Control over shuffle order.

just_audio/android/src/main/java/com/ryanheise/just_audio/AudioPlayer.java

@@ -80,8 +80,6 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
     private Integer audioSessionId;
     private MediaSource mediaSource;
     private Integer currentIndex;
-    private Map<LoopingMediaSource, MediaSource> loopingChildren = new HashMap<>();
-    private Map<LoopingMediaSource, Integer> loopingCounts = new HashMap<>();
     private final Handler handler = new Handler();
     private final Runnable bufferWatcher = new Runnable() {
         @Override
@@ -321,6 +319,10 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
                 setShuffleModeEnabled((Integer) request.get("shuffleMode") == 1);
                 result.success(new HashMap<String, Object>());
                 break;
+            case "setShuffleOrder":
+                setShuffleOrder(request.get("audioSource"));
+                result.success(new HashMap<String, Object>());
+                break;
             case "setAutomaticallyWaitsToMinimizeStalling":
                 result.success(new HashMap<String, Object>());
                 break;
@@ -332,14 +334,20 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
             case "concatenatingInsertAll":
                 concatenating(request.get("id"))
                         .addMediaSources((Integer)request.get("index"), getAudioSources(request.get("children")), handler, () -> result.success(new HashMap<String, Object>()));
+                concatenating(request.get("id"))
+                        .setShuffleOrder(decodeShuffleOrder((List<Integer>)request.get("shuffleOrder")));
                 break;
             case "concatenatingRemoveRange":
                 concatenating(request.get("id"))
                         .removeMediaSourceRange((Integer)request.get("startIndex"), (Integer)request.get("endIndex"), handler, () -> result.success(new HashMap<String, Object>()));
+                concatenating(request.get("id"))
+                        .setShuffleOrder(decodeShuffleOrder((List<Integer>)request.get("shuffleOrder")));
                 break;
             case "concatenatingMove":
                 concatenating(request.get("id"))
                         .moveMediaSource((Integer)request.get("currentIndex"), (Integer)request.get("newIndex"), handler, () -> result.success(new HashMap<String, Object>()));
+                concatenating(request.get("id"))
+                        .setShuffleOrder(decodeShuffleOrder((List<Integer>)request.get("shuffleOrder")));
                 break;
             case "setAndroidAudioAttributes":
                 setAudioAttributes((Integer)request.get("contentType"), (Integer)request.get("flags"), (Integer)request.get("usage"));
@@ -358,39 +366,12 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
         }
     }
 
-    // Set the shuffle order for mediaSource, with currentIndex at
+    private ShuffleOrder decodeShuffleOrder(List<Integer> indexList) {
-    // the first position. Traverse the tree incrementing index at each
+        int[] shuffleIndices = new int[indexList.size()];
-    // node.
+        for (int i = 0; i < shuffleIndices.length; i++) {
-    private int setShuffleOrder(MediaSource mediaSource, int index) {
+            shuffleIndices[i] = indexList.get(i);
-        if (mediaSource instanceof ConcatenatingMediaSource) {
-            final ConcatenatingMediaSource source = (ConcatenatingMediaSource)mediaSource;
-            // Find which child is current
-            Integer currentChildIndex = null;
-            for (int i = 0; i < source.getSize(); i++) {
-                final int indexBefore = index;
-                final MediaSource child = source.getMediaSource(i);
-                index = setShuffleOrder(child, index);
-                // If currentIndex falls within this child, make this child come first.
-                if (currentIndex >= indexBefore && currentIndex < index) {
-                    currentChildIndex = i;
         }
-            }
+        return new DefaultShuffleOrder(shuffleIndices, random.nextLong());
-            // Shuffle so that the current child is first in the shuffle order
-            source.setShuffleOrder(createShuffleOrder(source.getSize(), currentChildIndex));
-        } else if (mediaSource instanceof LoopingMediaSource) {
-            final LoopingMediaSource source = (LoopingMediaSource)mediaSource;
-            // The ExoPlayer API doesn't provide accessors for these so we have
-            // to index them ourselves.
-            MediaSource child = loopingChildren.get(source);
-            int count = loopingCounts.get(source);
-            for (int i = 0; i < count; i++) {
-                index = setShuffleOrder(child, index);
-            }
-        } else {
-            // An actual media item takes up one spot in the playlist.
-            index++;
-        }
-        return index;
     }
 
     private static int[] shuffle(int length, Integer firstIndex) {
@@ -423,6 +404,26 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
         return (ConcatenatingMediaSource)mediaSources.get((String)index);
     }
 
+    private void setShuffleOrder(final Object json) {
+        Map<?, ?> map = (Map<?, ?>)json;
+        String id = (String)map.get("id");
+        MediaSource mediaSource = mediaSources.get(id);
+        if (mediaSource == null) return;
+        switch ((String)map.get("type")) {
+        case "concatenating":
+            ConcatenatingMediaSource concatenatingMediaSource = (ConcatenatingMediaSource)mediaSource;
+            concatenatingMediaSource.setShuffleOrder(decodeShuffleOrder((List<Integer>)map.get("shuffleOrder")));
+            List<Object> children = (List<Object>)map.get("children");
+            for (Object child : children) {
+                setShuffleOrder(child);
+            }
+            break;
+        case "looping":
+            setShuffleOrder(map.get("child"));
+            break;
+        }
+    }
+
     private MediaSource getAudioSource(final Object json) {
         Map<?, ?> map = (Map<?, ?>)json;
         String id = (String)map.get("id");
@@ -455,7 +456,7 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
             return new ConcatenatingMediaSource(
                     false, // isAtomic
                     (Boolean)map.get("useLazyPreparation"),
-                    new DefaultShuffleOrder(mediaSources.length),
+                    decodeShuffleOrder((List<Integer>)map.get("shuffleOrder")),
                     mediaSources);
         case "clipping":
             Long start = getLong(map.get("start"));
@@ -466,11 +467,7 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
         case "looping":
             Integer count = (Integer)map.get("count");
             MediaSource looperChild = getAudioSource(map.get("child"));
-            LoopingMediaSource looper = new LoopingMediaSource(looperChild, count);
+            return new LoopingMediaSource(looperChild, count);
-            // TODO: store both in a single map
-            loopingChildren.put(looper, looperChild);
-            loopingCounts.put(looper, count);
-            return looper;
         default:
             throw new IllegalArgumentException("Unknown AudioSource type: " + map.get("type"));
         }
@@ -520,9 +517,6 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
         errorCount = 0;
         prepareResult = result;
         transition(ProcessingState.loading);
-        if (player.getShuffleModeEnabled()) {
-            setShuffleOrder(mediaSource, 0);
-        }
         this.mediaSource = mediaSource;
         player.prepare(mediaSource);
     }
@@ -669,9 +663,6 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
     }
 
     public void setShuffleModeEnabled(final boolean enabled) {
-        if (enabled) {
-            setShuffleOrder(mediaSource, 0);
-        }
         player.setShuffleModeEnabled(enabled);
     }
 
@@ -694,7 +685,6 @@ public class AudioPlayer implements MethodCallHandler, Player.EventListener, Aud
         }
         mediaSources.clear();
         mediaSource = null;
-        loopingChildren.clear();
         if (player != null) {
             player.release();
             player = null;

just_audio/darwin/Classes/AudioPlayer.m

@@ -106,6 +106,9 @@
         } else if ([@"setShuffleMode" isEqualToString:call.method]) {
             [self setShuffleModeEnabled:(BOOL)([request[@"shuffleMode"] intValue] == 1)];
             result(@{});
+        } else if ([@"setShuffleOrder" isEqualToString:call.method]) {
+            [self setShuffleOrder:(NSDictionary *)request[@"audioSources"]];
+            result(@{});
         } else if ([@"setAutomaticallyWaitsToMinimizeStalling" isEqualToString:call.method]) {
             [self setAutomaticallyWaitsToMinimizeStalling:(BOOL)[request[@"enabled"] boolValue]];
             result(@{});
@@ -115,13 +118,13 @@
                 result(@{});
             }];
         } else if ([@"concatenatingInsertAll" isEqualToString:call.method]) {
-            [self concatenatingInsertAll:(NSString *)request[@"id"] index:[request[@"index"] intValue] sources:(NSArray *)request[@"children"]];
+            [self concatenatingInsertAll:(NSString *)request[@"id"] index:[request[@"index"] intValue] sources:(NSArray *)request[@"children"] shuffleOrder:(NSArray<NSNumber *> *)request[@"shuffleOrder"]];
             result(@{});
         } else if ([@"concatenatingRemoveRange" isEqualToString:call.method]) {
-            [self concatenatingRemoveRange:(NSString *)request[@"id"] start:[request[@"startIndex"] intValue] end:[request[@"endIndex"] intValue]];
+            [self concatenatingRemoveRange:(NSString *)request[@"id"] start:[request[@"startIndex"] intValue] end:[request[@"endIndex"] intValue] shuffleOrder:(NSArray<NSNumber *> *)request[@"shuffleOrder"]];
             result(@{});
         } else if ([@"concatenatingMove" isEqualToString:call.method]) {
-            [self concatenatingMove:(NSString *)request[@"id"] currentIndex:[request[@"currentIndex"] intValue] newIndex:[request[@"newIndex"] intValue]];
+            [self concatenatingMove:(NSString *)request[@"id"] currentIndex:[request[@"currentIndex"] intValue] newIndex:[request[@"newIndex"] intValue] shuffleOrder:(NSArray<NSNumber *> *)request[@"shuffleOrder"]];
             result(@{});
         } else if ([@"setAndroidAudioAttributes" isEqualToString:call.method]) {
             result(@{});
@@ -144,22 +147,7 @@
 }
 
