fix: Resolve enable state for v4l and screen capture (#728)

* fix: Resolve the enable state for v4l and screen capture

* Use instance index instead of pointer

* Second try

* fix(QtGrabber): QScreen ownership

* Remove v4l2 compState listener

include/grabber/V4L2Grabber.h

@@ -90,8 +90,6 @@ public slots:
 
 	void stop();
 
-	void compStateChangeRequest(const hyperion::Components component, bool enable);
-
 signals:
 	void newFrame(const Image<ColorRgb> & image);
 	void readError(const char* err);

include/grabber/V4L2Wrapper.h

@@ -27,7 +27,6 @@ public slots:
 	void setDeviceVideoStandard(QString device, VideoStandard videoStandard);
 
 signals:
-	void compStateChangeRequest(const hyperion::Components component, bool enable);
 
 private slots:
 	void newFrame(const Image<ColorRgb> & image);

include/hyperion/Grabber.h

@@ -97,12 +97,6 @@ public:
 	///
 	void setEnabled(bool enable);
 
-signals:
-	///
-	/// @brief PIPE component state changes from HyperionDaemon to V4L2Grabber
-	///
-	void compStateChangeRequest(const hyperion::Components component, bool enable);
-
 protected:
 	ImageResampler _imageResampler;
 

include/hyperion/GrabberWrapper.h

@@ -17,6 +17,10 @@ class Grabber;
 class GlobalSignals;
 class QTimer;
 
+/// List of Hyperion instances that requested screen capt
+static QList<int> GRABBER_SYS_CLIENTS;
+static QList<int> GRABBER_V4L_CLIENTS;
+
 ///
 /// This class will be inherted by FramebufferWrapper and others which contains the real capture interface
 ///
@@ -33,6 +37,11 @@ public:
 	///
 	virtual bool start();
 
+	///
+	/// Starts maybe the grabber wich produces led values with the specified update rate
+	///
+	virtual void tryStart();
+
 	///
 	/// Stop grabber
 	///
@@ -94,8 +103,12 @@ signals:
 	///
 	void systemImage(const QString& name, const Image<ColorRgb>& image);
 
-protected:
+private slots:
+	/// @brief Handle a source request event from Hyperion.
+	/// Will start and stop grabber based on active listeners count
+	void handleSourceRequest(const hyperion::Components& component, const int hyperionInd, const bool listen);
 
+protected:
 	QString _grabberName;
 
 	/// The timer for generating events with the specified update rate

include/utils/GlobalSignals.h

@@ -92,4 +92,12 @@ signals:
 	///
 	void globalRegRequired(int priority);
 
+	///
+	/// @brief Tell v4l2/screen capture the listener state
+	/// @param component  The component to handle
+	/// @param hyperionInd The Hyperion instance index as identifier
+	/// @param listen  True when listening, else false
+	///
+	void requestSource(const hyperion::Components& component, const int hyperionInd, const bool listen);
+
 };