
-            color: AppColors.shadowLight,
-            blurRadius: 8,
-            offset: Offset(0, 2),
-          ),
-        ],
+      decoration: BoxDecoration(
+        color: backgroundColor,
+        boxShadow: backgroundColor.a < 0.02
+            ? null
+            : const [
+                BoxShadow(
+                  color: AppColors.shadowLight,
+                  blurRadius: 8,
+                  offset: Offset(0, 2),
+                ),
+              ],
      ),
      child: Row(
        children: [
@ -46,14 +59,14 @@ class TopNavBar extends StatelessWidget implements PreferredSizeWidget {
            GestureDetector(
              onTap: onBack ?? () => Navigator.of(context).pop(),
              behavior: HitTestBehavior.opaque,
-              child: const SizedBox(
+              child: SizedBox(
                width: 40,
                height: 40,
                child: Center(
                  child: Icon(
                    LucideIcons.arrow_left,
                    size: 24,
-                    color: AppColors.textPrimary,
+                    color: fg,
                  ),
                ),
              ),
@ -63,19 +76,25 @@ class TopNavBar extends StatelessWidget implements PreferredSizeWidget {
                ? Center(
                    child: Text(
                      title,
-                      style: AppTypography.navTitle,
+                      style: titleStyle,
                    ),
                  )
                : Align(
                    alignment: Alignment.centerLeft,
                    child: Text(
                      title,
-                      style: AppTypography.navTitle,
+                      style: titleStyle,
                    ),
                  ),
          ),
          if (credits != null)
-            CreditsBadge(credits: credits!, onTap: onCreditsTap)
+            CreditsBadge(
+              credits: credits!,
+              onTap: onCreditsTap,
+              foregroundColor: foregroundColor,
+              capsuleColor:
+                  foregroundColor?.withValues(alpha: 0.22),
+            )
          else
            const SizedBox(width: 40),
        ],
--- a/pubspec.yaml
+++ b/pubspec.yaml
@ -1,7 +1,7 @@
 name: pets_hero_ai
 description: PetsHero AI Application.
 publish_to: 'none'
-version: 1.1.13+24
+version: 1.1.14+25

 environment:
  sdk: '>=3.0.0 <4.0.0'
@ -37,6 +37,9 @@ dependencies:
  android_id: ^0.5.1
  visibility_detector: ^0.4.0+2
  photo_manager: ^3.9.0
+  image: ^4.5.4
+  camera: ^0.12.0+1
+  permission_handler: ^12.0.1

 dev_dependencies:
  flutter_test:
Author	SHA1	Message	Date
ivan	2ae2c19024	修复：拍照死机问题	2026-03-29 23:53:24 +08:00
ivan	9f88b80501	优化：积分不够的时候跳转到充值页面	2026-03-29 21:06:27 +08:00
ivan	846dd5e9f5	优化：生成图片页面	2026-03-29 20:41:45 +08:00