 // Untested
-- (void)concatenatingAdd:(NSString *)catId source:(NSDictionary *)source {
+- (void)concatenatingInsertAll:(NSString *)catId index:(int)index sources:(NSArray *)sources shuffleOrder:(NSArray<NSNumber *> *)shuffleOrder {
-    [self concatenatingInsertAll:catId index:-1 sources:@[source]];
-}
-
-// Untested
-- (void)concatenatingInsert:(NSString *)catId index:(int)index source:(NSDictionary *)source {
-    [self concatenatingInsertAll:catId index:index sources:@[source]];
-}
-
-// Untested
-- (void)concatenatingAddAll:(NSString *)catId sources:(NSArray *)sources {
-    [self concatenatingInsertAll:catId index:-1 sources:sources];
-}
-
-// Untested
-- (void)concatenatingInsertAll:(NSString *)catId index:(int)index sources:(NSArray *)sources {
     // Find all duplicates of the identified ConcatenatingAudioSource.
     NSMutableArray *matches = [[NSMutableArray alloc] init];
     [_audioSource findById:catId matches:matches];
@@ -172,6 +160,7 @@
             AudioSource *audioSource = audioSources[j];
             [catSource insertSource:audioSource atIndex:(idx + j)];
         }
+        [catSource setShuffleOrder:shuffleOrder];
     }
     // Index the new audio sources.
     _indexedAudioSources = [[NSMutableArray alloc] init];
@@ -200,12 +189,7 @@
 }
 
 // Untested
-- (void)concatenatingRemoveAt:(NSString *)catId index:(int)index {
+- (void)concatenatingRemoveRange:(NSString *)catId start:(int)start end:(int)end shuffleOrder:(NSArray<NSNumber *> *)shuffleOrder {
-    [self concatenatingRemoveRange:catId start:index end:(index + 1)];
-}
-
-// Untested
-- (void)concatenatingRemoveRange:(NSString *)catId start:(int)start end:(int)end {
     // Find all duplicates of the identified ConcatenatingAudioSource.
     NSMutableArray *matches = [[NSMutableArray alloc] init];
     [_audioSource findById:catId matches:matches];
@@ -214,6 +198,7 @@
         ConcatenatingAudioSource *catSource = (ConcatenatingAudioSource *)matches[i];
         int endIndex = end >= 0 ? end : catSource.count;
         [catSource removeSourcesFromIndex:start toIndex:endIndex];
+        [catSource setShuffleOrder:shuffleOrder];
     }
     // Re-index the remaining audio sources.
     NSArray<IndexedAudioSource *> *oldIndexedAudioSources = _indexedAudioSources;
@@ -239,7 +224,7 @@
 }
 
 // Untested
-- (void)concatenatingMove:(NSString *)catId currentIndex:(int)currentIndex newIndex:(int)newIndex {
+- (void)concatenatingMove:(NSString *)catId currentIndex:(int)currentIndex newIndex:(int)newIndex shuffleOrder:(NSArray<NSNumber *> *)shuffleOrder {
     // Find all duplicates of the identified ConcatenatingAudioSource.
     NSMutableArray *matches = [[NSMutableArray alloc] init];
     [_audioSource findById:catId matches:matches];
@@ -247,6 +232,7 @@
     for (int i = 0; i < matches.count; i++) {
         ConcatenatingAudioSource *catSource = (ConcatenatingAudioSource *)matches[i];
         [catSource moveSourceFromIndex:currentIndex toIndex:newIndex];
+        [catSource setShuffleOrder:shuffleOrder];
     }
     // Re-index the audio sources.
     _indexedAudioSources = [[NSMutableArray alloc] init];
@@ -256,11 +242,6 @@
     [self broadcastPlaybackEvent];
 }
 
-// Untested
-- (void)concatenatingClear:(NSString *)catId {
-    [self concatenatingRemoveRange:catId start:0 end:-1];
-}
-
 - (FlutterError*)onListenWithArguments:(id)arguments eventSink:(FlutterEventSink)eventSink {
     _eventSink = eventSink;
     return nil;
@@ -408,7 +389,8 @@
         return [[UriAudioSource alloc] initWithId:data[@"id"] uri:data[@"uri"]];
     } else if ([@"concatenating" isEqualToString:type]) {
         return [[ConcatenatingAudioSource alloc] initWithId:data[@"id"]
-                                               audioSources:[self decodeAudioSources:data[@"children"]]];
+                                               audioSources:[self decodeAudioSources:data[@"children"]]
+                                               shuffleOrder:(NSArray<NSNumber *> *)data[@"shuffleOrder"]];
     } else if ([@"clipping" isEqualToString:type]) {
         return [[ClippingAudioSource alloc] initWithId:data[@"id"]
                                            audioSource:(UriAudioSource *)[self decodeAudioSource:data[@"child"]]
@@ -590,15 +572,12 @@
 }
 
 - (void)updateOrder {
-    if (_shuffleModeEnabled) {
-        [_audioSource shuffle:0 currentIndex: _index];
-    }
     _orderInv = [NSMutableArray arrayWithCapacity:[_indexedAudioSources count]];
     for (int i = 0; i < [_indexedAudioSources count]; i++) {
         [_orderInv addObject:@(0)];
     }
     if (_shuffleModeEnabled) {
-        _order = [_audioSource getShuffleOrder];
+        _order = [_audioSource getShuffleIndices];
     } else {
         NSMutableArray *order = [[NSMutableArray alloc] init];
         for (int i = 0; i < [_indexedAudioSources count]; i++) {
@@ -1031,6 +1010,10 @@
     [self enqueueFrom:_index];
 }
 
+- (void)setShuffleOrder:(NSDictionary *)dict {
+    [_audioSource decodeShuffleOrder:dict];
+}
+
 - (void)dumpQueue {
     for (int i = 0; i < _player.items.count; i++) {
         IndexedPlayerItem *playerItem = (IndexedPlayerItem *)_player.items[i];

just_audio/darwin/Classes/AudioSource.m

@@ -26,12 +26,11 @@
     }
 }
 
-- (NSArray<NSNumber *> *)getShuffleOrder {
+- (NSArray<NSNumber *> *)getShuffleIndices {
     return @[];
 }
 
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex {
+- (void)decodeShuffleOrder:(NSDictionary *)dict {
-    return 0;
 }
 
 @end

just_audio/darwin/Classes/ClippingAudioSource.m

@@ -39,7 +39,7 @@
     return _audioSource.playerItem;
 }
 
-- (NSArray<NSNumber *> *)getShuffleOrder {
+- (NSArray<NSNumber *> *)getShuffleIndices {
     return @[@(0)];
 }
 

just_audio/darwin/Classes/ConcatenatingAudioSource.m

@@ -5,13 +5,14 @@
 
 @implementation ConcatenatingAudioSource {
     NSMutableArray<AudioSource *> *_audioSources;
-    NSMutableArray<NSNumber *> *_shuffleOrder;
+    NSArray<NSNumber *> *_shuffleOrder;
 }
 
-- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources {
+- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources shuffleOrder:(NSArray<NSNumber *> *)shuffleOrder {
     self = [super initWithId:sid];
     NSAssert(self, @"super init cannot be nil");
     _audioSources = audioSources;
+    _shuffleOrder = shuffleOrder;
     return self;
 }
 
@@ -50,19 +51,19 @@
     }
 }
 
-- (NSArray<NSNumber *> *)getShuffleOrder {
+- (NSArray<NSNumber *> *)getShuffleIndices {
     NSMutableArray<NSNumber *> *order = [NSMutableArray new];
     int offset = (int)[order count];
     NSMutableArray<NSArray<NSNumber *> *> *childOrders = [NSMutableArray new]; // array of array of ints
     for (int i = 0; i < [_audioSources count]; i++) {
         AudioSource *audioSource = _audioSources[i];
-        NSArray<NSNumber *> *childShuffleOrder = [audioSource getShuffleOrder];
+        NSArray<NSNumber *> *childShuffleIndices = [audioSource getShuffleIndices];
         NSMutableArray<NSNumber *> *offsetChildShuffleOrder = [NSMutableArray new];
-        for (int j = 0; j < [childShuffleOrder count]; j++) {
+        for (int j = 0; j < [childShuffleIndices count]; j++) {
-            [offsetChildShuffleOrder addObject:@([childShuffleOrder[j] integerValue] + offset)];
+            [offsetChildShuffleOrder addObject:@([childShuffleIndices[j] integerValue] + offset)];
         }
         [childOrders addObject:offsetChildShuffleOrder];
-        offset += [childShuffleOrder count];
+        offset += [childShuffleIndices count];
     }
     for (int i = 0; i < [_audioSources count]; i++) {
         [order addObjectsFromArray:childOrders[[_shuffleOrder[i] integerValue]]];
@@ -70,40 +71,22 @@
     return order;
 }
 
