fix: obx不能返回nil，无障碍适配

lib/plugin/pl_player/view.dart

@@ -1,7 +1,7 @@
 import 'dart:async';
 
-import 'package:audio_video_progress_bar/audio_video_progress_bar.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
 import 'package:flutter_volume_controller/flutter_volume_controller.dart';
 import 'package:font_awesome_flutter/font_awesome_flutter.dart';
 import 'package:get/get.dart';
@@ -17,6 +17,8 @@ import 'package:PiliPalaX/utils/feed_back.dart';
 import 'package:PiliPalaX/utils/storage.dart';
 import 'package:screen_brightness/screen_brightness.dart';
 
+import '../../common/widgets/audio_video_progress_bar.dart';
+import '../../utils/utils.dart';
 import 'models/bottom_progress_behavior.dart';
 import 'widgets/app_bar_ani.dart';
 import 'widgets/backward_seek.dart';
@@ -79,6 +81,11 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
   DateTime? lastFullScreenToggleTime;
   // 记录上一次音量调整值作平均，避免音量调整抖动
   double lastVolume = -1.0;
+  // 是否在调整固定进度条
+  RxBool draggingFixedProgressBar = false.obs;
+  // 阅读器限制
+  Timer? _accessibilityDebounce;
+  double _lastAnnouncedValue = -1;
 
   void onDoubleTapSeekBackward() {
     _ctr.onDoubleTapSeekBackward();
@@ -127,8 +134,8 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
         defaultValue: BtmProgresBehavior.values.first.code);
     enableQuickDouble =
         setting.get(SettingBoxKey.enableQuickDouble, defaultValue: true);
-    fullScreenGestureReverse = setting.get(SettingBoxKey.fullScreenGestureReverse,
-        defaultValue: false);
+    fullScreenGestureReverse = setting
+        .get(SettingBoxKey.fullScreenGestureReverse, defaultValue: false);
     enableBackgroundPlay =
         setting.get(SettingBoxKey.enableBackgroundPlay, defaultValue: false);
     Future.microtask(() async {
@@ -281,10 +288,8 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                       children: [
                         Obx(() {
                           return Text(
-                            _.sliderTempPosition.value.inMinutes >= 60
-                                ? printDurationWithHours(
-                                    _.sliderTempPosition.value)
-                                : printDuration(_.sliderTempPosition.value),
+                            Utils.timeFormat(
+                                _.sliderTempPosition.value.inSeconds),
                             style: textStyle,
                           );
                         }),
@@ -439,6 +444,8 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
           top: 25,
           right: 15,
           bottom: 15,
+          child: Semantics(
+            label: '双击开关播放控件，左右滑动调整进度',
             child: GestureDetector(
               onTap: () {
                 _.controls = !_.showControls.value;
@@ -448,7 +455,8 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                 if (_.videoType.value == 'live' || _.controlsLock.value) {
                   return;
                 }
-              RenderBox renderBox = _playerKey.currentContext!.findRenderObject() as RenderBox;
+                RenderBox renderBox =
+                    _playerKey.currentContext!.findRenderObject() as RenderBox;
                 final double totalWidth = renderBox.size.width;
                 final double tapPosition = details.localPosition.dx;
                 final double sectionWidth = totalWidth / 3;
@@ -479,7 +487,8 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                 // final double tapPosition = details.localPosition.dx;
                 final int curSliderPosition =
                     _.sliderPosition.value.inMilliseconds;
-              RenderBox renderBox = _playerKey.currentContext!.findRenderObject() as RenderBox;
+                RenderBox renderBox =
+                    _playerKey.currentContext!.findRenderObject() as RenderBox;
                 final double scale = 90000 / renderBox.size.width;
                 final Duration pos = Duration(
                     milliseconds:
@@ -499,16 +508,17 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
               },
               // 垂直方向 音量/亮度调节
               onVerticalDragUpdate: (DragUpdateDetails details) async {
-              RenderBox renderBox = _playerKey.currentContext!.findRenderObject() as RenderBox;
-              final double totalWidth = renderBox.size.width;
-              final double tapPosition = details.localPosition.dx;
-              final double sectionWidth = totalWidth / 3;
-              final double delta = details.delta.dy;
+                RenderBox renderBox =
+                    _playerKey.currentContext!.findRenderObject() as RenderBox;
 
