From aa7fe56bb4178d6df77f18442622397afb9dbe6f Mon Sep 17 00:00:00 2001
From: Dave Bennett <dave@primedcanvasmedia.com>
Date: Wed, 26 Apr 2017 13:55:25 +0100
Subject: [PATCH] Modal gestureEnabled (#1243)

* Fix Modal Gestures

* Update StackNavigator.md for gesturesEnabled to include modals again

* Remove modal gesture todo

* Gesture response distance top, side => vertical, horizontal
---
 docs/api/navigators/StackNavigator.md |  2 +-
 src/views/CardStack.js                | 24 ++++++++++++++----------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/docs/api/navigators/StackNavigator.md b/docs/api/navigators/StackNavigator.md
index 81800af0..e73dde31 100644
--- a/docs/api/navigators/StackNavigator.md
+++ b/docs/api/navigators/StackNavigator.md
@@ -138,7 +138,7 @@ Color for material ripple (Android >= 5.0 only)
 
 #### `gesturesEnabled`
 
-Whether you can use gestures to dismiss this screen. Defaults to true on iOS, false on Android. This value when set is only respected in `mode` == `card`.
+Whether you can use gestures to dismiss this screen. Defaults to true on iOS, false on Android.
 
 ### Navigator Props
 
diff --git a/src/views/CardStack.js b/src/views/CardStack.js
index 23c6663a..0b095c69 100644
--- a/src/views/CardStack.js
+++ b/src/views/CardStack.js
@@ -82,7 +82,8 @@ const RESPOND_THRESHOLD = 12;
 /**
  * The distance of touch start from the edge of the screen where the gesture will be recognized
  */
-const GESTURE_RESPONSE_DISTANCE = 35;
+const GESTURE_RESPONSE_DISTANCE_HORIZONTAL = 35;
+const GESTURE_RESPONSE_DISTANCE_VERTICAL = 135;
 
 const animatedSubscribeValue = (animatedValue: Animated.Value) => {
   if (!animatedValue.__isNative) {
@@ -260,7 +261,7 @@ class CardStack extends Component {
         if (index !== scene.index) {
           return false;
         }
-        const isVertical = false; // todo: bring back gestures for mode=modal
+        const isVertical = mode === 'modal';
         const immediateIndex = this._immediateIndex == null
           ? index
           : this._immediateIndex;
@@ -275,8 +276,12 @@ class CardStack extends Component {
 
         // Measure the distance from the touch to the edge of the screen
         const screenEdgeDistance = currentDragPosition - currentDragDistance;
-        // GESTURE_RESPONSE_DISTANCE is about 30 or 35
-        if (screenEdgeDistance > GESTURE_RESPONSE_DISTANCE) {
+        // Compare to the gesture distance relavant to card or modal
+        const gestureResponseDistance = isVertical
+          ? GESTURE_RESPONSE_DISTANCE_VERTICAL
+          : GESTURE_RESPONSE_DISTANCE_HORIZONTAL;
+        // GESTURE_RESPONSE_DISTANCE is about 30 or 35. Or 135 for modals
+        if (screenEdgeDistance > gestureResponseDistance) {
           // Reject touches that started in the middle of the screen
           return false;
         }
@@ -293,7 +298,7 @@ class CardStack extends Component {
       onPanResponderMove: (event: any, gesture: any) => {
         // Handle the moving touches for our granted responder
         const layout = this.props.layout;
-        const isVertical = false;
+        const isVertical = mode === 'modal';
         const startValue = this._gestureStartValue;
         const axis = isVertical ? 'dy' : 'dx';
         const distance = isVertical
@@ -314,7 +319,7 @@ class CardStack extends Component {
           return;
         }
         this._isResponding = false;
-        const isVertical = false;
+        const isVertical = mode === 'modal';
         const velocity = gesture[isVertical ? 'vy' : 'vx'];
         const immediateIndex = this._immediateIndex == null
           ? index
@@ -345,10 +350,9 @@ class CardStack extends Component {
     });
 
     const { options } = this._getScreenDetails(scene);
-    const gesturesEnabled = mode === 'card' &&
-      (typeof options.gesturesEnabled === 'boolean'
-        ? options.gesturesEnabled
-        : Platform.OS === 'ios');
+    const gesturesEnabled = typeof options.gesturesEnabled === 'boolean'
+      ? options.gesturesEnabled
+      : Platform.OS === 'ios';
 
     const handlers = gesturesEnabled ? responder.panHandlers : {};