fix(flutter): 优化播放加载占位与主题色

lib/pages/player/player_view.dart

@@ -20,6 +20,7 @@ import '../../core/theme/app_colors.dart';
 import '../../core/theme/app_theme.dart';
 import '../../core/widgets/auth_gate.dart';
 import '../../core/widgets/download_action.dart';
+import '../../core/widgets/remote_image.dart';
 import '../../l10n/app_localizations.dart';
 import 'player_binding.dart';
 import 'player_logic.dart';
@@ -298,11 +299,7 @@ class _PlayerPageState extends State<PlayerPage> with WidgetsBindingObserver {
     return Stack(
       fit: StackFit.expand,
       children: [
-        if (!ready)
-          const ColoredBox(
-            key: Key('player-fallback-background'),
-            color: Colors.black,
-          ),
+        if (!ready) _PlayerFallbackBackground(posterUrl: drama.posterUrl),
         ?video,
         if (widget.homeMode && _chromeVisible && !logic.chromeHidden)
           Positioned.fill(
@@ -316,7 +313,10 @@ class _PlayerPageState extends State<PlayerPage> with WidgetsBindingObserver {
         // 票据三态之一：起播前正在向后端要签名地址
         if (selected && logic.ticketLoading)
           const Center(
-            child: CircularProgressIndicator(color: AppColors.blueSoft),
+            child: CircularProgressIndicator(
+              key: Key('player-ticket-loading'),
+              color: AppColors.blue,
+            ),
           ),
         // 票据三态之二：拿票失败（断网/服务异常）→ 可重试，不假装在加载
         if (selected && !logic.ticketLoading && logic.ticketError != null)
@@ -348,7 +348,10 @@ class _PlayerPageState extends State<PlayerPage> with WidgetsBindingObserver {
           ),
         if (selected && logic.session.loading)
           const Center(
-            child: CircularProgressIndicator(color: AppColors.blueSoft),
+            child: CircularProgressIndicator(
+              key: Key('player-session-loading'),
+              color: AppColors.blue,
+            ),
           ),
         if (selected && !ready && logic.session.error != null)
           Center(
@@ -550,3 +553,34 @@ class _PlayerPageState extends State<PlayerPage> with WidgetsBindingObserver {
     );
   }
 }
+
+class _PlayerFallbackBackground extends StatelessWidget {
+  const _PlayerFallbackBackground({required this.posterUrl});
+
+  final String posterUrl;
+
+  @override
+  Widget build(BuildContext context) {
+    if (posterUrl.trim().isEmpty) {
+      return const ColoredBox(
+        key: Key('player-fallback-background'),
+        color: Colors.black,
+      );
+    }
+    return Stack(
+      key: const Key('player-fallback-background'),
+      fit: StackFit.expand,
+      children: [
+        RemoteImage(
+          posterUrl,
+          key: const Key('player-fallback-cover'),
+          fit: BoxFit.cover,
+        ),
+        const ColoredBox(
+          key: Key('player-fallback-scrim'),
+          color: Color(0x66000000),
+        ),
+      ],
+    );
+  }
+}

test/player/player_fullscreen_test.dart

@@ -49,6 +49,26 @@ void main() {
     expect(tester.takeException(), isNull);
   });
 
+  testWidgets('should_fall_back_to_black_when_poster_is_empty', (tester) async {
+    await _pumpApp(
+      tester,
+      catalog: FakeCatalogRepository(dramas: const [_noCoverDrama]),
+    );
+    await _openSeriesPlayer(
+      tester,
+      cardKey: const Key('home-drama-card-no-cover-demo'),
+    );
+
+    expect(
+      tester
+          .widget<ColoredBox>(
+            find.byKey(const Key('player-fallback-background')),
+          )
+          .color,
+      Colors.black,
+    );
+  });
+
   testWidgets('should_show_center_toggle_only_when_paused', (tester) async {
     await _pumpApp(tester);
     await _openSeriesPlayer(tester);
@@ -283,9 +303,14 @@ void main() {
     );
     expect(find.byKey(const Key('player-background')), findsNothing);
     final fallback = find.byKey(const Key('player-fallback-background'));
-    if (fallback.evaluate().isNotEmpty) {
-      expect(tester.widget<ColoredBox>(fallback).color, Colors.black);
-    }
+    expect(fallback, findsOneWidget);
+    expect(find.byKey(const Key('player-fallback-cover')), findsOneWidget);
+    expect(
+      tester
+          .widget<ColoredBox>(find.byKey(const Key('player-fallback-scrim')))
+          .color,
+      const Color(0x66000000),
+    );
     expect(
       tester
           .widget<Scaffold>(find.byKey(const Key('player-scaffold')))
@@ -1024,3 +1049,20 @@ const _lockedDrama = Drama(
     ),
   ],
 );
+
+const _noCoverDrama = Drama(
+  id: 'no-cover-demo',
+  title: 'No Cover Demo',
+  synopsis: 'No cover synopsis',
+  posterUrl: '',
+  detailLoaded: true,
+  episodes: [
+    Episode(
+      id: 'no-cover-demo-1',
+      number: 1,
+      title: 'No Cover Episode',
+      isFree: true,
+      videoUrl: 'https://example.test/no-cover-demo-1.mp4',
+    ),
+  ],
+);