From 621cb3242b44ee843aa4795adc7ec29a89293603 Mon Sep 17 00:00:00 2001
From: ad <daniel.apatin@gmail.com>
Date: Fri, 13 Apr 2018 21:27:59 +0300
Subject: [PATCH 1/2] + listener for changes of sytem volume known bug: sound
 not mutes at value 0.0

---
 MTMR/VolumeViewController.swift | 43 ++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/MTMR/VolumeViewController.swift b/MTMR/VolumeViewController.swift
index 73517f1..ee13dad 100644
--- a/MTMR/VolumeViewController.swift
+++ b/MTMR/VolumeViewController.swift
@@ -16,6 +16,39 @@ class VolumeViewController: NSCustomTouchBarItem {
         }
 
         self.view = sliderItem
+        
+        var forPropertyAddress = AudioObjectPropertyAddress(
+            mSelector: kAudioHardwareServiceDeviceProperty_VirtualMasterVolume,
+            mScope: kAudioDevicePropertyScopeOutput,
+            mElement: kAudioObjectPropertyElementMaster)
+        
+        addListenerBlock(listenerBlock: audioObjectPropertyListenerBlock,
+                         onAudioObjectID: defaultDeviceID,
+                         forPropertyAddress: &forPropertyAddress)
+    }
+    
+    func addListenerBlock( listenerBlock: @escaping AudioObjectPropertyListenerBlock, onAudioObjectID: AudioObjectID, forPropertyAddress: UnsafePointer<AudioObjectPropertyAddress>) {
+
+        if (kAudioHardwareNoError != AudioObjectAddPropertyListenerBlock(onAudioObjectID, forPropertyAddress, nil, listenerBlock)) {
+            print("Error calling: AudioObjectAddPropertyListenerBlock") }
+    }
+    
+    func audioObjectPropertyListenerBlock (numberAddresses: UInt32, addresses: UnsafePointer<AudioObjectPropertyAddress>) {
+        var index: UInt32 = 0
+        while index < numberAddresses {
+            let address: AudioObjectPropertyAddress = addresses[Int(index)]
+            switch address.mSelector {
+            case kAudioHardwareServiceDeviceProperty_VirtualMasterVolume:
+                DispatchQueue.main.async {
+                    self.sliderItem.floatValue = self.getInputGain() * 100
+                }
+            default:
+                
+                print("We didn't expect this!")
+                
+            }
+            index += 1
+        }
     }
     
     required init?(coder: NSCoder) {
@@ -24,7 +57,7 @@ class VolumeViewController: NSCustomTouchBarItem {
     
     @objc func sliderValueChanged(_ sender: Any) {
         if let sliderItem = sender as? NSSlider {
-            setInputGain(Float32(sliderItem.intValue)/100.0)
+            _ = setInputGain(Float32(sliderItem.intValue)/100.0)
         }
     }
     
@@ -51,10 +84,14 @@ class VolumeViewController: NSCustomTouchBarItem {
     }
     
     private func setInputGain(_ volume: Float32) -> OSStatus {
-        var inputVolume: Float32 = volume
+        var inputVolume: Float32 = volume //0.0 //roundf(volume * 100) / 100
         let size: UInt32 = UInt32(MemoryLayout.size(ofValue: inputVolume))
         var address: AudioObjectPropertyAddress = AudioObjectPropertyAddress()
-        address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
+        if inputVolume == 0.0 {
+            address.mSelector = AudioObjectPropertySelector(kAudioDevicePropertyMute)
+        } else {
+            address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
+        }
         address.mScope = AudioObjectPropertyScope(kAudioDevicePropertyScopeOutput)
         address.mElement = AudioObjectPropertyElement(kAudioObjectPropertyElementMaster)
         return AudioObjectSetPropertyData(defaultDeviceID, &address, 0, nil, size, &inputVolume)

From 849b5b6db0c61bef902e87c32c448c9fbcfc45a3 Mon Sep 17 00:00:00 2001
From: ad <daniel.apatin@gmail.com>
Date: Fri, 13 Apr 2018 21:40:34 +0300
Subject: [PATCH 2/2] * fixed bug with mute at 0.0

---
 MTMR/VolumeViewController.swift | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/MTMR/VolumeViewController.swift b/MTMR/VolumeViewController.swift
index ee13dad..b73aeb7 100644
--- a/MTMR/VolumeViewController.swift
+++ b/MTMR/VolumeViewController.swift
@@ -84,18 +84,31 @@ class VolumeViewController: NSCustomTouchBarItem {
     }
     
     private func setInputGain(_ volume: Float32) -> OSStatus {
-        var inputVolume: Float32 = volume //0.0 //roundf(volume * 100) / 100
+        var inputVolume: Float32 = volume
+        
+        if inputVolume == 0.0 {
+           _ = setMute( mute: 1)
+        } else {
+            _ = setMute( mute: 0)
+        }
+        
         let size: UInt32 = UInt32(MemoryLayout.size(ofValue: inputVolume))
         var address: AudioObjectPropertyAddress = AudioObjectPropertyAddress()
-        if inputVolume == 0.0 {
-            address.mSelector = AudioObjectPropertySelector(kAudioDevicePropertyMute)
-        } else {
-            address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
-        }
         address.mScope = AudioObjectPropertyScope(kAudioDevicePropertyScopeOutput)
         address.mElement = AudioObjectPropertyElement(kAudioObjectPropertyElementMaster)
+        address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
         return AudioObjectSetPropertyData(defaultDeviceID, &address, 0, nil, size, &inputVolume)
     }
+    
+    private func setMute( mute: Int) -> OSStatus {
+        var muteVal: Int = mute
+        var address: AudioObjectPropertyAddress = AudioObjectPropertyAddress()
+        address.mSelector = AudioObjectPropertySelector(kAudioDevicePropertyMute)
+        let size: UInt32 = UInt32(MemoryLayout.size(ofValue: muteVal))
+        address.mScope = AudioObjectPropertyScope(kAudioDevicePropertyScopeOutput)
+        address.mElement = AudioObjectPropertyElement(kAudioObjectPropertyElementMaster)
+        return AudioObjectSetPropertyData(defaultDeviceID, &address, 0, nil, size, &muteVal)
+    }
 }
 
 class CustomSliderCell: NSSliderCell {