From 00a2d672bf609a3cb396a4303868804e8d376fa8 Mon Sep 17 00:00:00 2001
From: Ivan Misuno <ivan.misuno@booking.com>
Date: Fri, 1 Jan 2016 16:49:04 +0100
Subject: [PATCH] Add Reactive bindings for UIBarButtonItem

---
 ReactiveUIKit.xcodeproj/project.pbxproj |  4 ++
 ReactiveUIKit/UIBarButtonItem.swift     | 63 +++++++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 ReactiveUIKit/UIBarButtonItem.swift

diff --git a/ReactiveUIKit.xcodeproj/project.pbxproj b/ReactiveUIKit.xcodeproj/project.pbxproj
index 1366de0..1553d01 100644
--- a/ReactiveUIKit.xcodeproj/project.pbxproj
+++ b/ReactiveUIKit.xcodeproj/project.pbxproj
@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		782B49D81C36D52100E5979D /* UIBarButtonItem.swift in Sources */ = {isa = PBXBuildFile; fileRef = 782B49D71C36D52100E5979D /* UIBarButtonItem.swift */; };
 		EC9549321BF1D8A7000FC2BF /* UICollectionView.swift in Sources */ = {isa = PBXBuildFile; fileRef = EC9549311BF1D8A7000FC2BF /* UICollectionView.swift */; };
 		EC9549341BF1DC52000FC2BF /* UIControl.swift in Sources */ = {isa = PBXBuildFile; fileRef = EC9549331BF1DC52000FC2BF /* UIControl.swift */; };
 		EC9549361BF1DE78000FC2BF /* UIButton.swift in Sources */ = {isa = PBXBuildFile; fileRef = EC9549351BF1DE78000FC2BF /* UIButton.swift */; };
@@ -66,6 +67,7 @@
 /* Begin PBXFileReference section */
 		16E125A11BF5056C00543EFB /* ReactiveUIKit.podspec */ = {isa = PBXFileReference; lastKnownFileType = text; path = ReactiveUIKit.podspec; sourceTree = "<group>"; };
 		16E125A21BF5056C00543EFB /* README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };
+		782B49D71C36D52100E5979D /* UIBarButtonItem.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UIBarButtonItem.swift; sourceTree = "<group>"; };
 		EC9549311BF1D8A7000FC2BF /* UICollectionView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UICollectionView.swift; sourceTree = "<group>"; };
 		EC9549331BF1DC52000FC2BF /* UIControl.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UIControl.swift; sourceTree = "<group>"; };
 		EC9549351BF1DE78000FC2BF /* UIButton.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UIButton.swift; sourceTree = "<group>"; };
@@ -165,6 +167,7 @@
 			children = (
 				ECB7A5441BEB71E10034053A /* ReactiveUIKit.h */,
 				ECB7A5631BEB72380034053A /* UIView.swift */,
+				782B49D71C36D52100E5979D /* UIBarButtonItem.swift */,
 				ECB7A55C1BEB72380034053A /* UIBarItem.swift */,
 				ECB7A55D1BEB72380034053A /* UIImageView.swift */,
 				ECB7A55E1BEB72380034053A /* UILabel.swift */,
@@ -377,6 +380,7 @@
 				EC95493A1BF1E12E000FC2BF /* UISegmentedControl.swift in Sources */,
 				EC9549341BF1DC52000FC2BF /* UIControl.swift in Sources */,
 				EC95493E1BF1E286000FC2BF /* UISwitch.swift in Sources */,
+				782B49D81C36D52100E5979D /* UIBarButtonItem.swift in Sources */,
 				ECB7A56C1BEB72380034053A /* UIView.swift in Sources */,
 				ECB7A5651BEB72380034053A /* UIBarItem.swift in Sources */,
 				ECB7A5691BEB72380034053A /* UIProgressView.swift in Sources */,
diff --git a/ReactiveUIKit/UIBarButtonItem.swift b/ReactiveUIKit/UIBarButtonItem.swift
new file mode 100644
index 0000000..f55c56e
--- /dev/null
+++ b/ReactiveUIKit/UIBarButtonItem.swift
@@ -0,0 +1,63 @@
+//
+//  UIBarButtonItem.swift
+//  ReactiveUIKit
+//
+//  Created by Ivan Misuno on 01/01/16.
+//  Copyright © 2016 Srdan Rasic. All rights reserved.
+//
+
+import UIKit
+import ReactiveKit
+import ReactiveFoundation
+
+@objc class RKUIBarButtonItemHelper: NSObject
+{
+    weak var barButtonItem: UIBarButtonItem?
+    let observer: Void -> Void
+
+    init(barButtonItem: UIBarButtonItem, observer: Void -> Void) {
+        self.barButtonItem = barButtonItem
+        self.observer = observer
+        super.init()
+        if barButtonItem.target != nil {
+            NSLog("Hijacking existing UIBarButtonItem's target and action: \(barButtonItem)")
+        }
+        barButtonItem.target = self
+        barButtonItem.action = Selector("eventHandler:")
+    }
+
+    func eventHandler(sender: AnyObject) {
+        observer()
+    }
+
+    deinit {
+        barButtonItem?.target = nil
+    }
+}
+
+extension UIBarButtonItem {
+
+    private struct AssociatedKeys {
+        static var BarButtonItemActionKey = "r_BarButtonItemActionKey"
+        static var BarButtonItemBondHelperKey = "r_BarButtonItemBondHelperKey"
+    }
+
+    public var rAction: ActiveStream<Void> {
+        if let rAction: AnyObject = objc_getAssociatedObject(self, &AssociatedKeys.BarButtonItemActionKey) {
+            return rAction as! ActiveStream<Void>
+        } else {
+            var capturedObserver: (Void -> Void)! = nil
+
+            let rAction = ActiveStream<Void> { observer in
+                capturedObserver = observer
+                return nil
+            }
+
+            let barButtonItemHelper = RKUIBarButtonItemHelper(barButtonItem: self, observer: capturedObserver)
+
+            objc_setAssociatedObject(self, &AssociatedKeys.BarButtonItemBondHelperKey, barButtonItemHelper, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
+            objc_setAssociatedObject(self, &AssociatedKeys.BarButtonItemActionKey, rAction, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
+            return rAction
+        }
+    }
+}