GLSpectrum: synchronize spectrum running with the GUI spectrum freeze button. Fixes issue #561

sdrbase/dsp/spectrumvis.cpp

@@ -626,12 +626,24 @@ void SpectrumVis::feed(const SampleVector::const_iterator& cbegin, const SampleV
 
 void SpectrumVis::start()
 {
-    m_running = true;
+    setRunning(true);
+
+    if (getMessageQueueToGUI()) // propagate to GUI if any
+    {
+        MsgStartStop *msg = MsgStartStop::create(true);
+        getMessageQueueToGUI()->push(msg);
+    }
 }
 
 void SpectrumVis::stop()
 {
-    m_running = false;
+    setRunning(false);
+
+    if (getMessageQueueToGUI()) // propagate to GUI if any
+    {
+        MsgStartStop *msg = MsgStartStop::create(false);
+        getMessageQueueToGUI()->push(msg);
+    }
 }
 
 bool SpectrumVis::handleMessage(const Message& message)
@@ -670,14 +682,10 @@ bool SpectrumVis::handleMessage(const Message& message)
         handleConfigureWSSpectrum(conf.getAddress(), conf.getPort());
         return true;
     }
-    else if (MsgStartStop::match(message)) {
+    else if (MsgStartStop::match(message))
+    {
         MsgStartStop& cmd = (MsgStartStop&) message;
-
-        if (cmd.getStartStop()) {
-            start();
-        } else {
-            stop();
-        }
+        setRunning(cmd.getStartStop());
 
         return true;
     }

sdrbase/dsp/spectrumvis.h

@@ -199,6 +199,7 @@ private:
 
 	QMutex m_mutex;
 
+    void setRunning(bool running) { m_running = running; }
     void applySettings(const GLSpectrumSettings& settings, bool force = false);
     void handleConfigureDSP(uint64_t centerFrequency, int sampleRate);
     void handleScalef(Real scalef);

sdrgui/gui/glspectrumgui.cpp

@@ -492,6 +492,14 @@ bool GLSpectrumGUI::handleMessage(const Message& message)
         setAveragingToolitp();
         return true;
     }
+    else if (SpectrumVis::MsgStartStop::match(message))
+    {
+        const SpectrumVis::MsgStartStop& msg = (SpectrumVis::MsgStartStop&) message;
+        ui->freeze->blockSignals(true);
+        ui->freeze->doToggle(!msg.getStartStop()); // this is a freeze so stop is true
+        ui->freeze->blockSignals(false);
+        return true;
+    }
 
     return false;
 }