removed mute.caf dependency (creating silence.wav in runtime)

MuteDetector.xcodeproj/project.pbxproj

@@ -23,7 +23,6 @@
 		2CAFACD01855341B005407DE /* MuteDetectorTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 2CAFACCF1855341B005407DE /* MuteDetectorTests.m */; };
 		2CAFACDA18553580005407DE /* AVFoundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 2CAFACD91855357F005407DE /* AVFoundation.framework */; };
 		2CAFACE1185536DE005407DE /* SKMuteSwitchDetector.m in Sources */ = {isa = PBXBuildFile; fileRef = 2CAFACE0185536DE005407DE /* SKMuteSwitchDetector.m */; };
-		2CAFACE318553A2D005407DE /* mute.caf in Resources */ = {isa = PBXBuildFile; fileRef = 2CAFACE218553A2D005407DE /* mute.caf */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -59,7 +58,6 @@
 		2CAFACD91855357F005407DE /* AVFoundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = AVFoundation.framework; path = System/Library/Frameworks/AVFoundation.framework; sourceTree = SDKROOT; };
 		2CAFACDF185536DE005407DE /* SKMuteSwitchDetector.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SKMuteSwitchDetector.h; sourceTree = "<group>"; };
 		2CAFACE0185536DE005407DE /* SKMuteSwitchDetector.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SKMuteSwitchDetector.m; sourceTree = "<group>"; };
-		2CAFACE218553A2D005407DE /* mute.caf */ = {isa = PBXFileReference; lastKnownFileType = file; path = mute.caf; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -121,7 +119,6 @@
 		2CAFACAA1855341B005407DE /* MuteDetector */ = {
 			isa = PBXGroup;
 			children = (
-				2CAFACE218553A2D005407DE /* mute.caf */,
 				2CAFACDF185536DE005407DE /* SKMuteSwitchDetector.h */,
 				2CAFACE0185536DE005407DE /* SKMuteSwitchDetector.m */,
 				2CAFACB31855341B005407DE /* SKAppDelegate.h */,
@@ -244,7 +241,6 @@
 				2CAFACBD1855341B005407DE /* Images.xcassets in Resources */,
 				2CAFACAF1855341B005407DE /* InfoPlist.strings in Resources */,
 				2CAFACB81855341B005407DE /* Main.storyboard in Resources */,
-				2CAFACE318553A2D005407DE /* mute.caf in Resources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -477,6 +473,7 @@
 				2CAFACD51855341B005407DE /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 		2CAFACD61855341B005407DE /* Build configuration list for PBXNativeTarget "MuteDetectorTests" */ = {
 			isa = XCConfigurationList;
@@ -485,6 +482,7 @@
 				2CAFACD81855341B005407DE /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 /* End XCConfigurationList section */
 	};

MuteDetector/SKMuteSwitchDetector.m

@@ -10,6 +10,8 @@
 #import "SKMuteSwitchDetector.h"
 #import <AudioToolbox/AudioToolbox.h>
 
+#define SAMPLE_RATE 44000
+#define SAMPLES 0.2
 
 void MuteSoundPlaybackComplete(SystemSoundID  ssID,void* clientData){
 
@@ -24,15 +26,60 @@ void MuteSoundPlaybackComplete(SystemSoundID  ssID,void* clientData){
     AudioServicesDisposeSystemSoundID(soundId);
 }
 
+BOOL createSoundFileIfRequired(NSString* soundFile) {
+    if ([[NSFileManager defaultManager] fileExistsAtPath:soundFile isDirectory:NO])
+        return YES;
+
+    NSUInteger length = SAMPLE_RATE * SAMPLES * 2; // 2 bytes per sample
+    NSUInteger temp;
+    // initialize with room for RIFF chunk (36) + "data" header from data chunk + actual sound data
+    NSMutableData *data = [NSMutableData dataWithCapacity:(length + 36 + 4)];
+
+    [data appendData:[@"RIFF" dataUsingEncoding:NSASCIIStringEncoding]];
+    temp = length + 36;
+    [data appendData:[NSData dataWithBytes:&temp length:4]];
+    [data appendData:[@"WAVE" dataUsingEncoding:NSASCIIStringEncoding]];
+    [data appendData:[@"fmt " dataUsingEncoding:NSASCIIStringEncoding]];
+    temp = 16;
+    [data appendData:[NSData dataWithBytes:&temp length:4]];
+    temp = 1;
+    [data appendData:[NSData dataWithBytes:&temp length:2]];
+    [data appendData:[NSData dataWithBytes:&temp length:2]];
+    temp = SAMPLE_RATE;
+    [data appendData:[NSData dataWithBytes:&temp length:4]];
+    temp *= 2;
+    [data appendData:[NSData dataWithBytes:&temp length:4]];
+    temp = 2;
+    [data appendData:[NSData dataWithBytes:&temp length:2]];
+    temp = 16;
+    [data appendData:[NSData dataWithBytes:&temp length:2]];
+    [data appendData:[@"data" dataUsingEncoding:NSASCIIStringEncoding]];
+    [data appendData:[NSData dataWithBytes:&length length:4]];
+    temp = 0;
+
+    NSData *nullByte = [NSData dataWithBytes:&temp length:1];
+
+    for (NSUInteger i = 0; i < length; i++)
+        [data appendData:nullByte];
+
+    return [data writeToFile:soundFile atomically:YES];
+}
+
 @implementation SKMuteSwitchDetector
 
 + (void)checkSwitch:(SKMuteSwitchDetectorBlock)andPerform {
     if (!andPerform) return;
 
-    NSURL* url = [[NSBundle mainBundle] URLForResource:@"mute" withExtension:@"caf"];
+    NSString *soundFile = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches/silence.wav"];
+
+    if (!createSoundFileIfRequired(soundFile)) {
+        andPerform(NO, NO);
+        return;
+    }
+
     SystemSoundID soundId;
 
-    if (AudioServicesCreateSystemSoundID((__bridge CFURLRef)url, &soundId) == kAudioServicesNoError){
+    if (AudioServicesCreateSystemSoundID((__bridge CFURLRef)[NSURL fileURLWithPath:soundFile], &soundId) == kAudioServicesNoError){
         UInt32 yes = 1;
         AudioServicesSetProperty(kAudioServicesPropertyIsUISound, sizeof(soundId),&soundId,sizeof(yes), &yes);