fix: fix generating load trigger notification when itemCount is less than prefetchIndex.

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## Upcoming
 
+- [[#7](https://github.com/xsahil03x/super_paging/issues/7)] Fix generating load trigger notification when `itemCount` is less than `prefetchIndex`.
 - Added support for the `Pager.refresh` method to accept an optional `refreshKey` parameter.
 
 ## 0.1.0

lib/src/widget/bidirectional_paging_list_view.dart

@@ -463,24 +463,31 @@ class _BidirectionalPagingListViewState<Key, Value>
   }) {
     final items = pages.items;
     final itemCount = items.length;
-    final fetchIndex = pager.config.prefetchIndex;
+    final prefetchIndex = pager.config.prefetchIndex;
 
     // Helper function to generate prepend and append load trigger notifications
     void generatePrependAppendLoadTriggerNotification(int index) {
       // If there is no prefetch index, we don't need to generate any
       // notifications.
-      if (fetchIndex == null) return;
-
-      // Check if the index corresponds to near the top or bottom based on the
-      // 'reverse' flag.
-      final nearTop =
-          reverse ? index == itemCount - fetchIndex : index == fetchIndex;
-      final nearBottom =
-          reverse ? index == fetchIndex : index == itemCount - fetchIndex;
+      if (prefetchIndex == null) return;
+
+      // Generate notifications at the beginning and end of the list if the
+      // [itemCount] is less than [prefetchIndex].
+      if (prefetchIndex > itemCount) {
+        if (index == 0) onBuildingPrependLoadTriggerItem?.call();
+        if (index == itemCount - 1) onBuildingAppendLoadTriggerItem?.call();
+        return;
+      }
+
+      // Check if the index corresponds to near the top or bottom of the list
+      // based on the [reverse] flag.
+      final (nearTop, nearBottom) = switch (reverse) {
+        true => (index == itemCount - prefetchIndex, index == prefetchIndex),
+        false => (index == prefetchIndex, index == itemCount - prefetchIndex),
+      };
 
-      // Generate prepend notification.
+      // Generate notifications.
       if (nearTop) onBuildingPrependLoadTriggerItem?.call();
-      // Generate append notification.
       if (nearBottom) onBuildingAppendLoadTriggerItem?.call();
     }
 

lib/src/widget/paging_sliver_list.dart

@@ -265,20 +265,29 @@ class _PagingSliverListState<Key, Value>
     final itemCount = items.length;
     final prefetchIndex = pager.config.prefetchIndex;
 
+    // Helper function to generate prepend and append load trigger notifications
     void generatePrependAppendLoadTriggerNotification(int index) {
       // If there is no prefetch index, we don't have to generate any
       // notification.
       if (prefetchIndex == null) return;
 
-      // Generate prepend notification.
-      if (index == prefetchIndex) {
-        onBuildingPrependLoadTriggerItem?.call();
+      // Generate notifications at the beginning and end of the list if the
+      // [itemCount] is less than [prefetchIndex].
+      if (prefetchIndex > itemCount) {
+        if (index == 0) onBuildingPrependLoadTriggerItem?.call();
+        if (index == itemCount - 1) onBuildingAppendLoadTriggerItem?.call();
+        return;
       }
 
-      // Generate append notification.
-      if (index == itemCount - prefetchIndex) {
-        onBuildingAppendLoadTriggerItem?.call();
-      }
+      // Check if the index corresponds to near the top or bottom of the list.
+      final (nearTop, nearBottom) = (
+        index == prefetchIndex,
+        index == itemCount - prefetchIndex,
+      );
+
+      // Generate notifications.
+      if (nearTop) onBuildingPrependLoadTriggerItem?.call();
+      if (nearBottom) onBuildingAppendLoadTriggerItem?.call();
     }
 
     final itemBuilder = widget.itemBuilder;