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex {
+- (void)setShuffleOrder:(NSArray<NSNumber *> *)shuffleOrder {
-    int currentChildIndex = -1;
+    _shuffleOrder = shuffleOrder;
+}
+
+- (void)decodeShuffleOrder:(NSDictionary *)dict {
+    _shuffleOrder = (NSArray<NSNumber *> *)dict[@"shuffleOrder"];
+    NSArray *dictChildren = (NSArray *)dict[@"children"];
+    if (_audioSources.count != dictChildren.count) {
+        NSLog(@"decodeShuffleOrder Concatenating children don't match");
+        return;
+    }
     for (int i = 0; i < [_audioSources count]; i++) {
-        int indexBefore = treeIndex;
         AudioSource *child = _audioSources[i];
-        treeIndex = [child shuffle:treeIndex currentIndex:currentIndex];
+        NSDictionary *dictChild = (NSDictionary *)dictChildren[i];
-        if (currentIndex >= indexBefore && currentIndex < treeIndex) {
+        [child decodesetShuffleOrder:dictChild];
-            currentChildIndex = i;
-        } else {}
     }
-    // Shuffle so that the current child is first in the shuffle order
-    _shuffleOrder = [NSMutableArray arrayWithCapacity:[_audioSources count]];
-    for (int i = 0; i < [_audioSources count]; i++) {
-        [_shuffleOrder addObject:@(0)];
-    }
-    NSLog(@"shuffle: audioSources.count=%d and shuffleOrder.count=%d", (int)[_audioSources count], (int)[_shuffleOrder count]);
-    // First generate a random shuffle
-    for (int i = 0; i < [_audioSources count]; i++) {
-        int j = arc4random_uniform(i + 1);
-        _shuffleOrder[i] = _shuffleOrder[j];
-        _shuffleOrder[j] = @(i);
-    }
-    // Then bring currentIndex to the front
-    if (currentChildIndex != -1) {
-      for (int i = 1; i < [_audioSources count]; i++) {
-        if ([_shuffleOrder[i] integerValue] == currentChildIndex) {
-          NSNumber *v = _shuffleOrder[0];
-          _shuffleOrder[0] = _shuffleOrder[i];
-          _shuffleOrder[i] = v;
-          break;
-        }
-      }
-    }
-    return treeIndex;
 }
 
 @end

just_audio/darwin/Classes/IndexedAudioSource.m

@@ -42,10 +42,6 @@
     return treeIndex + 1;
 }
 
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex {
-    return treeIndex + 1;
-}
-
 - (void)attach:(AVQueuePlayer *)player {
     _isAttached = YES;
 }

just_audio/darwin/Classes/LoopingAudioSource.m

@@ -28,12 +28,12 @@
     }
 }
 
-- (NSArray<NSNumber *> *)getShuffleOrder {
+- (NSArray<NSNumber *> *)getShuffleIndices {
     NSMutableArray<NSNumber *> *order = [NSMutableArray new];
     int offset = (int)[order count];
     for (int i = 0; i < [_audioSources count]; i++) {
         AudioSource *audioSource = _audioSources[i];
-        NSArray<NSNumber *> *childShuffleOrder = [audioSource getShuffleOrder];
+        NSArray<NSNumber *> *childShuffleOrder = [audioSource getShuffleIndices];
         for (int j = 0; j < [childShuffleOrder count]; j++) {
             [order addObject:@([childShuffleOrder[j] integerValue] + offset)];
         }
@@ -42,12 +42,12 @@
     return order;
 }
 
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex {
+- (void)decodeShuffleOrder:(NSDictionary *)dict {
-    // TODO: This should probably shuffle the same way on all duplicates.
+    NSDictionary *dictChild = (NSDictionary *)dict[@"child"];
     for (int i = 0; i < [_audioSources count]; i++) {
-        treeIndex = [_audioSources[i] shuffle:treeIndex currentIndex:currentIndex];
+        AudioSource *child = _audioSources[i];
+        [child decodeShuffleOrder:dictChild];
     }
-    return treeIndex;
 }
 
 @end

just_audio/darwin/Classes/UriAudioSource.m

@@ -35,7 +35,7 @@
     return _playerItem;
 }
 
-- (NSArray<NSNumber *> *)getShuffleOrder {
+- (NSArray<NSNumber *> *)getShuffleIndices {
     return @[@(0)];
 }
 

just_audio/example/lib/main.dart

@@ -179,8 +179,12 @@ class _MyAppState extends State<MyApp> {
                         icon: shuffleModeEnabled
                             ? Icon(Icons.shuffle, color: Colors.orange)
                             : Icon(Icons.shuffle, color: Colors.grey),
-                        onPressed: () {
+                        onPressed: () async {
-                          _player.setShuffleModeEnabled(!shuffleModeEnabled);
+                          final enable = !shuffleModeEnabled;
+                          if (enable) {
+                            await _player.shuffle();
+                          }
+                          await _player.setShuffleModeEnabled(enable);
                         },
                       );
                     },

just_audio/example/pubspec.lock

@@ -7,7 +7,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0-nullsafety.1"
+    version: "2.5.0-nullsafety.3"
   audio_session:
     dependency: "direct main"
     description:
@@ -21,35 +21,35 @@ packages:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   characters:
     dependency: transitive
     description:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.3"
+    version: "1.1.0-nullsafety.5"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   clock:
     dependency: transitive
     description:
       name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   collection:
     dependency: transitive
     description:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0-nullsafety.3"
+    version: "1.15.0-nullsafety.5"
   convert:
     dependency: transitive
     description:
@@ -77,7 +77,7 @@ packages:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   ffi:
     dependency: transitive
     description:
@@ -114,6 +114,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.16.1"
+  js:
+    dependency: transitive
+    description:
+      name: js
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.6.3-nullsafety.3"
   just_audio:
     dependency: "direct main"
     description:
@@ -124,16 +131,16 @@ packages:
   just_audio_platform_interface:
     dependency: transitive
     description:
-      name: just_audio_platform_interface
+      path: "../../just_audio_platform_interface"
-      url: "https://pub.dartlang.org"
+      relative: true
-    source: hosted
+    source: path
     version: "1.1.1"
   just_audio_web:
     dependency: transitive
     description:
-      name: just_audio_web
+      path: "../../just_audio_web"
-      url: "https://pub.dartlang.org"
+      relative: true
-    source: hosted
+    source: path
     version: "0.1.1"
   matcher:
     dependency: transitive
@@ -141,21 +148,21 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10-nullsafety.1"
+    version: "0.12.10-nullsafety.3"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.3"
+    version: "1.3.0-nullsafety.6"
   path:
     dependency: transitive
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.1"
+    version: "1.8.0-nullsafety.3"
   path_provider:
     dependency: transitive
     description:
@@ -230,49 +237,49 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.2"
+    version: "1.8.0-nullsafety.4"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.10.0-nullsafety.1"
+    version: "1.10.0-nullsafety.6"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19-nullsafety.2"
+    version: "0.2.19-nullsafety.6"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.3"
+    version: "1.3.0-nullsafety.5"
   uuid:
     dependency: transitive
     description:
@@ -286,7 +293,7 @@ packages:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.3"
+    version: "2.1.0-nullsafety.5"
   win32:
     dependency: transitive
     description:
@@ -302,5 +309,5 @@ packages:
     source: hosted
     version: "0.1.2"
 sdks:
-  dart: ">=2.10.0-110 <2.11.0"
+  dart: ">=2.12.0-0.0 <3.0.0"
   flutter: ">=1.12.13+hotfix.5 <2.0.0"

just_audio/ios/Classes/AudioSource.h

@@ -7,7 +7,7 @@
 - (instancetype)initWithId:(NSString *)sid;
 - (int)buildSequence:(NSMutableArray *)sequence treeIndex:(int)treeIndex;
 - (void)findById:(NSString *)sourceId matches:(NSMutableArray<AudioSource *> *)matches;
-- (NSArray<NSNumber *> *)getShuffleOrder;
+- (NSArray<NSNumber *> *)getShuffleIndices;
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex;
+- (void)decodeShuffleOrder:(NSDictionary *)dict;
 
 @end

just_audio/ios/Classes/ConcatenatingAudioSource.h

@@ -5,9 +5,10 @@
 
 @property (readonly, nonatomic) int count;
 
-- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources;
+- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources shuffleOrder:(NSMutableArray<NSNumber *> *)shuffleOrder;
 - (void)insertSource:(AudioSource *)audioSource atIndex:(int)index;
 - (void)removeSourcesFromIndex:(int)start toIndex:(int)end;
 - (void)moveSourceFromIndex:(int)currentIndex toIndex:(int)newIndex;
+- (void)setShuffleOrder:(NSArray<NSNumber *> *)shuffleOrder;
 
 @end

just_audio/lib/just_audio.dart

@@ -45,7 +45,7 @@ class AudioPlayer {
   bool _disposed = false;
 
   PlaybackEvent _playbackEvent;
-  final _playbackEventSubject = BehaviorSubject<PlaybackEvent>();
+  final _playbackEventSubject = BehaviorSubject<PlaybackEvent>(sync: true);
   Future<Duration> _durationFuture;
   final _durationSubject = BehaviorSubject<Duration>();
   final _processingStateSubject = BehaviorSubject<ProcessingState>();
@@ -56,7 +56,9 @@ class AudioPlayer {
   final _icyMetadataSubject = BehaviorSubject<IcyMetadata>();
   final _playerStateSubject = BehaviorSubject<PlayerState>();
   final _sequenceSubject = BehaviorSubject<List<IndexedAudioSource>>();
-  final _currentIndexSubject = BehaviorSubject<int>();
+  final _shuffleIndicesSubject = BehaviorSubject<List<int>>();
+  final _shuffleIndicesInv = <int>[];
+  final _currentIndexSubject = BehaviorSubject<int>(sync: true);
   final _sequenceStateSubject = BehaviorSubject<SequenceState>();
   final _loopModeSubject = BehaviorSubject<LoopMode>();
   final _shuffleModeEnabledSubject = BehaviorSubject<bool>();
@@ -103,19 +105,29 @@ class AudioPlayer {
         .map((event) => event.currentIndex)
         .distinct()
         .handleError((err, stack) {/* noop */}));
+    currentIndexStream.listen((index) => print('### index: $index'));
     _androidAudioSessionIdSubject.addStream(playbackEventStream
         .map((event) => event.androidAudioSessionId)
         .distinct()
         .handleError((err, stack) {/* noop */}));
-    _sequenceStateSubject.addStream(
+    _sequenceStateSubject.addStream(Rx.combineLatest5<List<IndexedAudioSource>,
-        Rx.combineLatest2<List<IndexedAudioSource>, int, SequenceState>(
+        List<int>, int, bool, LoopMode, SequenceState>(
       sequenceStream,
+      shuffleIndicesStream,
       currentIndexStream,
-      (sequence, currentIndex) {
+      shuffleModeEnabledStream,
+      loopModeStream,
+      (sequence, shuffleIndices, currentIndex, shuffleModeEnabled, loopMode) {
         if (sequence == null) return null;
         if (currentIndex == null) currentIndex = 0;
         currentIndex = min(sequence.length - 1, max(0, currentIndex));
-        return SequenceState(sequence, currentIndex);
+        return SequenceState(
+          sequence,
+          currentIndex,
+          shuffleIndices,
+          shuffleModeEnabled,
+          loopMode,
+        );
       },
     ).distinct().handleError((err, stack) {/* noop */}));
     _playerStateSubject.addStream(
@@ -125,6 +137,8 @@ class AudioPlayer {
                 (playing, event) => PlayerState(playing, event.processingState))
             .distinct()
             .handleError((err, stack) {/* noop */}));
+    _shuffleModeEnabledSubject.add(false);
+    _loopModeSubject.add(LoopMode.off);
     _platform.then((platform) {
       platform.playbackEventMessageStream.listen((message) {
         final playbackEvent = PlaybackEvent(
@@ -140,6 +154,8 @@ class AudioPlayer {
           currentIndex: message.currentIndex,
           androidAudioSessionId: message.androidAudioSessionId,
         );
+        print(
+            "### received event with currentIndex: ${playbackEvent.currentIndex}");
         _durationFuture = Future.value(playbackEvent.duration);
         if (playbackEvent.duration != _playbackEvent.duration) {
           _durationSubject.add(playbackEvent.duration);
@@ -268,6 +284,16 @@ class AudioPlayer {
   Stream<List<IndexedAudioSource>> get sequenceStream =>
       _sequenceSubject.stream;
 
