feat(ios): add direction to ListView scrolling (#14130)

* feat(ios): add direction to ListView scrolling

* Update iphone/Classes/TiUIListView.m

Co-authored-by: Hans Knöchel <[email protected]>

* fix: fix “direction” event attribute default

* fix: fix incorrect type

* chore: align “unknown” value with Android, update docs

---------

Co-authored-by: Hans Knöchel <[email protected]>
Co-authored-by: Hans Knöchel <[email protected]>

Author: m1ga

android/modules/ui/src/java/ti/modules/titanium/ui/widget/listview/TiListView.java

@@ -153,6 +153,8 @@ public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy)
 						payload.put(TiC.PROPERTY_DIRECTION, "up");
 					} else if (dy < 0) {
 						payload.put(TiC.PROPERTY_DIRECTION, "down");
+					} else {
+						payload.put(TiC.PROPERTY_DIRECTION, "unknown");
 					}
 					payload.put(TiC.EVENT_PROPERTY_VELOCITY, 0);
 					if (continuousUpdate) {

apidoc/Titanium/UI/ListView.yml

@@ -648,7 +648,7 @@ events:
         ipad: 5.4.0
     properties:
       - name: direction
-        summary: Direction of the scroll either 'up', or 'down'.
+        summary: Direction of the scroll either 'up', 'down' or 'unknown'.
         type: String
 
       - name: velocity

apidoc/Titanium/UI/TableView.yml

@@ -453,7 +453,7 @@ events:
     since: { android: "2.1.0", iphone: "2.1.0", ipad: "2.1.0" }
     properties:
       - name: direction
-        summary: Direction of the swipe, either `left` or `right`.
+        summary: Direction of the swipe, either `left`, `right` or `unknown`.
         type: String
 
       - name: index

iphone/Classes/TiUIListView.m

@@ -24,6 +24,7 @@ @interface TiUIListView ()
 @property (nonatomic, readonly) TiUIListViewProxy *listViewProxy;
 @property (nonatomic, copy, readwrite) NSString *searchString;
 @property (nonatomic, copy, readwrite) NSString *searchedString;
+@property (nonatomic, assign) CGFloat lastContentOffset;
 @end
 
 static TiViewProxy *FindViewProxyWithBindIdContainingPoint(UIView *view, CGPoint point);
@@ -79,8 +80,8 @@ @implementation TiUIListView {
   BOOL isSearched;
   UIView *dimmingView;
   BOOL isSearchBarInNavigation;
-  int lastVisibleItem;
-  int lastVisibleSection;
+  NSInteger lastVisibleItem;
+  NSInteger lastVisibleSection;
   BOOL forceUpdates;
 }
 
@@ -2011,6 +2012,15 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
         TiUIListSectionProxy *section;
         CGFloat topSpacing = scrollView.contentOffset.y + scrollView.adjustedContentInset.top;
 
+        NSString *direction = @"unknown";
+
+        if (self.lastContentOffset > scrollView.contentOffset.y) {
+          direction = @"down";
+        } else if (self.lastContentOffset < scrollView.contentOffset.y) {
+          direction = @"up";
+        }
+        self.lastContentOffset = scrollView.contentOffset.y;
+
         if ([indexPaths count] > 0) {
           NSIndexPath *indexPath = [self pathForSearchPath:[indexPaths objectAtIndex:0]];
           NSUInteger visibleItemCount = [indexPaths count];
@@ -2022,6 +2032,7 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
           [eventArgs setValue:section forKey:@"firstVisibleSection"];
           [eventArgs setValue:[section itemAtIndex:[indexPath row]] forKey:@"firstVisibleItem"];
           [eventArgs setValue:NUMINTEGER(topSpacing) forKey:@"top"];
+          [eventArgs setValue:direction forKey:@"direction"];
 
           if (lastVisibleItem != [indexPath row] || lastVisibleSection != [indexPath section] || forceUpdates) {
             // only log if the item changes or forced
@@ -2038,6 +2049,7 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
           [eventArgs setValue:section forKey:@"firstVisibleSection"];
           [eventArgs setValue:NUMINTEGER(-1) forKey:@"firstVisibleItem"];
           [eventArgs setValue:NUMINTEGER(topSpacing) forKey:@"top"];
+          [eventArgs setValue:direction forKey:@"direction"];
         }
       });
     }
@@ -2110,7 +2122,7 @@ - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
 - (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
 {
   if ([[self proxy] _hasListeners:@"scrolling"]) {
-    NSString *direction = nil;
+    NSString *direction = @"unknown";
 
     if (velocity.y > 0) {
       direction = @"up";