Pre fetch next page

Automattic · Mar 10, 2023 · 0fd13a5 · 0fd13a5
1 parent 59b4879
commit 0fd13a5
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Showing 2 changed files with 12 additions and 2 deletions.
diff --git a/...rc/main/java/au/com/shiftyjelly/pocketcasts/discover/util/ScrollingLinearLayoutManager.kt b/...rc/main/java/au/com/shiftyjelly/pocketcasts/discover/util/ScrollingLinearLayoutManager.kt
@@ -6,7 +6,10 @@ import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.LinearSmoothScroller
 import androidx.recyclerview.widget.RecyclerView
 
-/* Increases scrolling speed of recyclerView.smoothScrollToPosition(position) */
+/*
+1. Increases scrolling speed of recyclerView.smoothScrollToPosition(position)
+2. Sets custom extra layout space for pre caching an extra page
+*/
 class ScrollingLinearLayoutManager(
     context: Context?,
     orientation: Int,
@@ -27,6 +30,13 @@ class ScrollingLinearLayoutManager(
         startSmoothScroll(linearSmoothScroller)
     }
 
+    /* By default, LinearLayoutManager lays out 1 extra page of items while smooth scrolling, in the direction of the scroll.
+       This behavior is overridden to lay out an extra page even on a manual swipe. */
+    override fun calculateExtraLayoutSpace(state: RecyclerView.State, extraLayoutSpace: IntArray) {
+        extraLayoutSpace[0] = 0
+        extraLayoutSpace[1] = this.width
+    }
+
     companion object {
         private const val MILLISECONDS_PER_INCH = 100f // default is 25f (bigger = slower)
     }

diff --git a/...es/discover/src/main/java/au/com/shiftyjelly/pocketcasts/discover/view/DiscoverAdapter.kt b/...es/discover/src/main/java/au/com/shiftyjelly/pocketcasts/discover/view/DiscoverAdapter.kt
@@ -79,7 +79,7 @@ import au.com.shiftyjelly.pocketcasts.ui.R as UR
 private const val MAX_ROWS_SMALL_LIST = 20
 private const val CURRENT_PAGE = "current_page"
 private const val TOTAL_PAGES = "total_pages"
-private const val INITIAL_PREFETCH_COUNT = 3
+private const val INITIAL_PREFETCH_COUNT = 1
 
 internal data class ChangeRegionRow(val region: DiscoverRegion)