+  /// The current shuffled sequence of indexed audio sources.
+  List<int> get shuffleIndices => _shuffleIndicesSubject.value;
+
+  /// A stream broadcasting the current shuffled sequence of indexed audio
+  /// sources.
+  Stream<List<int>> get shuffleIndicesStream => _shuffleIndicesSubject.stream;
+
+  //List<IndexedAudioSource> get _effectiveSequence =>
+  //    shuffleModeEnabled ? shuffleIndices : sequence;
+
   /// The index of the current item.
   int get currentIndex => _currentIndexSubject.value;
 
@@ -282,14 +308,71 @@ class AudioPlayer {
   Stream<SequenceState> get sequenceStateStream => _sequenceStateSubject.stream;
 
   /// Whether there is another item after the current index.
-  bool get hasNext =>
+  bool get hasNext => _nextIndex != null;
-      _audioSource != null &&
-      currentIndex != null &&
-      currentIndex + 1 < sequence.length;
 
   /// Whether there is another item before the current index.
-  bool get hasPrevious =>
+  bool get hasPrevious => _previousIndex != null;
-      _audioSource != null && currentIndex != null && currentIndex > 0;
+
+  int get _nextIndex => _getRelativeIndex(1);
+  int get _previousIndex => _getRelativeIndex(-1);
+
+  int _getRelativeIndex(int offset) {
+    print('### _getRelativeIndex');
+    print('audioSource = $_audioSource');
+    print('currentIndex = $currentIndex');
+    print('shuffleModeEnabled = $shuffleModeEnabled');
+    if (_audioSource == null ||
+        currentIndex == null ||
+        shuffleModeEnabled == null) return null;
+    if (loopMode == LoopMode.one) return currentIndex;
+    int result;
+    print('shuffleModeEnabled: $shuffleModeEnabled');
+    if (shuffleModeEnabled) {
+      print('shuffleIndices: $shuffleIndices');
+      print('shuffleIndicesInv: $_shuffleIndicesInv');
+      if (shuffleIndices == null) return null;
+      final shufflePos = _shuffleIndicesInv[currentIndex];
+      var newShufflePos = shufflePos + offset;
+      print(
+          'newshufflePos($newShufflePos) >= shuffleIndices.length(${shuffleIndices.length})');
+      if (newShufflePos >= shuffleIndices.length) {
+        if (loopMode == LoopMode.all) {
+          newShufflePos = 0;
+        } else {
+          return null;
+        }
+      }
+      if (newShufflePos < 0) {
+        if (loopMode == LoopMode.all) {
+          newShufflePos = shuffleIndices.length - 1;
+        } else {
+          return null;
+        }
+      }
+      result = shuffleIndices[newShufflePos];
+    } else {
+      print("sequence: $sequence");
+      if (sequence == null) return null;
+      result = currentIndex + offset;
+      print("result($result >= sequence.length(${sequence.length}))");
+      if (result >= sequence.length) {
+        if (loopMode == LoopMode.all) {
+          result = 0;
+        } else {
+          return null;
+        }
+      }
+      if (result < 0) {
+        if (loopMode == LoopMode.all) {
+          result = sequence.length - 1;
+        } else {
+          return null;
+        }
+      }
+    }
+    print("returning $result");
+    return result;
+  }
 
   /// The current loop mode.
   LoopMode get loopMode => _loopModeSubject.value;
@@ -452,6 +535,7 @@ class AudioPlayer {
     if (_disposed) return null;
     try {
       _audioSource = source;
+      print("### set _audioSource = $_audioSource");
       _broadcastSequence();
       final duration = await _load(source,
           initialPosition: initialPosition, initialIndex: initialIndex);
@@ -466,7 +550,30 @@ class AudioPlayer {
   }
 
   void _broadcastSequence() {
+    print("### _broadcastSequence");
     _sequenceSubject.add(_audioSource?.sequence);
+
+    print('sequence: ${_audioSource?.sequence?.length}');
+
+    _updateShuffleIndices();
+  }
+
+  _updateShuffleIndices() {
+    _shuffleIndicesSubject.add(_audioSource?.shuffleIndices);
+    print('shuffle indices: ${_audioSource?.shuffleIndices?.length}');
+    print('shuffleIndices: ${shuffleIndices?.length}');
+    final shuffleIndicesLength = shuffleIndices?.length ?? 0;
+    if (_shuffleIndicesInv.length > shuffleIndicesLength) {
+      _shuffleIndicesInv.removeRange(
+          shuffleIndicesLength, _shuffleIndicesInv.length);
+    } else if (_shuffleIndicesInv.length < shuffleIndicesLength) {
+      _shuffleIndicesInv.addAll(
+          List.filled(shuffleIndicesLength - _shuffleIndicesInv.length, 0));
+    }
+    for (var i = 0; i < shuffleIndicesLength; i++) {
+      _shuffleIndicesInv[shuffleIndices[i]] = i;
+    }
+    print('shuffleIndicesInv: ${_shuffleIndicesInv?.length}');
   }
 
   _registerAudioSource(AudioSource source) {
@@ -475,6 +582,7 @@ class AudioPlayer {
 
   Future<Duration> _load(AudioSource source,
       {Duration initialPosition, int initialIndex}) async {
+    print("### _load with initialIndex=$initialIndex");
     try {
       if (!kIsWeb && source._requiresHeaders) {
         if (_proxy == null) {
@@ -483,6 +591,8 @@ class AudioPlayer {
         }
       }
       await source._setup(this);
+      source._shuffle(initialIndex: initialIndex ?? 0);
+      _updateShuffleIndices();
       _durationFuture = (await _platform)
           .load(LoadRequest(
             audioSourceMessage: source._toMessage(),
@@ -620,6 +730,19 @@ class AudioPlayer {
             enabled ? ShuffleModeMessage.all : ShuffleModeMessage.none));
   }
 
+  /// Recursively shuffles the children of the currently loaded [AudioSource].
+  Future<void> shuffle() async {
+    print(
+        "shuffle. _disposed: $_disposed, currentIndex: $currentIndex, _audioSource: $_audioSource");
+    if (_disposed) return;
+    if (_audioSource == null) return;
+    _audioSource._shuffle(initialIndex: currentIndex);
+    _updateShuffleIndices();
+    print("Shuffle: $shuffleIndices");
+    await (await _platform).setShuffleOrder(
+        SetShuffleOrderRequest(audioSourceMessage: _audioSource._toMessage()));
+  }
+
   /// Sets automaticallyWaitsToMinimizeStalling for AVPlayer in iOS 10.0 or later, defaults to true.
   /// Has no effect on Android clients
   Future<void> setAutomaticallyWaitsToMinimizeStalling(
@@ -657,7 +780,7 @@ class AudioPlayer {
   Future<void> seekToNext() async {
     if (_disposed) return;
     if (hasNext) {
-      await seek(Duration.zero, index: currentIndex + 1);
+      await seek(Duration.zero, index: _nextIndex);
     }
   }
 
@@ -665,7 +788,7 @@ class AudioPlayer {
   Future<void> seekToPrevious() async {
     if (_disposed) return;
     if (hasPrevious) {
-      await seek(Duration.zero, index: currentIndex - 1);
+      await seek(Duration.zero, index: _previousIndex);
     }
   }
 
@@ -694,6 +817,7 @@ class AudioPlayer {
       await (await _platform).dispose(DisposeRequest());
     }
     _audioSource = null;
+    print("### set _audioSource = $_audioSource (dispose)");
     _audioSources.values.forEach((s) => s._dispose());
     _audioSources.clear();
     _proxy?.stop();
@@ -704,6 +828,7 @@ class AudioPlayer {
     await _volumeSubject.close();
     await _speedSubject.close();
     await _sequenceSubject.close();
+    await _shuffleIndicesSubject.close();
   }
 }
 
@@ -940,10 +1065,26 @@ class SequenceState {
   /// The index of the current source in the sequence.
   final int currentIndex;
 
