From 3f4f07450bc7f5167e870c576c9af9170f8082c7 Mon Sep 17 00:00:00 2001
From: "Stephen (Alex) Wallen" <wallenstephen@outlook.com>
Date: Tue, 29 Aug 2023 18:17:29 -1000
Subject: [PATCH] feat: allow overriding curve

---
 lib/scroll_to_index.dart | 33 ++++++++++++++++++++-------------
 1 file changed, 20 insertions(+), 13 deletions(-)

diff --git a/lib/scroll_to_index.dart b/lib/scroll_to_index.dart
index 7b37c6b..81ca49e 100644
--- a/lib/scroll_to_index.dart
+++ b/lib/scroll_to_index.dart
@@ -210,9 +210,12 @@ mixin AutoScrollControllerMixin on ScrollController
             duration: duration, preferPosition: preferPosition));
   }
 
-  Future _scrollToIndex(int index,
-      {Duration duration: scrollAnimationDuration,
-      AutoScrollPosition? preferPosition}) async {
+  Future _scrollToIndex(
+    int index, {
+    Duration duration: scrollAnimationDuration,
+    AutoScrollPosition? preferPosition,
+    Curve curve = Curves.ease,
+  }) async {
     assert(duration > Duration.zero);
 
     // In listView init or reload case, widget state of list item may not be ready for query.
@@ -240,7 +243,7 @@ mixin AutoScrollControllerMixin on ScrollController
 
       await _bringIntoViewportIfNeed(index, preferPosition,
           (double offset) async {
-        await animateTo(offset, duration: duration, curve: Curves.ease);
+        await animateTo(offset, duration: duration, curve: curve);
         await _waitForWidgetStateBuild();
         return null;
       });
@@ -268,12 +271,12 @@ mixin AutoScrollControllerMixin on ScrollController
         prevOffset = currentOffset;
         final nearest = _getNearestIndex(index);
 
-        if (tagMap[nearest ?? 0] == null) 
+        if (tagMap[nearest ?? 0] == null)
           return null;
 
         final moveTarget =
             _forecastMoveUnit(index, nearest, usedSuggestedRowHeightIfAny)!;
-        
+
         // assume suggestRowHeight will move to correct offset in just one time.
         // if the rule doesn't work (in variable row height case), we will use backup solution (non-suggested way)
         final suggestedDuration =
@@ -286,7 +289,7 @@ mixin AutoScrollControllerMixin on ScrollController
         spentDuration += suggestedDuration ?? moveDuration;
         final oldOffset = offset;
         await animateTo(currentOffset,
-            duration: suggestedDuration ?? moveDuration, curve: Curves.ease);
+            duration: suggestedDuration ?? moveDuration, curve: curve);
         await _waitForWidgetStateBuild();
         if (!hasClients || offset == oldOffset) {
           // already scroll to begin or end
@@ -303,9 +306,11 @@ mixin AutoScrollControllerMixin on ScrollController
           if (finalOffset != offset) {
             _isAutoScrolling = true;
             final remaining = duration - spentDuration;
-            await animateTo(finalOffset,
-                duration: remaining <= Duration.zero ? _millisecond : remaining,
-                curve: Curves.ease);
+            await animateTo(
+              finalOffset,
+              duration: remaining <= Duration.zero ? _millisecond : remaining,
+              curve: curve,
+            );
             await _waitForWidgetStateBuild();
 
             // not sure why it doesn't scroll to the given offset, try more within 3 times
@@ -315,7 +320,7 @@ mixin AutoScrollControllerMixin on ScrollController
                   i < count && hasClients && offset != finalOffset;
                   i++) {
                 await animateTo(finalOffset,
-                    duration: _millisecond, curve: Curves.ease);
+                    duration: _millisecond, curve: curve);
                 await _waitForWidgetStateBuild();
               }
             }
@@ -379,7 +384,7 @@ mixin AutoScrollControllerMixin on ScrollController
     } else {
       final offsetToLastState =
           _offsetToRevealInViewport(currentNearestIndex, alignment);
-      
+
       absoluteOffsetToViewport = offsetToLastState?.offset;
       if (absoluteOffsetToViewport == null)
         absoluteOffsetToViewport = defaultScrollDistanceOffset;
@@ -646,7 +651,9 @@ class AutoScrollTagState<W extends AutoScrollTag> extends State<W>
   }
 }
 
-Widget buildHighlightTransition({required BuildContext context, required Animation<double> highlight, 
+Widget buildHighlightTransition(
+    {required BuildContext context,
+    required Animation<double> highlight,
   required Widget child, Color? background, Color? highlightColor}) {
   return DecoratedBoxTransition(
     decoration: DecorationTween(