desklink: use media_server notifications instead of polling.

* This removes Pulse(), which would constantly reconnect to
  the mixer. With the previous changes to the
  DefaultMediaTheme, this also makes changes to the muted
  state instaneous when modified by some other app.

src/bin/desklink/MediaReplicant.cpp

@@ -131,7 +131,6 @@ public:
 	virtual void			MouseDown(BPoint point);
 	virtual void			Draw(BRect updateRect);
 	virtual void			MessageReceived(BMessage* message);
-	virtual void			Pulse();
 
 private:
 			status_t		_LaunchByPath(const char* path);
@@ -143,6 +142,11 @@ private:
 			void			_SaveSettings();
 			void			_Init();
 
+			void			_DisconnectMixer();
+			status_t		_ConnectMixer();
+
+			MixerControl*	fMixerControl;
+
 			BBitmap*		fIcon;
 			BBitmap*		fMutedIcon;
 			VolumeWindow*	fVolumeSlider;
@@ -179,6 +183,7 @@ MediaReplicant::~MediaReplicant()
 {
 	delete fIcon;
 	_SaveSettings();
+	_DisconnectMixer();
 }
 
 
@@ -208,6 +213,8 @@ MediaReplicant::AttachedToWindow()
 {
 	AdoptParentColors();
 
+	_ConnectMixer();
+
 	BView::AttachedToWindow();
 }
 
@@ -267,13 +274,13 @@ MediaReplicant::MouseDown(BPoint point)
 			where + BPoint(4, 4)));
 
 	} else if ((buttons & B_TERTIARY_MOUSE_BUTTON) != 0) {
-		MixerControl mixerControl;
-		if (mixerControl.Connect(fVolumeWhich)) {
-			mixerControl.SetMute(!fMuted);
-			fMuted = mixerControl.Mute();
+		if (fMixerControl != NULL) {
+			fMixerControl->SetMute(!fMuted);
+			fMuted = fMixerControl->Mute();
 			VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip());
 			if (tip != NULL) {
 				tip->SetMuteMessage(fMuted ? B_TRANSLATE("Muted"): NULL);
+				tip->Update();
 				ShowToolTip(tip);
 			}
 			Invalidate();
@@ -288,28 +295,6 @@ MediaReplicant::MouseDown(BPoint point)
 }
 
 
-void
-MediaReplicant::Pulse()
-{
-	bool setMuted = false;
-	MixerControl mixerControl;
-	const char* errorString = NULL;
-	if (!mixerControl.Connect(fVolumeWhich, NULL, &errorString)) {
-		fMuted = true;
-		errorString = NULL;
-	} else
-		setMuted = mixerControl.Mute();
-
-	if (setMuted != fMuted) {
-		fMuted = setMuted;
-		VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip());
-		if (tip != NULL)
-			tip->SetMuteMessage(errorString);
-		Invalidate();
-	}
-}
-
-
 void
 MediaReplicant::MessageReceived(BMessage* message)
 {
@@ -350,8 +335,18 @@ MediaReplicant::MessageReceived(BMessage* message)
 			fVolumeWhich = item->IsMarked()
 				? VOLUME_USE_PHYS_OUTPUT : VOLUME_USE_MIXER;
 
-			if (VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip()))
+			if (_ConnectMixer() != B_OK
+				&& fVolumeWhich == VOLUME_USE_PHYS_OUTPUT) {
+				// unable to switch to physical output
+				item->SetMarked(false);
+				fVolumeWhich = VOLUME_USE_MIXER;
+				_ConnectMixer();
+			}
+
+			if (VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip())) {
 				tip->SetWhich(fVolumeWhich);
+				tip->Update();
+			}
 			break;
 		}
 
@@ -359,10 +354,8 @@ MediaReplicant::MessageReceived(BMessage* message)
 		{
 			float deltaY;
 			if (message->FindFloat("be:wheel_delta_y", &deltaY) == B_OK
-				&& deltaY != 0.0) {
-				MixerControl mixerControl;
-				mixerControl.Connect(fVolumeWhich);
-				mixerControl.ChangeVolumeBy(deltaY < 0 ? 6 : -6);
+				&& deltaY != 0.0 && fMixerControl != NULL) {
+				fMixerControl->ChangeVolumeBy(deltaY < 0 ? 6 : -6);
 
 				VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip());
 				if (tip != NULL) {
@@ -373,6 +366,46 @@ MediaReplicant::MessageReceived(BMessage* message)
 			break;
 		}
 