-  SequenceState(this.sequence, this.currentIndex);
+  /// The current shuffle order
+  final List<int> shuffleIndices;
+
+  /// Whether shuffle mode is enabled.
+  final bool shuffleModeEnabled;
+
+  /// The current loop mode.
+  final LoopMode loopMode;
+
+  SequenceState(this.sequence, this.currentIndex, this.shuffleIndices,
+      this.shuffleModeEnabled, this.loopMode);
 
   /// The current source in the sequence.
   IndexedAudioSource get currentSource => sequence[currentIndex];
+
+  /// The effective sequence. This is equivalent to [sequence]. If
+  /// [shuffleModeEnabled] is true, this is modulated by [shuffleIndices].
+  List<IndexedAudioSource> get effectiveSequence => shuffleModeEnabled
+      ? shuffleIndices.map((i) => sequence[i]).toList()
+      : sequence;
 }
 
 /// A local proxy HTTP server for making remote GET requests with headers.
@@ -1105,6 +1246,8 @@ abstract class AudioSource {
     player._registerAudioSource(this);
   }
 
+  void _shuffle({int initialIndex});
+
   @mustCallSuper
   void _dispose() {
     _player = null;
@@ -1116,6 +1259,8 @@ abstract class AudioSource {
 
   List<IndexedAudioSource> get sequence;
 
+  List<int> get shuffleIndices;
+
   @override
   int get hashCode => _id.hashCode;
 
@@ -1129,8 +1274,14 @@ abstract class IndexedAudioSource extends AudioSource {
 
   IndexedAudioSource(this.tag);
 
+  @override
+  void _shuffle({int initialIndex}) {}
+
   @override
   List<IndexedAudioSource> get sequence => [this];
+
+  @override
+  List<int> get shuffleIndices => [0];
 }
 
 /// An abstract class representing audio sources that are loaded from a URI.
@@ -1258,11 +1409,14 @@ class HlsAudioSource extends UriAudioSource {
 class ConcatenatingAudioSource extends AudioSource {
   final List<AudioSource> children;
   final bool useLazyPreparation;
+  ShuffleOrder _shuffleOrder;
 
   ConcatenatingAudioSource({
     @required this.children,
     this.useLazyPreparation = true,
-  });
+    ShuffleOrder shuffleOrder,
+  }) : _shuffleOrder = shuffleOrder ?? DefaultShuffleOrder()
+          ..insert(0, children.length);
 
   @override
   Future<void> _setup(AudioPlayer player) async {
@@ -1272,28 +1426,60 @@ class ConcatenatingAudioSource extends AudioSource {
     }
   }
 
+  @override
+  void _shuffle({int initialIndex}) {
+    int localInitialIndex;
+    // si = index in [sequence]
+    // ci = index in [children] array.
+    for (var ci = 0, si = 0; ci < children.length; ci++) {
+      final child = children[ci];
+      final childLength = child.sequence.length;
+      final initialIndexWithinThisChild = initialIndex != null &&
+          initialIndex >= si &&
+          initialIndex < si + childLength;
+      if (initialIndexWithinThisChild) {
+        localInitialIndex = ci;
+      }
+      final childInitialIndex =
+          initialIndexWithinThisChild ? (initialIndex - si) : null;
+      child._shuffle(initialIndex: childInitialIndex);
+      si += childLength;
+    }
+    print(
+        "cat _shuffle (initialIndex=$initialIndex, localInitialIndex=$localInitialIndex)");
+    _shuffleOrder.shuffle(initialIndex: localInitialIndex);
+  }
+
   /// (Untested) Appends an [AudioSource].
   Future<void> add(AudioSource audioSource) async {
     final index = children.length;
     children.add(audioSource);
+    _shuffleOrder.insert(index, 1);
     if (_player != null) {
       _player._broadcastSequence();
       await audioSource._setup(_player);
       await (await _player._platform).concatenatingInsertAll(
           ConcatenatingInsertAllRequest(
-              id: _id, index: index, children: [audioSource._toMessage()]));
+              id: _id,
+              index: index,
+              children: [audioSource._toMessage()],
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
   /// (Untested) Inserts an [AudioSource] at [index].
   Future<void> insert(int index, AudioSource audioSource) async {
     children.insert(index, audioSource);
+    _shuffleOrder.insert(index, 1);
     if (_player != null) {
       _player._broadcastSequence();
       await audioSource._setup(_player);
       await (await _player._platform).concatenatingInsertAll(
           ConcatenatingInsertAllRequest(
-              id: _id, index: index, children: [audioSource._toMessage()]));
+              id: _id,
+              index: index,
+              children: [audioSource._toMessage()],
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
@@ -1301,6 +1487,7 @@ class ConcatenatingAudioSource extends AudioSource {
   Future<void> addAll(List<AudioSource> children) async {
     int index = this.children.length;
     this.children.addAll(children);
+    _shuffleOrder.insert(index, children.length);
     if (_player != null) {
       _player._broadcastSequence();
       for (var child in children) {
@@ -1310,13 +1497,15 @@ class ConcatenatingAudioSource extends AudioSource {
           ConcatenatingInsertAllRequest(
               id: _id,
               index: index,
-              children: children.map((child) => child._toMessage()).toList()));
+              children: children.map((child) => child._toMessage()).toList(),
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
   /// (Untested) Insert multiple [AudioSource]s at [index].
   Future<void> insertAll(int index, List<AudioSource> children) async {
     this.children.insertAll(index, children);
+    _shuffleOrder.insert(index, children.length);
     if (_player != null) {
       _player._broadcastSequence();
       for (var child in children) {
@@ -1326,7 +1515,8 @@ class ConcatenatingAudioSource extends AudioSource {
           ConcatenatingInsertAllRequest(
               id: _id,
               index: index,
-              children: children.map((child) => child._toMessage()).toList()));
+              children: children.map((child) => child._toMessage()).toList(),
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
@@ -1334,11 +1524,15 @@ class ConcatenatingAudioSource extends AudioSource {
   /// [ConcatenatingAudioSource] has already been loaded.
   Future<void> removeAt(int index) async {
     children.removeAt(index);
+    _shuffleOrder.removeRange(index, index + 1);
     if (_player != null) {
       _player._broadcastSequence();
       await (await _player._platform).concatenatingRemoveRange(
           ConcatenatingRemoveRangeRequest(
-              id: _id, startIndex: index, endIndex: index + 1));
+              id: _id,
+              startIndex: index,
+              endIndex: index + 1,
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
@@ -1346,33 +1540,46 @@ class ConcatenatingAudioSource extends AudioSource {
   /// to [end] exclusive.
   Future<void> removeRange(int start, int end) async {
     children.removeRange(start, end);
+    _shuffleOrder.removeRange(start, end);
     if (_player != null) {
       _player._broadcastSequence();
       await (await _player._platform).concatenatingRemoveRange(
           ConcatenatingRemoveRangeRequest(
-              id: _id, startIndex: start, endIndex: end));
+              id: _id,
+              startIndex: start,
+              endIndex: end,
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
   /// (Untested) Moves an [AudioSource] from [currentIndex] to [newIndex].
   Future<void> move(int currentIndex, int newIndex) async {
     children.insert(newIndex, children.removeAt(currentIndex));
+    _shuffleOrder.removeRange(currentIndex, currentIndex + 1);
+    _shuffleOrder.insert(newIndex, 1);
     if (_player != null) {
       _player._broadcastSequence();
       await (await _player._platform).concatenatingMove(
           ConcatenatingMoveRequest(
-              id: _id, currentIndex: currentIndex, newIndex: newIndex));
+              id: _id,
+              currentIndex: currentIndex,
+              newIndex: newIndex,
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
   /// (Untested) Removes all [AudioSources].
   Future<void> clear() async {
     children.clear();
+    _shuffleOrder.clear();
     if (_player != null) {
       _player._broadcastSequence();
       await (await _player._platform).concatenatingRemoveRange(
           ConcatenatingRemoveRangeRequest(
-              id: _id, startIndex: 0, endIndex: children.length));
+              id: _id,
+              startIndex: 0,
+              endIndex: children.length,
+              shuffleOrder: _shuffleOrder.indices));
     }
   }
 
@@ -1385,6 +1592,25 @@ class ConcatenatingAudioSource extends AudioSource {
   List<IndexedAudioSource> get sequence =>
       children.expand((s) => s.sequence).toList();
 
+  @override
+  List<int> get shuffleIndices {
+    var offset = 0;
+    final childIndicesList = <List<int>>[];
+    for (var child in children) {
+      final childIndices = child.shuffleIndices.map((i) => i + offset).toList();
+      childIndicesList.add(childIndices);
+      offset += childIndices.length;
+    }
+    final indices = <int>[];
+    for (var index in _shuffleOrder.indices) {
+      final childIndices = childIndicesList[index];
+      //print("child indices: $childIndices");
+      indices.addAll(childIndices);
+    }
+    print("### returning: $indices");
+    return indices;
+  }
+
   @override
   bool get _requiresHeaders =>
       children.any((source) => source._requiresHeaders);
@@ -1393,7 +1619,8 @@ class ConcatenatingAudioSource extends AudioSource {
   AudioSourceMessage _toMessage() => ConcatenatingAudioSourceMessage(
       id: _id,
       children: children.map((child) => child._toMessage()).toList(),
-      useLazyPreparation: useLazyPreparation);
+      useLazyPreparation: useLazyPreparation,
+      shuffleOrder: _shuffleOrder.indices);
 }
 
 /// An [AudioSource] that clips the audio of a [UriAudioSource] between a
@@ -1449,10 +1676,16 @@ class LoopingAudioSource extends AudioSource {
     await child._setup(player);
   }
 
+  @override
+  void _shuffle({int initialIndex}) {}
+
   @override
   List<IndexedAudioSource> get sequence =>
       List.generate(count, (i) => child).expand((s) => s.sequence).toList();
 
+  @override
+  List<int> get shuffleIndices => List.generate(count, (i) => i);
+
   @override
   bool get _requiresHeaders => child._requiresHeaders;
 
