Added SwiftPM support

Package.swift

@@ -0,0 +1,21 @@
+// swift-tools-version:5.2
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "TouchVisualizer",
+    platforms: [.iOS(.v9)],
+    products: [
+        .library(
+            name: "TouchVisualizer",
+            targets: ["TouchVisualizer"]),
+    ],
+    targets: [
+        .target(
+            name: "TouchVisualizer",
+            path: "TouchVisualizer",
+            exclude: ["Info.plist"]
+        )
+    ]
+)

TouchVisualizer/UIWindow+Swizzle.swift

@@ -7,9 +7,10 @@ import UIKit
 
 fileprivate var isSwizzled = false
 
-@available(iOS 8.0, *)
+@available(iOSApplicationExtension, unavailable)
 extension UIWindow {
-
+
+    @available(iOS 8.0, *)
 	public func swizzle() {
         guard isSwizzled == false else {
             return
@@ -30,6 +31,7 @@ extension UIWindow {
 }
 
 // MARK: - Swizzle
+@available(iOSApplicationExtension, unavailable)
 extension UIWindow {
     @objc public func swizzledSendEvent(_ event: UIEvent) {
         Visualizer.sharedInstance.handleEvent(event)

TouchVisualizer/Visualizer.swift

@@ -5,7 +5,8 @@
 
 import UIKit
 
-final public class Visualizer:NSObject {
+@available(iOSApplicationExtension, unavailable)
+final public class Visualizer: NSObject {
 
     // MARK: - Public Variables
     static public let sharedInstance = Visualizer()
@@ -57,6 +58,7 @@ final public class Visualizer:NSObject {
     }
 }
 
+@available(iOSApplicationExtension, unavailable)
 extension Visualizer {
     public class func isEnabled() -> Bool {
         return sharedInstance.enabled
@@ -182,6 +184,7 @@ extension Visualizer {
     }
 }
 
+@available(iOSApplicationExtension, unavailable)
 extension Visualizer {
     public func warnIfSimulator() {
         #if targetEnvironment(simulator)