feat: refreshVisibleItems

Author: farfromrefug

src/collectionview-common.ts

@@ -169,6 +169,7 @@ export abstract class CollectionViewBase extends View implements CollectionViewD
     }
 
     public abstract refresh();
+    public abstract refreshVisibleItems();
     public abstract scrollToIndex(index: number, animated: boolean);
     public onLayout(left: number, top: number, right: number, bottom: number) {
         super.onLayout(left, top, right, bottom);

src/collectionview.android.ts

@@ -709,6 +709,20 @@ export class CollectionView extends CollectionViewBase {
         this._listViewAdapter.notifyDataSetChanged();
     }
 
+    refreshVisibleItems() {
+        const view = this.nativeViewProtected;
+        if (!view) {
+            return;
+        }
+        const layoutManager = this.layoutManager as androidx.recyclerview.widget.LinearLayoutManager;
+        if (layoutManager['findFirstVisibleItemPosition']) {
+            const first = layoutManager.findFirstVisibleItemPosition();
+            const last = layoutManager.findLastVisibleItemPosition();
+            this._listViewAdapter.notifyItemRangeChanged(first, last - first);
+
+        }
+    }
+
     @profile
     public refresh() {
         if (!this.nativeViewProtected) {

src/collectionview.d.ts

@@ -7,6 +7,7 @@ export type Orientation = 'horizontal' | 'vertical';
 
 export class CollectionView extends CollectionViewBase {
     public refresh();
+    public refreshVisibleItems();
     public scrollToIndex(index: number, animated: boolean);
     public getViewForItemAtIndex(index: number): View;
     // on iOS a view is dragged from its center by default

src/collectionview.ios.ts

@@ -453,6 +453,21 @@ export class CollectionView extends CollectionViewBase {
             }
         }, this);
     }
+
+    refreshVisibleItems() {
+        const view = this.nativeViewProtected;
+        if (!view) {
+            return;
+        }
+        const visibles = view.indexPathsForVisibleItems;
+        UIView.performWithoutAnimation(()=>{
+            view.performBatchUpdatesCompletion(() => {
+                view.reloadItemsAtIndexPaths(visibles);
+            }, null);
+        });
+    }
+
+
     @profile
     public refresh() {
         if (!this.isLoaded || !this.nativeView) {