@@ -1461,4 +1694,90 @@ class LoopingAudioSource extends AudioSource {
       id: _id, child: child._toMessage(), count: count);
 }
 
+/// Defines the algorithm for shuffling the order of a
+/// [ConcatenatingAudioSource]. See [DefaultShuffleOrder] for a default
+/// implementation.
+abstract class ShuffleOrder {
+  /// The shuffled list of indices of [AudioSource]s to play. For example,
+  /// [2,0,1] specifies to play the 3rd, then the 1st, then the 2nd item.
+  List<int> get indices;
+
+  /// Shuffles the [indices]. If [initialIndex] is provided, the [indices]
+  /// should be shuffled so that [initialIndex] appears in `indices[0]`.
+  void shuffle({int initialIndex});
+
+  /// Inserts [count] new consecutive indices starting from [index] into
+  /// [indices], at random positions.
+  void insert(int index, int count);
+
+  /// Removes the indices that are `>= start` and `< end`.
+  void removeRange(int start, int end);
+
+  /// Removes all indices.
+  void clear();
+}
+
+/// A default implementation of [ShuffleOrder].
+class DefaultShuffleOrder extends ShuffleOrder {
+  final _random;
+  @override
+  final indices = <int>[];
+
+  DefaultShuffleOrder({Random random}) : _random = random ?? Random();
+
+  @override
+  void shuffle({int initialIndex}) {
+    assert(initialIndex == null || indices.contains(initialIndex));
+    print(
+        "### order shuffle, initialIndex: $initialIndex (existing: $indices)");
+    if (indices.length <= 1) return;
+    indices.shuffle(_random);
+    print("now $indices");
+    if (initialIndex == null) return;
+
+    final initialPos = 0;
+    final swapPos = indices.indexOf(initialIndex);
+    // Swap the indices at initialPos and swapPos.
+    final swapIndex = indices[initialPos];
+    indices[initialPos] = initialIndex;
+    indices[swapPos] = swapIndex;
+    print("final $indices");
+  }
+
+  @override
+  void insert(int index, int count) {
+    // Offset indices after insertion point.
+    for (var i = 0; i < indices.length; i++) {
+      if (indices[i] >= index) {
+        indices[i] += count;
+      }
+    }
+    // Insert new indices at random positions after currentIndex.
+    final newIndices = List.generate(count, (i) => index + i);
+    for (var newIndex in newIndices) {
+      final insertionIndex = _random.nextInt(indices.length + 1);
+      indices.insert(insertionIndex, newIndex);
+    }
+  }
+
+  @override
+  void removeRange(int start, int end) {
+    final count = end - start;
+    // Remove old indices.
+    final oldIndices = List.generate(count, (i) => start + i).toSet();
+    indices.removeWhere(oldIndices.contains);
+    // Offset indices after deletion point.
+    for (var i = 0; i < indices.length; i++) {
+      if (indices[i] >= end) {
+        indices[i] -= count;
+      }
+    }
+  }
+
+  @override
+  void clear() {
+    indices.clear();
+  }
+}
+
 enum LoopMode { off, one, all }

just_audio/macos/Classes/AudioSource.h

@@ -7,7 +7,7 @@
 - (instancetype)initWithId:(NSString *)sid;
 - (int)buildSequence:(NSMutableArray *)sequence treeIndex:(int)treeIndex;
 - (void)findById:(NSString *)sourceId matches:(NSMutableArray<AudioSource *> *)matches;
-- (NSArray<NSNumber *> *)getShuffleOrder;
+- (NSArray<NSNumber *> *)getShuffleIndices;
-- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex;
+- (void)decodeShuffleOrder:(NSDictionary *)dict;
 
 @end

just_audio/macos/Classes/ConcatenatingAudioSource.h

@@ -5,9 +5,10 @@
 
 @property (readonly, nonatomic) int count;
 
-- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources;
+- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources shuffleOrder:(NSMutableArray<NSNumber *> *)shuffleOrder;
 - (void)insertSource:(AudioSource *)audioSource atIndex:(int)index;
 - (void)removeSourcesFromIndex:(int)start toIndex:(int)end;
 - (void)moveSourceFromIndex:(int)currentIndex toIndex:(int)newIndex;
+- (void)setShuffleOrder:(NSArray<NSNumber *> *)shuffleOrder;
 
 @end

just_audio/pubspec.lock

@@ -28,7 +28,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0-nullsafety.1"
+    version: "2.5.0-nullsafety.3"
   audio_session:
     dependency: "direct main"
     description:
@@ -42,7 +42,7 @@ packages:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   build:
     dependency: transitive
     description:
@@ -70,14 +70,14 @@ packages:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.3"
+    version: "1.1.0-nullsafety.5"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   cli_util:
     dependency: transitive
     description:
@@ -91,7 +91,7 @@ packages:
       name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   code_builder:
     dependency: transitive
     description:
@@ -105,7 +105,7 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0-nullsafety.3"
+    version: "1.15.0-nullsafety.5"
   convert:
     dependency: transitive
     description:
@@ -133,7 +133,7 @@ packages:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   ffi:
     dependency: transitive
     description:
@@ -190,20 +190,20 @@ packages:
       name: js
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.6.2"
+    version: "0.6.3-nullsafety.3"
   just_audio_platform_interface:
     dependency: "direct main"
     description:
-      name: just_audio_platform_interface
+      path: "../just_audio_platform_interface"
-      url: "https://pub.dartlang.org"
+      relative: true
-    source: hosted
+    source: path
     version: "1.1.1"
   just_audio_web:
     dependency: "direct main"
     description:
-      name: just_audio_web
+      path: "../just_audio_web"
-      url: "https://pub.dartlang.org"
+      relative: true
-    source: hosted
+    source: path
     version: "0.1.1"
   logging:
     dependency: transitive
@@ -218,14 +218,14 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10-nullsafety.1"
+    version: "0.12.10-nullsafety.3"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.3"
+    version: "1.3.0-nullsafety.6"
   mockito:
     dependency: "direct dev"
     description:
@@ -260,7 +260,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.1"
+    version: "1.8.0-nullsafety.3"
   path_provider:
     dependency: "direct main"
     description:
@@ -363,49 +363,49 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.2"
+    version: "1.8.0-nullsafety.4"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.10.0-nullsafety.1"
+    version: "1.10.0-nullsafety.6"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19-nullsafety.2"
+    version: "0.2.19-nullsafety.6"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.3"
+    version: "1.3.0-nullsafety.5"
   uuid:
     dependency: "direct main"
     description:
@@ -419,7 +419,7 @@ packages:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.3"
+    version: "2.1.0-nullsafety.5"
   watcher:
     dependency: transitive
     description:
@@ -449,5 +449,5 @@ packages:
     source: hosted
     version: "2.2.1"
 sdks:
-  dart: ">=2.10.0 <2.11.0"
+  dart: ">=2.12.0-0.0 <3.0.0"
   flutter: ">=1.12.13+hotfix.5 <2.0.0"

just_audio/pubspec.yaml

@@ -8,8 +8,13 @@ environment:
   flutter: ">=1.12.13+hotfix.5"
 
 dependencies:
-  just_audio_platform_interface: ^1.1.1
+  # TODO: change this back when the new platform interface is published.
-  just_audio_web: ^0.1.1
+  # just_audio_platform_interface: ^1.1.1
+  just_audio_platform_interface:
+    path: ../just_audio_platform_interface
+  # just_audio_web: ^0.1.1
+  just_audio_web:
+    path: ../just_audio_web
   audio_session: ^0.0.9
   rxdart: ^0.24.1
   path: ^1.6.4

just_audio/test/just_audio_test.dart

@@ -1,6 +1,7 @@
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
+import 'dart:math';
 import 'dart:typed_data';
 
 import 'package:flutter/services.dart';
@@ -44,6 +45,12 @@ void runTests() {
     }
   }
 
