CoreAudio: detection of disabled devices. Avoided some internal exceptions in the demo.

extras/JuceDemo/Source/demos/OpenGLDemo.cpp

@@ -39,25 +39,25 @@ public:
         infoLabel.setText ("These sliders demonstrate how components can be added as children "
                            "of an OpenGLComponent, in which case, their content will be rendered into "
                            "an OpenGL framebuffer and efficiently overlaid onto your GL content.", false);
-        infoLabel.setBounds ("parent.width * 0.05, bottom - 150, parent.width * 0.4, parent.height - 60");
         infoLabel.setInterceptsMouseClicks (false, false);
         addAndMakeVisible (&infoLabel);
+        infoLabel.setBounds ("parent.width * 0.05, bottom - 150, parent.width * 0.4, parent.height - 60");
 
         speedSlider.setRange (-10.0, 10.0, 0.1);
         speedSlider.setPopupMenuEnabled (true);
         speedSlider.setValue (Random::getSystemRandom().nextDouble() * 3.0, false, false);
         speedSlider.setSliderStyle (Slider::LinearHorizontal);
         speedSlider.setTextBoxStyle (Slider::TextBoxLeft, false, 80, 20);
-        speedSlider.setBounds ("parent.width * 0.05, parent.height - 65, parent.width * 0.6, top + 24");
         addAndMakeVisible (&speedSlider);
+        speedSlider.setBounds ("parent.width * 0.05, parent.height - 65, parent.width * 0.6, top + 24");
 
         sizeSlider.setRange (0.2, 2.0, 0.01);
         sizeSlider.setPopupMenuEnabled (true);
         sizeSlider.setValue (Random::getSystemRandom().nextDouble() + 0.5, false, false);
         sizeSlider.setSliderStyle (Slider::LinearHorizontal);
         sizeSlider.setTextBoxStyle (Slider::TextBoxLeft, false, 80, 20);
-        sizeSlider.setBounds ("parent.width * 0.05, parent.height - 35, parent.width * 0.6, top + 24");
         addAndMakeVisible (&sizeSlider);
+        sizeSlider.setBounds ("parent.width * 0.05, parent.height - 35, parent.width * 0.6, top + 24");
 
         startTimer (1000 / 30);
     }

modules/juce_audio_devices/native/juce_mac_CoreAudio.cpp

@@ -177,20 +177,25 @@ public:
 
         const ScopedLock sl (callbackLock);
 
-        Float64 sr;
-        UInt32 size = sizeof (Float64);
-
         AudioObjectPropertyAddress pa;
-        pa.mSelector = kAudioDevicePropertyNominalSampleRate;
         pa.mScope = kAudioObjectPropertyScopeWildcard;
         pa.mElement = kAudioObjectPropertyElementMaster;
 
+        UInt32 isAlive;
+        UInt32 size = sizeof (isAlive);
+        pa.mSelector = kAudioDevicePropertyDeviceIsAlive;
+        if (OK (AudioObjectGetPropertyData (deviceID, &pa, 0, 0, &size, &isAlive))
+             && isAlive == 0)
+            return;
+
+        Float64 sr;
+        size = sizeof (sr);
+        pa.mSelector = kAudioDevicePropertyNominalSampleRate;
         if (OK (AudioObjectGetPropertyData (deviceID, &pa, 0, 0, &size, &sr)))
             sampleRate = sr;
 
         UInt32 framesPerBuf;
         size = sizeof (framesPerBuf);
-
         pa.mSelector = kAudioDevicePropertyBufferFrameSize;
         if (OK (AudioObjectGetPropertyData (deviceID, &pa, 0, 0, &size, &framesPerBuf)))
         {