Remember settings when toggling modem types

- Some additional race condition fixes for showing/hiding the modem
property grid

src/AppFrame.cpp

@@ -950,6 +950,8 @@ void AppFrame::OnIdle(wxIdleEvent& event) {
             demodGainMeter->setLevel(demodGainMeter->getInputValue());
         }
         activeDemodulator = demod;
+    } else if (demod) {
+        // Wait state for current demodulator modem to activate..
     } else {
         DemodulatorMgr *mgr = &wxGetApp().getDemodMgr();
 

src/demod/DemodulatorInstance.cpp

@@ -240,6 +240,10 @@ int DemodulatorInstance::getOutputDevice() {
 void DemodulatorInstance::setDemodulatorType(std::string demod_type_in) {
     setGain(getGain());
     if (demodulatorPreThread) {
+        std::string currentDemodType = demodulatorPreThread->getDemodType();
+        if ((currentDemodType != "") && (currentDemodType != demod_type_in)) {
+            lastModemSettings[currentDemodType] = demodulatorPreThread->readModemSettings();
+        }
         demodulatorPreThread->setDemodType(demod_type_in);
     }
 }
@@ -366,4 +370,13 @@ void DemodulatorInstance::writeModemSettings(ModemSettings settings) {
 
 bool DemodulatorInstance::isModemInitialized() {
     return demodulatorPreThread->isInitialized();
-}
+}
+
+ModemSettings DemodulatorInstance::getLastModemSettings(std::string demodType) {
+    if (lastModemSettings.find(demodType) != lastModemSettings.end()) {
+        return lastModemSettings[demodType];
+    } else {
+        ModemSettings mods;
+        return mods;
+    }
+}

src/demod/DemodulatorInstance.h

@@ -89,7 +89,8 @@ public:
     void writeModemSettings(ModemSettings settings);
     
     bool isModemInitialized();
-
+    ModemSettings getLastModemSettings(std::string demodType);
+    
 protected:
     DemodulatorThreadInputQueue* pipeIQInputData;
     DemodulatorThreadPostInputQueue* pipeIQDemodData;
@@ -113,4 +114,5 @@ private:
     std::atomic_int currentOutputDevice;
     std::atomic<float> currentAudioGain;
     std::atomic_bool follow, tracking;
+    std::map<std::string, ModemSettings> lastModemSettings;
   };

src/demod/DemodulatorPreThread.cpp

@@ -103,7 +103,15 @@ void DemodulatorPreThread::run() {
             demodType = newDemodType;
             sampleRateChanged.store(false);
             audioSampleRateChanged.store(false);
-            if (modemSettingsBuffered.size()) {
+            ModemSettings lastSettings = parent->getLastModemSettings(newDemodType);
+            if (lastSettings.size() != 0) {
+                command.settings = lastSettings;
+                if (modemSettingsBuffered.size()) {
+                    for (ModemSettings::const_iterator msi = modemSettingsBuffered.begin(); msi != modemSettingsBuffered.end(); msi++) {
+                        command.settings[msi->first] = msi->second;
+                    }
+                }
+            } else {
                 command.settings = modemSettingsBuffered;
             }
             modemSettingsBuffered.clear();