+  void checkIndices(List<int> indices, int length) {
+    expect(indices.length, length);
+    final sorted = List.of(indices)..sort();
+    expect(sorted, equals(List.generate(indices.length, (i) => i)));
+  }
+
   setUp(() {
     audioSessionChannel.setMockMethodCallHandler((MethodCall methodCall) async {
       return null;
@@ -381,6 +388,95 @@ void runTests() {
     expect(AudioSource.uri(Uri.parse('https://a.a/a#.mpd')) is DashAudioSource,
         equals(true));
   });
+
+  test('shuffle order', () async {
+    final shuffleOrder1 = DefaultShuffleOrder(random: Random(1001));
+    checkIndices(shuffleOrder1.indices, 0);
+    //expect(shuffleOrder1.indices, equals([]));
+    shuffleOrder1.insert(0, 5);
+    //expect(shuffleOrder1.indices, equals([3, 0, 2, 4, 1]));
+    checkIndices(shuffleOrder1.indices, 5);
+    shuffleOrder1.insert(3, 2);
+    checkIndices(shuffleOrder1.indices, 7);
+    shuffleOrder1.insert(0, 2);
+    checkIndices(shuffleOrder1.indices, 9);
+    shuffleOrder1.insert(9, 2);
+    checkIndices(shuffleOrder1.indices, 11);
+
+    final indices1 = List.of(shuffleOrder1.indices);
+    shuffleOrder1.shuffle();
+    expect(shuffleOrder1.indices, isNot(indices1));
+    checkIndices(shuffleOrder1.indices, 11);
+    final indices2 = List.of(shuffleOrder1.indices);
+    shuffleOrder1.shuffle(initialIndex: 5);
+    expect(shuffleOrder1.indices[0], equals(5));
+    expect(shuffleOrder1.indices, isNot(indices2));
+    checkIndices(shuffleOrder1.indices, 11);
+
+    shuffleOrder1.removeRange(4, 6);
+    checkIndices(shuffleOrder1.indices, 9);
+    shuffleOrder1.removeRange(0, 2);
+    checkIndices(shuffleOrder1.indices, 7);
+    shuffleOrder1.removeRange(5, 7);
+    checkIndices(shuffleOrder1.indices, 5);
+    shuffleOrder1.removeRange(0, 5);
+    checkIndices(shuffleOrder1.indices, 0);
+
+    shuffleOrder1.insert(0, 5);
+    checkIndices(shuffleOrder1.indices, 5);
+    shuffleOrder1.clear();
+    checkIndices(shuffleOrder1.indices, 0);
+  });
+
+  test('shuffle', () async {
+    AudioSource createSource() => ConcatenatingAudioSource(
+          shuffleOrder: DefaultShuffleOrder(random: Random(1001)),
+          children: [
+            LoopingAudioSource(
+              count: 2,
+              child: ClippingAudioSource(
+                start: Duration(seconds: 60),
+                end: Duration(seconds: 65),
+                child: AudioSource.uri(Uri.parse("https://foo.foo/foo.mp3")),
+                tag: 'a',
+              ),
+            ),
+            AudioSource.uri(
+              Uri.parse("https://bar.bar/bar.mp3"),
+              tag: 'b',
+            ),
+            AudioSource.uri(
+              Uri.parse("https://baz.baz/baz.mp3"),
+              tag: 'c',
+            ),
+            ClippingAudioSource(
+              child: AudioSource.uri(
+                Uri.parse("https://baz.baz/baz.mp3"),
+                tag: 'd',
+              ),
+            ),
+          ],
+        );
+    final source1 = createSource();
+    //expect(source1.shuffleIndices, [4, 0, 1, 3, 2]);
+    checkIndices(source1.shuffleIndices, 5);
+    expect(source1.shuffleIndices.skipWhile((i) => i != 0).skip(1).first,
+        equals(1));
+    final player1 = AudioPlayer();
+    await player1.load(source1);
+    checkIndices(player1.shuffleIndices, 5);
+    expect(player1.shuffleIndices.first, equals(0));
+    await player1.seek(Duration.zero, index: 3);
+    await player1.shuffle();
+    checkIndices(player1.shuffleIndices, 5);
+    expect(player1.shuffleIndices.first, equals(3));
+
+    final source2 = createSource();
+    final player2 = AudioPlayer();
+    await player2.load(source2, initialIndex: 3);
+    checkIndices(player2.shuffleIndices, 5);
+    expect(player2.shuffleIndices.first, equals(3));
+  });
 }
 
 class MockJustAudio extends Mock
@@ -543,6 +639,12 @@ class MockAudioPlayer implements AudioPlayerPlatform {
     return SetShuffleModeResponse();
   }
 
+  @override
+  Future<SetShuffleOrderResponse> setShuffleOrder(
+      SetShuffleOrderRequest request) async {
+    return SetShuffleOrderResponse();
+  }
+
   @override
   Future<SetSpeedResponse> setSpeed(SetSpeedRequest request) async {
     _speed = request.speed;

just_audio_platform_interface/lib/just_audio_platform_interface.dart

@@ -103,6 +103,12 @@ abstract class AudioPlayerPlatform {
     throw UnimplementedError("setShuffleMode() has not been implemented.");
   }
 
+  /// Sets the shuffle order.
+  Future<SetShuffleOrderResponse> setShuffleOrder(
+      SetShuffleOrderRequest request) {
+    throw UnimplementedError("setShuffleOrder() has not been implemented.");
+  }
+
   /// On iOS and macOS, sets the automaticallyWaitsToMinimizeStalling option,
   /// and does nothing on other platforms.
   Future<SetAutomaticallyWaitsToMinimizeStallingResponse>
@@ -431,6 +437,25 @@ class SetShuffleModeResponse {
 /// The shuffle mode communicated to the platform implementation.
 enum ShuffleModeMessage { none, all }
 
+/// Information communicated to the platform implementation when setting the
+/// shuffle order.
+class SetShuffleOrderRequest {
+  final AudioSourceMessage audioSourceMessage;
+
+  SetShuffleOrderRequest({@required this.audioSourceMessage});
+
+  Map<dynamic, dynamic> toMap() => {
+        'audioSource': audioSourceMessage.toMap(),
+      };
+}
+
+/// Information returned by the platform implementation after setting the
+/// shuffle order.
+class SetShuffleOrderResponse {
+  static SetShuffleOrderResponse fromMap(Map<dynamic, dynamic> map) =>
+      SetShuffleOrderResponse();
+}
+
 /// Information communicated to the platform implementation when setting the
 /// automaticallyWaitsToMinimizeStalling option.
 class SetAutomaticallyWaitsToMinimizeStallingRequest {
@@ -515,17 +540,20 @@ class ConcatenatingInsertAllRequest {
   final String id;
   final int index;
   final List<AudioSourceMessage> children;
+  final List<int> shuffleOrder;
 
   ConcatenatingInsertAllRequest({
     @required this.id,
     @required this.index,
     @required this.children,
+    @required this.shuffleOrder,
   });
 
   Map<dynamic, dynamic> toMap() => {
         'id': id,
         'index': index,
         'children': children.map((child) => child.toMap()).toList(),
+        'shuffleOrder': shuffleOrder,
       };
 }
 
@@ -542,17 +570,20 @@ class ConcatenatingRemoveRangeRequest {
   final String id;
   final int startIndex;
   final int endIndex;
+  final List<int> shuffleOrder;
 
   ConcatenatingRemoveRangeRequest({
     @required this.id,
     @required this.startIndex,
     @required this.endIndex,
+    @required this.shuffleOrder,
   });
 
   Map<dynamic, dynamic> toMap() => {
         'id': id,
         'startIndex': startIndex,
         'endIndex': endIndex,
+        'shuffleOrder': shuffleOrder,
       };
 }
 
@@ -569,17 +600,20 @@ class ConcatenatingMoveRequest {
   final String id;
   final int currentIndex;
   final int newIndex;
+  final List<int> shuffleOrder;
 
   ConcatenatingMoveRequest({
     @required this.id,
     @required this.currentIndex,
     @required this.newIndex,
+    @required this.shuffleOrder,
   });
 
   Map<dynamic, dynamic> toMap() => {
         'id': id,
         'currentIndex': currentIndex,
         'newIndex': newIndex,
+        'shuffleOrder': shuffleOrder,
       };
 }
 
@@ -678,11 +712,13 @@ class HlsAudioSourceMessage extends UriAudioSourceMessage {
 class ConcatenatingAudioSourceMessage extends AudioSourceMessage {
   final List<AudioSourceMessage> children;
   final bool useLazyPreparation;
+  final List<int> shuffleOrder;
 
   ConcatenatingAudioSourceMessage({
     @required String id,
     @required this.children,
     @required this.useLazyPreparation,
+    @required this.shuffleOrder,
   }) : super(id: id);
 
   @override
@@ -691,6 +727,7 @@ class ConcatenatingAudioSourceMessage extends AudioSourceMessage {
         'id': id,
         'children': children.map((child) => child.toMap()).toList(),
         'useLazyPreparation': useLazyPreparation,
+        'shuffleOrder': shuffleOrder,
       };
 }
 

just_audio_platform_interface/lib/method_channel_just_audio.dart

@@ -79,6 +79,13 @@ class MethodChannelAudioPlayer extends AudioPlayerPlatform {
         await _channel.invokeMethod('setShuffleMode', request?.toMap()));
   }
 
+  @override
+  Future<SetShuffleOrderResponse> setShuffleOrder(
+      SetShuffleOrderRequest request) async {
+    return SetShuffleOrderResponse.fromMap(
+        await _channel.invokeMethod('setShuffleOrder', request?.toMap()));
+  }
+
   @override
   Future<SetAutomaticallyWaitsToMinimizeStallingResponse>
       setAutomaticallyWaitsToMinimizeStalling(

just_audio_web/lib/just_audio_web.dart

@@ -112,7 +112,7 @@ class Html5AudioPlayer extends JustAudioPlayer {
     final sequence = _audioSourcePlayer.sequence;
     List<int> order = List<int>(sequence.length);
     if (_shuffleModeEnabled) {
-      order = _audioSourcePlayer.shuffleOrder;
+      order = _audioSourcePlayer.shuffleIndices;
     } else {
       for (var i = 0; i < order.length; i++) {
         order[i] = i;
@@ -181,9 +181,6 @@ class Html5AudioPlayer extends JustAudioPlayer {
     _currentAudioSourcePlayer?.pause();
     _audioSourcePlayer = getAudioSource(request.audioSourceMessage);
     _index = request.initialIndex ?? 0;
-    if (_shuffleModeEnabled) {
-      _audioSourcePlayer?.shuffle(0, _index);
-    }
     final duration = await _currentAudioSourcePlayer.load();
     if (request.initialPosition != null) {
       await _currentAudioSourcePlayer
@@ -259,12 +256,30 @@ class Html5AudioPlayer extends JustAudioPlayer {
   Future<SetShuffleModeResponse> setShuffleMode(
       SetShuffleModeRequest request) async {
     _shuffleModeEnabled = request.shuffleMode == ShuffleModeMessage.all;
-    if (_shuffleModeEnabled) {
-      _audioSourcePlayer?.shuffle(0, _index);
-    }
     return SetShuffleModeResponse();
   }
 
