From 63f460b7cb3404146ff76f1658075a0cc8f84dff Mon Sep 17 00:00:00 2001
From: zhye <zhye90@gmail.com>
Date: Mon, 28 Feb 2022 23:56:40 +0900
Subject: [PATCH] Fix paging source key

---
 .../codelabs/paging/data/GithubPagingSource.kt        | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/app/src/main/java/com/example/android/codelabs/paging/data/GithubPagingSource.kt b/app/src/main/java/com/example/android/codelabs/paging/data/GithubPagingSource.kt
index 890cdba4..16b7ccb2 100644
--- a/app/src/main/java/com/example/android/codelabs/paging/data/GithubPagingSource.kt
+++ b/app/src/main/java/com/example/android/codelabs/paging/data/GithubPagingSource.kt
@@ -33,11 +33,18 @@ class GithubPagingSource(
     private val query: String
 ) : PagingSource<Int, Repo>() {
     override suspend fun load(params: LoadParams<Int>): LoadResult<Int, Repo> {
-        val position = params.key ?: GITHUB_STARTING_PAGE_INDEX
+        val position = params.key?.let {
+            it * NETWORK_PAGE_SIZE / params.loadSize
+        } ?: GITHUB_STARTING_PAGE_INDEX
         val apiQuery = query + IN_QUALIFIER
         return try {
             val response = service.searchRepos(apiQuery, position, params.loadSize)
             val repos = response.items
+            val prevKey = if (position == GITHUB_STARTING_PAGE_INDEX) {
+                null
+            } else {
+                (position * params.loadSize / NETWORK_PAGE_SIZE) - 1
+            }
             val nextKey = if (repos.isEmpty()) {
                 null
             } else {
@@ -47,7 +54,7 @@ class GithubPagingSource(
             }
             LoadResult.Page(
                 data = repos,
-                prevKey = if (position == GITHUB_STARTING_PAGE_INDEX) null else position - 1,
+                prevKey = prevKey,
                 nextKey = nextKey
             )
         } catch (exception: IOException) {