From 344ca57f4b6e98b9609e9e869fe0ba4a5d999bec Mon Sep 17 00:00:00 2001
From: Simon Jackson <none@none>
Date: Wed, 4 Jan 2017 13:18:28 +0000
Subject: [PATCH] Updated VSS / HSS to handle pages with interactable
 components. Interactables mess with the Pointer Down/Up events that the
 control used when a mouse is used, so implementation changes to suit.

--HG--
branch : develop_5.3
---
 Scripts/Layout/HorizontalScrollSnap.cs | 17 +++++++++++------
 Scripts/Layout/ScrollSnapBase.cs       | 12 ++----------
 Scripts/Layout/VerticalScrollSnap.cs   | 21 +++++++++++++++------
 3 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/Scripts/Layout/HorizontalScrollSnap.cs b/Scripts/Layout/HorizontalScrollSnap.cs
index 58b3578..b8361c3 100644
--- a/Scripts/Layout/HorizontalScrollSnap.cs
+++ b/Scripts/Layout/HorizontalScrollSnap.cs
@@ -43,19 +43,22 @@ namespace UnityEngine.UI.Extensions
             }
 
             CurrentPage = GetPageforPosition(_screensContainer.localPosition);
-            
+
             //If the container is moving check if it needs to settle on a page
-            if (!_pointerDown && (_scroll_rect.velocity.x > 0.01 || _scroll_rect.velocity.x < 0.01))
+            if (!_pointerDown)
             {
-                // if the pointer is released and is moving slower than the threshold, then just land on a page
-                if (IsRectMovingFasterThanThreshold(0))
+                if (_scroll_rect.velocity.x > 0.01 || _scroll_rect.velocity.x < 0.01)
                 {
-                    ScrollToClosestElement();
+                    //if the pointer is released and is moving slower than the threshold, then just land on a page
+                    if (IsRectMovingSlowerThanThreshold(0))
+                    {
+                        ScrollToClosestElement();
+                    }
                 }
             }
         }
 
-        private bool IsRectMovingFasterThanThreshold(float startingSpeed)
+        private bool IsRectMovingSlowerThanThreshold(float startingSpeed)
         {
             return (_scroll_rect.velocity.x > startingSpeed && _scroll_rect.velocity.x < SwipeVelocityThreshold) ||
                                 (_scroll_rect.velocity.x < startingSpeed && _scroll_rect.velocity.x > -SwipeVelocityThreshold);
@@ -195,6 +198,8 @@ namespace UnityEngine.UI.Extensions
         /// <param name="eventData"></param>
         public void OnEndDrag(PointerEventData eventData)
         {
+            _pointerDown = false;
+
             if (_scroll_rect.horizontal)
             {
                 if (UseFastSwipe)
diff --git a/Scripts/Layout/ScrollSnapBase.cs b/Scripts/Layout/ScrollSnapBase.cs
index 67fabf2..34c81ce 100644
--- a/Scripts/Layout/ScrollSnapBase.cs
+++ b/Scripts/Layout/ScrollSnapBase.cs
@@ -4,7 +4,7 @@ using UnityEngine.EventSystems;
 
 namespace UnityEngine.UI.Extensions
 {
-    public class ScrollSnapBase : MonoBehaviour, IBeginDragHandler, IDragHandler, IPointerDownHandler, IPointerUpHandler
+    public class ScrollSnapBase : MonoBehaviour, IBeginDragHandler, IDragHandler
     {
         internal RectTransform _screensContainer;
         internal bool _isVertical;
@@ -404,6 +404,7 @@ namespace UnityEngine.UI.Extensions
         /// <param name="eventData"></param>
         public void OnBeginDrag(PointerEventData eventData)
         {
+            _pointerDown = true;
             _settled = false;
             StartScreenChange();
             _startPosition = _screensContainer.localPosition;
@@ -418,15 +419,6 @@ namespace UnityEngine.UI.Extensions
             _lerp = false;
         }
 
-        public void OnPointerDown(PointerEventData eventData)
-        {
-            _pointerDown = true;
-        }
-
-        public void OnPointerUp(PointerEventData eventData)
-        {
-            _pointerDown = false;
-        }
         #endregion
     }
 }
\ No newline at end of file
diff --git a/Scripts/Layout/VerticalScrollSnap.cs b/Scripts/Layout/VerticalScrollSnap.cs
index 0d92abb..b563b46 100644
--- a/Scripts/Layout/VerticalScrollSnap.cs
+++ b/Scripts/Layout/VerticalScrollSnap.cs
@@ -45,16 +45,23 @@ namespace UnityEngine.UI.Extensions
             CurrentPage = GetPageforPosition(_screensContainer.localPosition);
 
             //If the container is moving check if it needs to settle on a page
-            if (!_pointerDown && (_scroll_rect.velocity.y > 0.01 || _scroll_rect.velocity.y < -0.01))
+            if (!_pointerDown)
             {
-                // if the pointer is released and is moving slower than the threshold, then just land on a page
-                if ((_scroll_rect.velocity.y > 0 && _scroll_rect.velocity.y < SwipeVelocityThreshold) ||
-                    (_scroll_rect.velocity.y < 0 && _scroll_rect.velocity.y > -SwipeVelocityThreshold))
-                {
-                    ScrollToClosestElement();
+                if (_scroll_rect.velocity.y > 0.01 || _scroll_rect.velocity.y < -0.01)
+            {
+                    // if the pointer is released and is moving slower than the threshold, then just land on a page
+                    if (IsRectMovingSlowerThanThreshold(0))
+                    {
+                        ScrollToClosestElement();
+                    }
                 }
             }
+        }
 
+        private bool IsRectMovingSlowerThanThreshold(float startingSpeed)
+        {
+            return (_scroll_rect.velocity.y > startingSpeed && _scroll_rect.velocity.y < SwipeVelocityThreshold) ||
+                                (_scroll_rect.velocity.y < startingSpeed && _scroll_rect.velocity.y > -SwipeVelocityThreshold);
         }
 
         public void DistributePages()
@@ -191,6 +198,8 @@ namespace UnityEngine.UI.Extensions
         /// <param name="eventData"></param>
         public void OnEndDrag(PointerEventData eventData)
         {
+            _pointerDown = false;
+
             if (_scroll_rect.vertical)
             {
                 if (UseFastSwipe)