From 47f18bdb175af5f76228b86b552e7bbe77db3667 Mon Sep 17 00:00:00 2001
From: Valentin Shergin <shergin@fb.com>
Date: Mon, 9 Jan 2017 00:09:38 -0800
Subject: [PATCH] Nobody outside RCTTouchHandler should treat it as
 UIGestureRecognizer subclass

Reviewed By: mmmulani

Differential Revision: D4387821

fbshipit-source-id: 8060772a5de669eeaca159ceac13b995d7518a1b
---
 React/Base/RCTRootView.m              |  2 +-
 React/Base/RCTTouchHandler.h          |  4 ++++
 React/Base/RCTTouchHandler.m          | 15 +++++++++++++++
 React/Views/RCTModalHostView.m        |  8 ++++----
 React/Views/RCTModalHostViewManager.m |  1 -
 5 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/React/Base/RCTRootView.m b/React/Base/RCTRootView.m
index ebaad7ddc..41d155555 100644
--- a/React/Base/RCTRootView.m
+++ b/React/Base/RCTRootView.m
@@ -380,7 +380,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
     _bridge = bridge;
     self.reactTag = reactTag;
     _touchHandler = [[RCTTouchHandler alloc] initWithBridge:_bridge];
-    [self addGestureRecognizer:_touchHandler];
+    [_touchHandler attachToView:self];
     [_bridge.uiManager registerRootView:self withSizeFlexibility:sizeFlexibility];
     self.layer.backgroundColor = NULL;
   }
diff --git a/React/Base/RCTTouchHandler.h b/React/Base/RCTTouchHandler.h
index d5f4cbb4e..6f2df0444 100644
--- a/React/Base/RCTTouchHandler.h
+++ b/React/Base/RCTTouchHandler.h
@@ -16,6 +16,10 @@
 @interface RCTTouchHandler : UIGestureRecognizer
 
 - (instancetype)initWithBridge:(RCTBridge *)bridge NS_DESIGNATED_INITIALIZER;
+
+- (void)attachToView:(UIView *)view;
+- (void)detachFromView:(UIView *)view;
+
 - (void)cancel;
 
 @end
diff --git a/React/Base/RCTTouchHandler.m b/React/Base/RCTTouchHandler.m
index 1c36073f8..b4d1d24ea 100644
--- a/React/Base/RCTTouchHandler.m
+++ b/React/Base/RCTTouchHandler.m
@@ -64,6 +64,21 @@
 
 RCT_NOT_IMPLEMENTED(- (instancetype)initWithTarget:(id)target action:(SEL)action)
 
+- (void)attachToView:(UIView *)view
+{
+  RCTAssert(self.view == nil, @"RCTTouchHandler already has attached view.");
+
+  [view addGestureRecognizer:self];
+}
+
+- (void)detachFromView:(UIView *)view
+{
+  RCTAssertParam(view);
+  RCTAssert(self.view == view, @"RCTTouchHandler attached to another view.");
+
+  [view removeGestureRecognizer:self];
+}
+
 typedef NS_ENUM(NSInteger, RCTTouchEventType) {
   RCTTouchEventTypeStart,
   RCTTouchEventTypeMove,
diff --git a/React/Views/RCTModalHostView.m b/React/Views/RCTModalHostView.m
index e41618161..adc776258 100644
--- a/React/Views/RCTModalHostView.m
+++ b/React/Views/RCTModalHostView.m
@@ -9,6 +9,8 @@
 
 #import "RCTModalHostView.h"
 
+#import <UIKit/UIKit.h>
+
 #import "RCTAssert.h"
 #import "RCTBridge.h"
 #import "RCTModalHostViewController.h"
@@ -16,8 +18,6 @@
 #import "RCTUIManager.h"
 #import "UIView+React.h"
 
-#import <UIKit/UIKit.h>
-
 @implementation RCTModalHostView
 {
   __weak RCTBridge *_bridge;
@@ -87,7 +87,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:coder)
 {
   RCTAssert(_reactSubview == nil, @"Modal view can only have one subview");
   [super insertReactSubview:subview atIndex:atIndex];
-  [subview addGestureRecognizer:_touchHandler];
+  [_touchHandler attachToView:subview];
   subview.autoresizingMask = UIViewAutoresizingFlexibleHeight |
                              UIViewAutoresizingFlexibleWidth;
 
@@ -99,7 +99,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:coder)
 {
   RCTAssert(subview == _reactSubview, @"Cannot remove view other than modal view");
   [super removeReactSubview:subview];
-  [subview removeGestureRecognizer:_touchHandler];
+  [_touchHandler detachFromView:subview];
   _reactSubview = nil;
 }
 
diff --git a/React/Views/RCTModalHostViewManager.m b/React/Views/RCTModalHostViewManager.m
index b228e0bde..8f99b5c73 100644
--- a/React/Views/RCTModalHostViewManager.m
+++ b/React/Views/RCTModalHostViewManager.m
@@ -12,7 +12,6 @@
 #import "RCTBridge.h"
 #import "RCTModalHostView.h"
 #import "RCTModalHostViewController.h"
-#import "RCTTouchHandler.h"
 #import "RCTShadowView.h"
 #import "RCTUtils.h"