From 774f8de199ca4a6a5897c899bbe70777a7cf9792 Mon Sep 17 00:00:00 2001
From: Simon Jackson <darkside@zenithmoon.com>
Date: Sun, 5 Sep 2021 09:33:19 +0100
Subject: [PATCH] Resolves issue where the lower range value would become stuck
 when moved to the max value position

Resolves: https://bitbucket.org/UnityUIExtensions/unity-ui-extensions/issues/381/cant-move-range-slider-if-low-is-moved-to
---
 Runtime/Scripts/Controls/RangeSlider.cs | 56 +++++++++++++++----------
 1 file changed, 35 insertions(+), 21 deletions(-)

diff --git a/Runtime/Scripts/Controls/RangeSlider.cs b/Runtime/Scripts/Controls/RangeSlider.cs
index ceeb6da..4477017 100644
--- a/Runtime/Scripts/Controls/RangeSlider.cs
+++ b/Runtime/Scripts/Controls/RangeSlider.cs
@@ -533,31 +533,17 @@ namespace UnityEngine.UI.Extensions
             //HANDLE DRAG EVENTS
             m_LowOffset = m_HighOffset = Vector2.zero;
             Vector2 localMousePos;
-            if (m_HighHandleRect != null && RectTransformUtility.RectangleContainsScreenPoint(m_HighHandleRect, eventData.position, eventData.enterEventCamera))
+            if(m_LowHandleRect != null && LowValue == MaxValue && RectTransformUtility.RectangleContainsScreenPoint(m_LowHandleRect, eventData.position, eventData.enterEventCamera))
             {
-                //dragging the high value handle
-                if (RectTransformUtility.ScreenPointToLocalPointInRectangle(m_HighHandleRect, eventData.position, eventData.pressEventCamera, out localMousePos))
-                {
-                    m_HighOffset = localMousePos;
-                }
-                interactionState = InteractionState.High;
-                if (transition == Transition.ColorTint)
-                {
-                    targetGraphic = m_HighHandleRect.GetComponent<Graphic>();
-                }
+                SetToMoveLowValueHandle(m_LowHandleRect, eventData);
+            }
+            else if (m_HighHandleRect != null && RectTransformUtility.RectangleContainsScreenPoint(m_HighHandleRect, eventData.position, eventData.enterEventCamera))
+            {
+                SetToMoveHighValueHandle(m_HighHandleRect, eventData);
             }
             else if (m_LowHandleRect != null && RectTransformUtility.RectangleContainsScreenPoint(m_LowHandleRect, eventData.position, eventData.enterEventCamera))
             {
-                //dragging the low value handle
-                if (RectTransformUtility.ScreenPointToLocalPointInRectangle(m_LowHandleRect, eventData.position, eventData.pressEventCamera, out localMousePos))
-                {
-                    m_LowOffset = localMousePos;
-                }
-                interactionState = InteractionState.Low;
-                if (transition == Transition.ColorTint)
-                {
-                    targetGraphic = m_LowHandleRect.GetComponent<Graphic>();
-                }
+                SetToMoveLowValueHandle(m_LowHandleRect, eventData);
             }
             else
             {
@@ -575,6 +561,34 @@ namespace UnityEngine.UI.Extensions
             base.OnPointerDown(eventData);
         }
 
+        private void SetToMoveLowValueHandle(RectTransform transform, PointerEventData eventData)
+        {
+            //dragging the low value handle
+            if (RectTransformUtility.ScreenPointToLocalPointInRectangle(transform, eventData.position, eventData.pressEventCamera, out var localMousePos))
+            {
+                m_LowOffset = localMousePos;
+            }
+            interactionState = InteractionState.Low;
+            if (transition == Transition.ColorTint)
+            {
+                targetGraphic = m_LowHandleRect.GetComponent<Graphic>();
+            }
+        }
+
+        private void SetToMoveHighValueHandle(RectTransform transform, PointerEventData eventData)
+        {
+            //dragging the low value handle
+            if (RectTransformUtility.ScreenPointToLocalPointInRectangle(transform, eventData.position, eventData.pressEventCamera, out var localMousePos))
+            {
+                m_HighOffset = localMousePos;
+            }
+            interactionState = InteractionState.High;
+            if (transition == Transition.ColorTint)
+            {
+                targetGraphic = m_HighHandleRect.GetComponent<Graphic>();
+            }
+        }
+
         public virtual void OnDrag(PointerEventData eventData)
         {
             if (!MayDrag(eventData))