如何在PHP中使用Android Jetpack Paging 3

我已经成功地在我的应用程序中实现了Android分页库， 问题是-我不知道如何将它与我的PHP代码一起作为后端使用，比如要加载的项目数等

get_feed.php

<?php

$limit = 2;

//find out how many rows are in the table
$sql = "SELECT count(*) FROM uploads"; 
$result = $conn->prepare($sql); 
$result->execute();
$total = $result->fetchColumn();

//total pages
$totalpages = ceil($total/$limit);

//get the current page or set a default
if (isset($_GET['page']) && is_numeric($_GET['page'])) {
// cast var as int
(int) $currentpage =  $_GET['page'];
} else {
//default page num
$currentpage = 1;
}


//if current page is less than first page...
if ($currentpage < 1) {
// set current page to first page
$currentpage = 1;
} 

//the offset of the list, based on current page 
$offset = ($currentpage - 1) * $limit;

$stmt = "SELECT * FROM uploads ORDER by id DESC LIMIT $offset, $limit";

//I get all requiresd data, send and encode in json
echo json_encode($obj);

?>

FeedSource.kt

@GET(EndPoints.GET_RANDOM_FEED)
suspend fun getRandomFeed(
    @Query("page") page: Int
) : PostsResponse

class FeedSource(private val apiDataSource: ApiDataSource) : PagingSource<Int, Posts>() {

override suspend fun load(params: LoadParams<Int>): LoadResult<Int, Posts> {
    return try {
        //start from page 1 for undefined
        val nextPage = params.key ?: 1
        val response = apiDataSource.getRandomFeed(nextPage)
        LoadResult.Page(
            data = response.feeds,
            prevKey = if (nextPage == 1) null else nextPage - 1,
            nextKey =  nextPage.plus(1)
        )
    } catch (e: Exception){
        LoadResult.Error(e)
    }
 }
}

@Singleton
class FeedViewModel constructor(private val apiDataSource: ApiDataSource) : ViewModel() {

//I want to load 10 items at first
val feeds = Pager(PagingConfig(pageSize = 10)) {
    FeedSource(apiDataSource)
}.flow.cachedIn(viewModelScope)
}

实际上，所有项目都是一次加载的。我已经设置了loadState适配器，它应该只在项目加载或出错时显示微调器（视情况而定）。 但现在，微调器仅在加载所有项并抛出HTTP 429错误时显示

如何使应用程序最初加载10个项目，然后根据我的PHP代码一次加载2个项目