media player: finish incomplete implementation

Sources/VLCMediaPlayer.m

@@ -169,7 +169,7 @@ static void HandleMediaTitleChanged(const libvlc_event_t * event, void * self)
 {
     @autoreleasepool {
         [[VLCEventManager sharedManager] callOnMainThreadDelegateOfObject:(__bridge id)(self)
-                                                       withDelegateMethod:@selector(mediaPlayerTimeChanged:)
+                                                       withDelegateMethod:@selector(mediaPlayerTitleChanged:)
                                                      withNotificationName:VLCMediaPlayerTitleChanged];
     }
 }
@@ -1374,6 +1374,18 @@ static void HandleMediaPlayerSnapshot(const libvlc_event_t * event, void * self)
     [self didChangeValueForKey:@"media"];
 }
 
+- (void)mediaPlayerTitleChanged:(NSNumber *)newTitle
+{
+    [self willChangeValueForKey:@"currentTitleIndex"];
+    [self didChangeValueForKey:@"currentTitleIndex"];
+}
+
+- (void)mediaPlayerChapterChanged:(NSNumber *)newChapter
+{
+    [self willChangeValueForKey:@"currentChapterIndex"];
+    [self didChangeValueForKey:@"currentChapterIndex"];
+}
+
 #if TARGET_OS_IPHONE
 - (void)mediaPlayerSnapshot:(NSString *)fileName
 {