+		case B_MEDIA_NEW_PARAMETER_VALUE:
+		{
+			if (fMixerControl != NULL && !fMixerControl->Connected())
+				return;
+
+			bool setMuted = fMixerControl->Mute();
+			if (setMuted != fMuted) {
+				fMuted = setMuted;
+				VolumeToolTip* tip = dynamic_cast<VolumeToolTip*>(ToolTip());
+				if (tip != NULL) {
+					tip->SetMuteMessage(fMuted ? B_TRANSLATE("Muted") : NULL);
+					tip->Update();
+				}
+				Invalidate();
+			}
+			break;
+		}
+
+		case B_MEDIA_SERVER_STARTED:
+			_ConnectMixer();
+			break;
+
+		case B_MEDIA_NODE_CREATED:
+		{
+			// It's not enough to wait for B_MEDIA_SERVER_STARTED message, as
+			// the mixer will still be getting loaded by the media server
+			media_node mixerNode;
+			media_node_id mixerNodeID;
+			BMediaRoster* roster = BMediaRoster::CurrentRoster();
+			if (roster != NULL
+				&& message->FindInt32("media_node_id",&mixerNodeID) == B_OK
+				&& roster->GetNodeFor(mixerNodeID, &mixerNode) == B_OK) {
+				if (mixerNode.kind == B_SYSTEM_MIXER) {
+					_ConnectMixer();
+					roster->ReleaseNode(mixerNode);
+				}
+			}
+			break;
+		}
+
 		default:
 			BView::MessageReceived(message);
 			break;
@@ -509,6 +542,56 @@ MediaReplicant::_Init()
 }
 
 
+void
+MediaReplicant::_DisconnectMixer()
+{
+	BMediaRoster* roster = BMediaRoster::CurrentRoster();
+	if (roster == NULL)
+		return;
+
+	roster->StopWatching(this, B_MEDIA_SERVER_STARTED | B_MEDIA_NODE_CREATED);
+
+	if (fMixerControl->MuteNode() != media_node::null) {
+		roster->StopWatching(this, fMixerControl->MuteNode(),
+			B_MEDIA_NEW_PARAMETER_VALUE);
+	}
+
+	delete fMixerControl;
+	fMixerControl = NULL;
+}
+
+
+status_t
+MediaReplicant::_ConnectMixer()
+{
+	_DisconnectMixer();
+
+	BMediaRoster* roster = BMediaRoster::Roster();
+	if (roster == NULL)
+		return B_ERROR;
+
+	roster->StartWatching(this, B_MEDIA_SERVER_STARTED | B_MEDIA_NODE_CREATED);
+
+	fMixerControl = new MixerControl(fVolumeWhich);
+
+	const char* errorString = NULL;
+	float volume = 0.0;
+	fMixerControl->Connect(fVolumeWhich, &volume, &errorString);
+
+	if (errorString != NULL) {
+		SetToolTip(errorString);
+		return B_ERROR;
+	}
+
+	if (fMixerControl->MuteNode() != media_node::null) {
+		roster->StartWatching(this, fMixerControl->MuteNode(),
+			B_MEDIA_NEW_PARAMETER_VALUE);
+	}
+
+	return B_OK;
+}
+
+
 //	#pragma mark -
 
 

src/bin/desklink/MixerControl.cpp

@@ -23,6 +23,7 @@ MixerControl::MixerControl(int32 volumeWhich)
 	:
 	fVolumeWhich(volumeWhich),
 	fGainMediaNode(media_node::null),
+	fMuteMediaNode(media_node::null),
 	fParameterWeb(NULL),
 	fMixerParameter(NULL),
 	fMuteParameter(NULL),
@@ -74,8 +75,10 @@ MixerControl::Connect(int32 volumeWhich, float* _value, const char** _error)
 					p = fParameterWeb->ParameterAt(i);
 
 					// assume the mute preceeding master gain control
-					if (!strcmp(p->Kind(), B_MUTE))
+					if (!strcmp(p->Kind(), B_MUTE)) {
 						fMuteParameter = p;
+						fMuteMediaNode = fMuteParameter->Web()->Node();
+					}
 
 					PRINT(("BParameter[%i]: %s\n", i, p->Name()));
 					if (volumeWhich == VOLUME_USE_MIXER) {
@@ -151,8 +154,10 @@ MixerControl::Connect(int32 volumeWhich, float* _value, const char** _error)
 	} else
 		errorString = "Media services not running";
 
-	if (status != B_OK)
+	if (status != B_OK) {
 		fGainMediaNode = media_node::null;
+		fMuteMediaNode = media_node::null;
+	}
 
 	if (errorString) {
 		fprintf(stderr, "MixerControl: %s.\n", errorString);

src/bin/desklink/MixerControl.h

@@ -44,12 +44,14 @@ public:
 			float			Maximum() const { return fMax; }
 
 			media_node		GainNode() { return fGainMediaNode; }
+			media_node		MuteNode() { return fMuteMediaNode; }
 
 private:
 			void			_Disconnect();
 
 			int32			fVolumeWhich;
 			media_node		fGainMediaNode;
+			media_node		fMuteMediaNode;
 			BParameterWeb*	fParameterWeb;
 			BContinuousParameter* fMixerParameter;
 			BParameter*		fMuteParameter;