Add listener support to Controller for device change notifications

Author: mfisher31

src/controller.cpp

@@ -22,6 +22,7 @@ struct Controller::Impl : public MidiKeyboardStateListener {
     juce::String virtualDeviceName { "VMC-MIDI-Out" };
     Device device;
     juce::File deviceFile;
+    ListenerList<Controller::Listener> listeners;
 
     void saveSettings()
     {
@@ -53,6 +54,7 @@ struct Controller::Impl : public MidiKeyboardStateListener {
     {
         if (device.load (file)) {
             deviceFile = file;
+            listeners.call (&Controller::Listener::deviceChanged);
             return true;
         }
         return false;
@@ -180,4 +182,7 @@ void Controller::audioDeviceAboutToStart (AudioIODevice*) {}
 void Controller::audioDeviceStopped() {}
 void Controller::audioDeviceError (const String& errorMessage) { juce::ignoreUnused (errorMessage); }
 
+void Controller::addListener (Listener* listener) { impl->listeners.add (listener); }
+void Controller::removeListener (Listener* listener) { impl->listeners.remove (listener); }
+
 } // namespace vmc

src/controller.hpp

@@ -17,6 +17,11 @@ class Controller final : public AudioIODeviceCallback,
 public:
     Controller();
     ~Controller();
+    
+    struct Listener {
+        virtual ~Listener() = default;
+        virtual void deviceChanged() = 0;
+    };
 
     Device device() const;
     bool loadDeviceFile (const juce::File&);
@@ -53,7 +58,10 @@ class Controller final : public AudioIODeviceCallback,
     virtual void handleIncomingMidiMessage (MidiInput*, const MidiMessage&) override {}
     virtual void handlePartialSysexMessage (MidiInput*, const uint8*,
                                             int, double) override {}
-
+    
+    void addListener (Listener*);
+    void removeListener (Listener*);
+    
 private:
     struct Impl;
     std::unique_ptr<Impl> impl;

src/main.cpp

@@ -57,13 +57,15 @@ class Application : public JUCEApplication {
         ignoreUnused (commandLine);
     }
 
-    class MainWindow : public DocumentWindow {
+    class MainWindow : public DocumentWindow,
+                        public Controller::Listener {
     public:
         MainWindow (String name, Controller& vc)
             : DocumentWindow (name, Desktop::getInstance().getDefaultLookAndFeel().findColour (ResizableWindow::backgroundColourId),
                               DocumentWindow::closeButton | DocumentWindow::minimiseButton),
               controller (vc)
         {
+            controller.addListener (this);
 #if JUCE_LINUX
             setUsingNativeTitleBar (false);
 #else
@@ -81,11 +83,14 @@ class Application : public JUCEApplication {
             setContentComponentSize (VMC_WIDTH, VMC_HEIGHT);
             setResizable (false, false);
 
+            deviceChanged();
+            
             setVisible (true);
         }
 
         ~MainWindow() override
         {
+            controller.removeListener (this);
             clearContentComponent();
             setConstrainer (nullptr);
         }
@@ -110,6 +115,12 @@ class Application : public JUCEApplication {
             return;
         }
 
+        void deviceChanged() override
+        {
+            auto name = controller.deviceFile().getFileNameWithoutExtension();
+            setName ("Virtual MIDI Controller - " + name);
+        }
+
     private:
         Controller& controller;
         ComponentBoundsConstrainer constrain;