                 /// 锁定时禁用
                 if (_.controlsLock.value) {
                   return;
                 }
+                final double totalWidth = renderBox.size.width;
+                final double tapPosition = details.localPosition.dx;
+                final double sectionWidth = totalWidth / 3;
+                final double delta = details.delta.dy;
                 if (lastFullScreenToggleTime != null &&
                     DateTime.now().difference(lastFullScreenToggleTime!) <
                         const Duration(milliseconds: 500)) {
@@ -529,6 +539,7 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                     lastFullScreenToggleTime = DateTime.now();
                     await widget.controller.triggerFullScreen(status: status);
                   }
+
                   if (dy > _distance && dy > threshold) {
                     // 下滑退出全屏/进入全屏
                     if (_.isFullScreen.value ^ fullScreenGestureReverse) {
@@ -546,10 +557,11 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                 } else {
                   // 右边区域 👈
                   final double level = renderBox.size.height * 0.5;
-                if(lastVolume < 0) {
+                  if (lastVolume < 0) {
                     lastVolume = _ctr.volumeValue.value;
                   }
-                final double volume = (lastVolume + _ctr.volumeValue.value - delta / level)/2;
+                  final double volume =
+                      (lastVolume + _ctr.volumeValue.value - delta / level) / 2;
                   final double result = volume.clamp(0.0, 1.0);
                   lastVolume = result;
                   setVolume(result);
@@ -558,6 +570,7 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
               onVerticalDragEnd: (DragEndDetails details) {},
             ),
           ),
+        ),
 
         // 头部、底部控制条
         SafeArea(
@@ -605,28 +618,32 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
             }
             if (defaultBtmProgressBehavior ==
                 BtmProgresBehavior.alwaysHide.code) {
-              return nil;
+              return Container();
             }
             if (defaultBtmProgressBehavior ==
                     BtmProgresBehavior.onlyShowFullScreen.code &&
                 !_.isFullScreen.value) {
-              return nil;
+              return Container();
             } else if (defaultBtmProgressBehavior ==
                     BtmProgresBehavior.onlyHideFullScreen.code &&
                 _.isFullScreen.value) {
-              return nil;
+              return Container();
             }
 
             if (_.videoType.value == 'live') {
-              return const SizedBox();
+              return Container();
             }
             if (value > max || max <= 0) {
-              return nil;
+              return Container();
             }
             return Positioned(
-              bottom: -1.5,
+                bottom: -1,
                 left: 0,
                 right: 0,
+                child: Semantics(
+                  // label: '${(value / max * 100).round()}%',
+                  value: '${(value / max * 100).round()}%',
+                  // enabled: false,
                   child: ProgressBar(
                     progress: Duration(seconds: value),
                     buffered: Duration(seconds: buffer),
@@ -637,22 +654,37 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                         Theme.of(context).colorScheme.primary.withOpacity(0.4),
                     timeLabelLocation: TimeLabelLocation.none,
                     thumbColor: colorTheme,
-                barHeight: 3,
-                thumbRadius: 0.0,
-                // onDragStart: (duration) {
-                //   _.onChangedSliderStart();
-                // },
-                // onDragEnd: () {
-                //   _.onChangedSliderEnd();
-                // },
-                // onDragUpdate: (details) {
-                //   print(details);
-                // },
-                // onSeek: (duration) {
-                //   feedBack();
-                //   _.onChangedSlider(duration.inSeconds.toDouble());
-                //   _.seekTo(duration);
-                // },
+                    barHeight: 3.5,
+                    thumbRadius: draggingFixedProgressBar.value ? 7 : 4,
+                    onDragStart: (duration) {
+                      draggingFixedProgressBar.value = true;
+                      feedBack();
+                      _.onChangedSliderStart();
+                    },
+                    onDragUpdate: (duration) {
+                      double newProgress = duration.timeStamp.inSeconds / max;
+                      if ((newProgress - _lastAnnouncedValue).abs() > 0.02) {
+                        _accessibilityDebounce?.cancel();
+                        _accessibilityDebounce =
+                            Timer(const Duration(milliseconds: 200), () {
+                          SemanticsService.announce(
+                              "${(newProgress * 100).round()}%",
+                              TextDirection.ltr);
+                          _lastAnnouncedValue = newProgress;
+                        });
+                      }
+                      _.onUpdatedSliderProgress(duration.timeStamp);
+                    },
+                    onSeek: (duration) {
+                      draggingFixedProgressBar.value = false;
+                      _.onChangedSliderEnd();
+                      _.onChangedSlider(duration.inSeconds.toDouble());
+                      _.seekTo(Duration(seconds: duration.inSeconds),
+                          type: 'slider');
+                      SemanticsService.announce(
+                          "${(duration.inSeconds / max * 100).round()}%",
+                          TextDirection.ltr);
+                    },
                   ),
                   // SlideTransition(
                   //     position: Tween<Offset>(
@@ -663,7 +695,7 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                   //       curve: Curves.easeInOut,
                   //     )),
                   //     child: ),
-            );
+                ));
           },
         ),
 
@@ -678,6 +710,7 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
                 child: Visibility(
                   visible: _.showControls.value,
                   child: ComBtn(
+                    tooltip: _.controlsLock.value ? '解锁' : '锁定',
                     icon: Icon(
                       _.controlsLock.value
                           ? FontAwesomeIcons.lock