discoverer: add explicit code to start/stop the service without destroying the object

Headers/Public/VLCMediaDiscoverer.h

@@ -76,10 +76,22 @@
  * Initializes new object with specified name.
  * \param aServiceName Name of the service for this VLCMediaDiscoverer object.
  * \returns Newly created media discoverer.
+ * \note with VLCKit 3.0 and above, you need to start the discoverer explicitly after creation
  */
 - (instancetype)initWithName:(NSString *)aServiceName;
 
 /**
+ * start media discovery
+ * \returns -1 if start failed, otherwise 0
+ */
+- (int)startDiscoverer;
+
+/**
+ * stop media discovery
+ */
+- (void)stopDiscoverer;
+
+/**
  * a read-only property to retrieve the list of discovered media items
  */
 @property (weak, readonly) VLCMediaList *discoveredMedia;

Sources/VLCMediaDiscoverer.m

@@ -111,21 +111,15 @@ static void HandleMediaDiscovererEnded( const libvlc_event_t *event, void *user_
         libvlc_event_manager_t * p_em = libvlc_media_discoverer_event_manager(_mdis);
         libvlc_event_attach(p_em, libvlc_MediaDiscovererStarted, HandleMediaDiscovererStarted, (__bridge void *)(self));
         libvlc_event_attach(p_em, libvlc_MediaDiscovererEnded,   HandleMediaDiscovererEnded,   (__bridge void *)(self));
-
-        //FIXME: add more events
-        int returnValue = libvlc_media_discoverer_start(_mdis);
-        if (returnValue == -1) {
-            VKLog(@"media discovery start failed");
-            return NULL;
-        }
-
-        _running = libvlc_media_discoverer_is_running(_mdis);
     }
     return self;
 }
 
 - (void)dealloc
 {
+    if (_running)
+        [self stopDiscoverer];
+
     libvlc_event_manager_t *em = libvlc_media_list_event_manager(_mdis);
     libvlc_event_detach(em, libvlc_MediaDiscovererStarted, HandleMediaDiscovererStarted, (__bridge void *)(self));
     libvlc_event_detach(em, libvlc_MediaDiscovererEnded,   HandleMediaDiscovererEnded,   (__bridge void *)(self));
@@ -136,6 +130,23 @@ static void HandleMediaDiscovererEnded( const libvlc_event_t *event, void *user_
     libvlc_release(_privateLibrary.instance);
 }
 
+- (int)startDiscoverer
+{
+    int returnValue = libvlc_media_discoverer_start(_mdis);
+    if (returnValue == -1)
+        VKLog(@"media discovery start failed");
+
+    _running = libvlc_media_discoverer_is_running(_mdis);
+
+    return returnValue;
+}
+
+- (void)stopDiscoverer
+{
+    libvlc_media_discoverer_stop(_mdis);
+    _running = libvlc_media_discoverer_is_running(_mdis);
+}
+
 - (VLCMediaList *)discoveredMedia
 {
     if (_discoveredMedia)