feat(all): add forceUpdates propterty to listView to improve scroll…

…ing event (#13830)

Co-authored-by: Chris Barber <chris@cb1inc.com>

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

@@ -562,6 +562,11 @@ private void processProperty(String name, Object value)
 			if (listView != null) {
 				listView.setContinousUpdate(TiConvert.toBoolean(value, false));
 			}
+		} else if (name.equals("forceUpdates")) {
+			final TiListView listView = getListView();
+			if (listView != null) {
+				listView.setForceUpdates(TiConvert.toBoolean(value, false));
+			}
 		}
 	}
 

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

@@ -56,6 +56,7 @@ public class TiListView extends TiSwipeRefreshLayout implements OnSearchChangeLi
 	private SelectionTracker tracker = null;
 	private boolean isScrolling = false;
 	private boolean continuousUpdate = false;
+	private boolean forceUpdate = false;
 	private int lastScrollDeltaY;
 	private int scrollOffsetX = 0;
 	private int scrollOffsetY = 0;
@@ -157,7 +158,8 @@ public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy)
 					if (continuousUpdate) {
 						if (lastVisibleItem != TiConvert.toInt(payload.get(TiC.PROPERTY_FIRST_VISIBLE_ITEM_INDEX))
 							|| lastVisibleSection
-								   != TiConvert.toInt(payload.get(TiC.PROPERTY_FIRST_VISIBLE_SECTION_INDEX))) {
+								   != TiConvert.toInt(payload.get(TiC.PROPERTY_FIRST_VISIBLE_SECTION_INDEX))
+							|| forceUpdate) {
 							proxy.fireSyncEvent(TiC.EVENT_SCROLLING, payload);
 							lastVisibleItem = TiConvert.toInt(payload.get(TiC.PROPERTY_FIRST_VISIBLE_ITEM_INDEX));
 							lastVisibleSection = TiConvert.toInt(payload.get(TiC.PROPERTY_FIRST_VISIBLE_SECTION_INDEX));
@@ -282,6 +284,7 @@ public boolean inSelectionHotspot(@NonNull MotionEvent e)
 		final boolean allowsMultipleSelection
 			= properties.optBoolean(TiC.PROPERTY_ALLOWS_MULTIPLE_SELECTION_DURING_EDITING, false);
 		continuousUpdate = properties.optBoolean(TiC.PROPERTY_CONTINUOUS_UPDATE, false);
+		forceUpdate = properties.optBoolean("forceUpdates", false);
 
 		if (properties.optBoolean(TiC.PROPERTY_FIXED_SIZE, false)) {
 			this.recyclerView.setHasFixedSize(true);
@@ -398,6 +401,8 @@ public KrollDict generateScrollPayload()
 				payload.put(TiC.PROPERTY_FIRST_VISIBLE_SECTION, null);
 				payload.put(TiC.PROPERTY_FIRST_VISIBLE_SECTION_INDEX, -1);
 			}
+
+			payload.put(TiC.PROPERTY_TOP, recyclerView.computeVerticalScrollOffset());
 		}
 
 		// Define visible item count.
@@ -817,6 +822,11 @@ public void setContinousUpdate(boolean value)
 		continuousUpdate = value;
 	}
 
+	public void setForceUpdates(boolean value)
+	{
+		forceUpdate = value;
+	}
+
 	public void update()
 	{
 		this.update(false);

apidoc/Titanium/UI/ListView.yml

@@ -388,7 +388,7 @@ events:
     summary: Fired when a list row has started moving.
     description: |
       This event can be used to change the UI once a new drag-and-drop interaction starts.
-      The event properties are available in Titanium SDK 12.0.0+ 
+      The event properties are available in Titanium SDK 12.0.0+
     since: "11.1.0"
     platforms: [android, iphone, ipad, macos]
     properties:
@@ -959,6 +959,16 @@ properties:
     platforms: [android, iphone, ipad, macos]
     since: 11.1.0
 