+  @override
+  Future<SetShuffleOrderResponse> setShuffleOrder(
+      SetShuffleOrderRequest request) async {
+    void internalSetShuffleOrder(AudioSourceMessage sourceMessage) {
+      final audioSourcePlayer = _audioSourcePlayers[sourceMessage.id];
+      if (audioSourcePlayer == null) return;
+      if (sourceMessage is ConcatenatingAudioSourceMessage &&
+          audioSourcePlayer is ConcatenatingAudioSourcePlayer) {
+        audioSourcePlayer.setShuffleOrder(sourceMessage.shuffleOrder);
+        for (var childMessage in sourceMessage.children) {
+          internalSetShuffleOrder(childMessage);
+        }
+      } else if (sourceMessage is LoopingAudioSourceMessage) {
+        internalSetShuffleOrder(sourceMessage.child);
+      }
+    }
+
+    internalSetShuffleOrder(request.audioSourceMessage);
+    return SetShuffleOrderResponse();
+  }
+
   @override
   Future<SeekResponse> seek(SeekRequest request) async {
     await _seek(request.position.inMilliseconds, request.index);
@@ -294,6 +309,7 @@ class Html5AudioPlayer extends JustAudioPlayer {
       ConcatenatingInsertAllRequest request) async {
     _concatenating(request.id)
         .insertAll(request.index, getAudioSources(request.children));
+    _concatenating(request.id).setShuffleOrder(request.shuffleOrder);
     if (request.index <= _index) {
       _index += request.children.length;
     }
@@ -309,6 +325,7 @@ class Html5AudioPlayer extends JustAudioPlayer {
     }
     _concatenating(request.id)
         .removeRange(request.startIndex, request.endIndex);
+    _concatenating(request.id).setShuffleOrder(request.shuffleOrder);
     if (_index >= request.startIndex && _index < request.endIndex) {
       // Skip backward if there's nothing after this
       if (request.startIndex >= _audioSourcePlayer.sequence.length) {
@@ -332,6 +349,7 @@ class Html5AudioPlayer extends JustAudioPlayer {
   Future<ConcatenatingMoveResponse> concatenatingMove(
       ConcatenatingMoveRequest request) async {
     _concatenating(request.id).move(request.currentIndex, request.newIndex);
+    _concatenating(request.id).setShuffleOrder(request.shuffleOrder);
     if (request.currentIndex == _index) {
       _index = request.newIndex;
     } else if (request.currentIndex < _index && request.newIndex >= _index) {
@@ -401,7 +419,8 @@ class Html5AudioPlayer extends JustAudioPlayer {
           this,
           audioSourceMessage.id,
           getAudioSources(audioSourceMessage.children),
-          audioSourceMessage.useLazyPreparation);
+          audioSourceMessage.useLazyPreparation,
+          audioSourceMessage.shuffleOrder);
     } else if (audioSourceMessage is ClippingAudioSourceMessage) {
       return ClippingAudioSourcePlayer(
           this,
@@ -426,9 +445,7 @@ abstract class AudioSourcePlayer {
 
   List<IndexedAudioSourcePlayer> get sequence;
 
-  List<int> get shuffleOrder;
+  List<int> get shuffleIndices;
-
-  int shuffle(int treeIndex, int currentIndex);
 }
 
 abstract class IndexedAudioSourcePlayer extends AudioSourcePlayer {
@@ -455,9 +472,6 @@ abstract class IndexedAudioSourcePlayer extends AudioSourcePlayer {
 
   AudioElement get _audioElement => html5AudioPlayer._audioElement;
 
-  @override
-  int shuffle(int treeIndex, int currentIndex) => treeIndex + 1;
-
   @override
   String toString() => "${this.runtimeType}";
 }
@@ -477,7 +491,7 @@ abstract class UriAudioSourcePlayer extends IndexedAudioSourcePlayer {
   List<IndexedAudioSourcePlayer> get sequence => [this];
 
   @override
-  List<int> get shuffleOrder => [0];
+  List<int> get shuffleIndices => [0];
 
   @override
   Future<Duration> load() async {
@@ -566,33 +580,13 @@ class HlsAudioSourcePlayer extends UriAudioSourcePlayer {
 }
 
 class ConcatenatingAudioSourcePlayer extends AudioSourcePlayer {
-  static List<int> generateShuffleOrder(int length, [int firstIndex]) {
-    final shuffleOrder = List<int>(length);
-    for (var i = 0; i < length; i++) {
-      final j = _random.nextInt(i + 1);
-      shuffleOrder[i] = shuffleOrder[j];
-      shuffleOrder[j] = i;
-    }
-    if (firstIndex != null) {
-      for (var i = 1; i < length; i++) {
-        if (shuffleOrder[i] == firstIndex) {
-          final v = shuffleOrder[0];
-          shuffleOrder[0] = shuffleOrder[i];
-          shuffleOrder[i] = v;
-          break;
-        }
-      }
-    }
-    return shuffleOrder;
-  }
-
   final List<AudioSourcePlayer> audioSourcePlayers;
   final bool useLazyPreparation;
   List<int> _shuffleOrder;
 
   ConcatenatingAudioSourcePlayer(Html5AudioPlayer html5AudioPlayer, String id,
-      this.audioSourcePlayers, this.useLazyPreparation)
+      this.audioSourcePlayers, this.useLazyPreparation, List<int> shuffleOrder)
-      : _shuffleOrder = generateShuffleOrder(audioSourcePlayers.length),
+      : _shuffleOrder = shuffleOrder,
         super(html5AudioPlayer, id);
 
   @override
@@ -600,14 +594,14 @@ class ConcatenatingAudioSourcePlayer extends AudioSourcePlayer {
       audioSourcePlayers.expand((p) => p.sequence).toList();
 
   @override
-  List<int> get shuffleOrder {
+  List<int> get shuffleIndices {
     final order = <int>[];
     var offset = order.length;
     final childOrders = <List<int>>[];
     for (var audioSourcePlayer in audioSourcePlayers) {
-      final childShuffleOrder = audioSourcePlayer.shuffleOrder;
+      final childShuffleIndices = audioSourcePlayer.shuffleIndices;
-      childOrders.add(childShuffleOrder.map((i) => i + offset).toList());
+      childOrders.add(childShuffleIndices.map((i) => i + offset).toList());
-      offset += childShuffleOrder.length;
+      offset += childShuffleIndices.length;
     }
     for (var i = 0; i < childOrders.length; i++) {
       order.addAll(childOrders[_shuffleOrder[i]]);
@@ -615,21 +609,8 @@ class ConcatenatingAudioSourcePlayer extends AudioSourcePlayer {
     return order;
   }
 
-  @override
+  void setShuffleOrder(List<int> shuffleOrder) {
-  int shuffle(int treeIndex, int currentIndex) {
+    _shuffleOrder = shuffleOrder;
-    int currentChildIndex;
-    for (var i = 0; i < audioSourcePlayers.length; i++) {
-      final indexBefore = treeIndex;
-      final child = audioSourcePlayers[i];
-      treeIndex = child.shuffle(treeIndex, currentIndex);
-      if (currentIndex >= indexBefore && currentIndex < treeIndex) {
-        currentChildIndex = i;
-      } else {}
-    }
-    // Shuffle so that the current child is first in the shuffle order
-    _shuffleOrder =
-        generateShuffleOrder(audioSourcePlayers.length, currentChildIndex);
-    return treeIndex;
   }
 
   insertAll(int index, List<AudioSourcePlayer> players) {
@@ -639,8 +620,6 @@ class ConcatenatingAudioSourcePlayer extends AudioSourcePlayer {
         _shuffleOrder[i] += players.length;
       }
     }
-    _shuffleOrder.addAll(
-        List.generate(players.length, (i) => index + i).toList()..shuffle());
   }
 
   removeRange(int start, int end) {
@@ -650,7 +629,6 @@ class ConcatenatingAudioSourcePlayer extends AudioSourcePlayer {
         _shuffleOrder[i] -= (end - start);
       }
     }
-    _shuffleOrder.removeWhere((i) => i >= start && i < end);
   }
 
   move(int currentIndex, int newIndex) {
@@ -675,7 +653,7 @@ class ClippingAudioSourcePlayer extends IndexedAudioSourcePlayer {
   List<IndexedAudioSourcePlayer> get sequence => [this];
 
   @override
-  List<int> get shuffleOrder => [0];
+  List<int> get shuffleIndices => [0];
 
   @override
   Future<Duration> load() async {
@@ -799,22 +777,14 @@ class LoopingAudioSourcePlayer extends AudioSourcePlayer {
           .toList();
 
   @override
-  List<int> get shuffleOrder {
+  List<int> get shuffleIndices {
     final order = <int>[];
     var offset = order.length;
     for (var i = 0; i < count; i++) {
-      final childShuffleOrder = audioSourcePlayer.shuffleOrder;
+      final childShuffleOrder = audioSourcePlayer.shuffleIndices;
       order.addAll(childShuffleOrder.map((i) => i + offset).toList());
       offset += childShuffleOrder.length;
     }
     return order;
   }
-
-  @override
-  int shuffle(int treeIndex, int currentIndex) {
-    for (var i = 0; i < count; i++) {
-      treeIndex = audioSourcePlayer.shuffle(treeIndex, currentIndex);
-    }
-    return treeIndex;
-  }
 }

just_audio_web/pubspec.lock

@@ -28,9 +28,9 @@ packages:
   just_audio_platform_interface:
     dependency: "direct main"
     description:
-      name: just_audio_platform_interface
+      path: "../just_audio_platform_interface"
-      url: "https://pub.dartlang.org"
+      relative: true
-    source: hosted
+    source: path
     version: "1.1.1"
   meta:
     dependency: "direct main"

just_audio_web/pubspec.yaml

@@ -11,7 +11,10 @@ flutter:
         fileName: just_audio_web.dart
 
 dependencies:
-  just_audio_platform_interface: ^1.1.1
+  # TODO: change this back when the new platform interface is published.
+  # just_audio_platform_interface: ^1.1.1
+  just_audio_platform_interface:
+    path: ../just_audio_platform_interface
   flutter:
     sdk: flutter
   flutter_web_plugins: