improve vibration for incoming calls

Session.xcodeproj/project.pbxproj

@@ -142,6 +142,7 @@
 		7B7CB18B270591630079FF93 /* ShareLogsModal.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B7CB18A270591630079FF93 /* ShareLogsModal.swift */; };
 		7B7CB18E270D066F0079FF93 /* IncomingCallBanner.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B7CB18D270D066F0079FF93 /* IncomingCallBanner.swift */; };
 		7B7CB190270FB2150079FF93 /* MiniCallView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B7CB18F270FB2150079FF93 /* MiniCallView.swift */; };
+		7B7CB192271508AD0079FF93 /* Vibration.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B7CB191271508AD0079FF93 /* Vibration.swift */; };
 		7BC01A3E241F40AB00BC7C55 /* NotificationServiceExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BC01A3D241F40AB00BC7C55 /* NotificationServiceExtension.swift */; };
 		7BC01A42241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex in Embed App Extensions */ = {isa = PBXBuildFile; fileRef = 7BC01A3B241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 		7BCD116C27016062006330F1 /* WebRTCSession+DataChannel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7BCD116B27016062006330F1 /* WebRTCSession+DataChannel.swift */; };
@@ -1120,6 +1121,7 @@
 		7B7CB18A270591630079FF93 /* ShareLogsModal.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShareLogsModal.swift; sourceTree = "<group>"; };
 		7B7CB18D270D066F0079FF93 /* IncomingCallBanner.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = IncomingCallBanner.swift; sourceTree = "<group>"; };
 		7B7CB18F270FB2150079FF93 /* MiniCallView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MiniCallView.swift; sourceTree = "<group>"; };
+		7B7CB191271508AD0079FF93 /* Vibration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Vibration.swift; sourceTree = "<group>"; };
 		7BC01A3B241F40AB00BC7C55 /* SessionNotificationServiceExtension.appex */ = {isa = PBXFileReference; explicitFileType = "wrapper.app-extension"; includeInIndex = 0; path = SessionNotificationServiceExtension.appex; sourceTree = BUILT_PRODUCTS_DIR; };
 		7BC01A3D241F40AB00BC7C55 /* NotificationServiceExtension.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NotificationServiceExtension.swift; sourceTree = "<group>"; };
 		7BC01A3F241F40AB00BC7C55 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -2320,6 +2322,7 @@
 				C38EF23D255B6D66007E1867 /* UIView+OWS.h */,
 				C38EF23E255B6D66007E1867 /* UIView+OWS.m */,
 				C38EF2EF255B6DBB007E1867 /* Weak.swift */,
+				7B7CB191271508AD0079FF93 /* Vibration.swift */,
 			);
 			path = General;
 			sourceTree = "<group>";
@@ -4601,6 +4604,7 @@
 				C3BBE0A82554D4DE0050F1E3 /* JSON.swift in Sources */,
 				C352A36D2557858E00338F3E /* NSTimer+Proxying.m in Sources */,
 				C32C5A2D256DB849003C73A2 /* LKGroupUtilities.m in Sources */,
+				7B7CB192271508AD0079FF93 /* Vibration.swift in Sources */,
 				C3C2ABD22553C6C900C340D1 /* Data+SecureRandom.swift in Sources */,
 				B8856E09256F1676001CE70E /* UIDevice+featureSupport.swift in Sources */,
 				B8856DEF256F161F001CE70E /* NSString+SSK.m in Sources */,

Session/Calls/Views & Modals/IncomingCallBanner.swift

@@ -178,13 +178,11 @@ final class IncomingCallBanner: UIView, UIGestureRecognizerDelegate {
         UIView.animate(withDuration: 0.5, delay: 0, options: [], animations: {
             self.alpha = 1.0
         }, completion: nil)
-        vibrationTimer = WeakTimer.scheduledTimer(timeInterval: 0.5, target: self, userInfo: nil, repeats: true) { _ in
-            AudioServicesPlaySystemSound(kSystemSoundID_Vibrate)
-        }
+        Vibration.shared.startVibration()
     }
     
     public func dismiss() {
-        vibrationTimer?.invalidate()
+        Vibration.shared.stopVibrationIfPossible()
         UIView.animate(withDuration: 0.5, delay: 0, options: [], animations: {
             self.alpha = 0.0
         }, completion: { _ in

SessionUtilitiesKit/General/Vibration.swift

@@ -0,0 +1,19 @@
+import AudioToolbox
+
+public final class Vibration {
+    
+    public static let shared = Vibration()
+    
+    private var vibrationTimer: Timer?
+    
+    public func startVibration() {
+        vibrationTimer = Timer.scheduledTimer(withTimeInterval: 0.5, repeats: true) { _ in
+            AudioServicesPlaySystemSound(kSystemSoundID_Vibrate)
+        }
+    }
+    
+    public func stopVibrationIfPossible() {
+        vibrationTimer?.invalidate()
+        vibrationTimer = nil
+    }
+}