+  - name: forceUpdates
+    summary: Optimize the `continuousUpdate` scrolling event.
+    description: |
+        If `continuousUpdate` is enabled and you set `forceUpdates` to `true` it will fire the scrolling](Titanium.UI.ListView.scrolling) all the time.
+        Otherwise it will only update when a new item is scrolled in (default).
+    type: Boolean
+    default: false
+    platforms: [android, iphone, ipad, macos]
+    since: 12.3.0
+
   - name: keepSectionsInSearch
     summary: Determines if the section information is displayed in the search results when using the `searchText` property.
     description: |

iphone/Classes/TiUIListView.m

@@ -81,6 +81,7 @@ @implementation TiUIListView {
   BOOL isSearchBarInNavigation;
   int lastVisibleItem;
   int lastVisibleSection;
+  BOOL forceUpdates;
 }
 
 #ifdef TI_USE_AUTOLAYOUT
@@ -101,6 +102,7 @@ - (id)init
     _defaultItemTemplate = [[NSNumber numberWithUnsignedInteger:UITableViewCellStyleDefault] retain];
     _defaultSeparatorInsets = UIEdgeInsetsZero;
     _dimsBackgroundDuringPresentation = YES;
+    forceUpdates = NO;
   }
   return self;
 }
@@ -207,6 +209,7 @@ - (UITableView *)tableView
   if (_tableView == nil) {
     UITableViewStyle style = [TiUtils intValue:[self.proxy valueForKey:@"style"] def:UITableViewStylePlain];
     BOOL requiresEditingToMove = [TiUtils boolValue:[self.proxy valueForKey:@"requiresEditingToMove"] def:YES];
+    forceUpdates = [TiUtils boolValue:[self.proxy valueForKey:@"forceUpdates"] def:NO];
 
     _tableView = [[UITableView alloc] initWithFrame:self.bounds style:style];
     _tableView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
@@ -2002,6 +2005,7 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
         NSArray *indexPaths = [[self tableView] indexPathsForVisibleRows];
         NSMutableDictionary *eventArgs = [NSMutableDictionary dictionary];
         TiUIListSectionProxy *section;
+        CGFloat topSpacing = scrollView.contentOffset.y + scrollView.adjustedContentInset.top;
 
         if ([indexPaths count] > 0) {
           NSIndexPath *indexPath = [self pathForSearchPath:[indexPaths objectAtIndex:0]];
@@ -2013,9 +2017,10 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
           [eventArgs setValue:NUMINTEGER([indexPath section]) forKey:@"firstVisibleSectionIndex"];
           [eventArgs setValue:section forKey:@"firstVisibleSection"];
           [eventArgs setValue:[section itemAtIndex:[indexPath row]] forKey:@"firstVisibleItem"];
+          [eventArgs setValue:NUMINTEGER(topSpacing) forKey:@"top"];
 
-          if (lastVisibleItem != [indexPath row] || lastVisibleSection != [indexPath section]) {
-            // only log if the item changes
+          if (lastVisibleItem != [indexPath row] || lastVisibleSection != [indexPath section] || forceUpdates) {
+            // only log if the item changes or forced
             [self.proxy fireEvent:@"scrolling" withObject:eventArgs propagate:NO];
             lastVisibleItem = [indexPath row];
             lastVisibleSection = [indexPath section];
@@ -2028,6 +2033,7 @@ - (void)scrollViewDidScroll:(UIScrollView *)scrollView
           [eventArgs setValue:NUMINTEGER(0) forKey:@"firstVisibleSectionIndex"];
           [eventArgs setValue:section forKey:@"firstVisibleSection"];
           [eventArgs setValue:NUMINTEGER(-1) forKey:@"firstVisibleItem"];
+          [eventArgs setValue:NUMINTEGER(topSpacing) forKey:@"top"];
         }
       });
     }