更改目录结构

app/src/main/java/com/aiosman/riderpro/data/ListContainer.kt

@@ -0,0 +1,9 @@
+package com.aiosman.riderpro.data
+
+
+data class ListContainer<T>(
+    val total: Int,
+    val page: Int,
+    val pageSize: Int,
+    val list: List<T>
+)

app/src/main/java/com/aiosman/riderpro/data/moment/MomentPagingSource.kt

@@ -0,0 +1,92 @@
+package com.aiosman.riderpro.data.moment
+
+import android.net.http.HttpException
+import androidx.paging.PagingSource
+import androidx.paging.PagingState
+import com.aiosman.riderpro.R
+import com.aiosman.riderpro.data.ListContainer
+import com.aiosman.riderpro.model.MomentItem
+import java.io.IOException
+
+class MomentPagingSource(
+    private val remoteDataSource: MomentRemoteDataSource,
+) : PagingSource<Int, MomentItem>() {
+
+    override suspend fun load(params: LoadParams<Int>): LoadResult<Int, MomentItem> {
+        return try {
+            val currentPage = params.key ?: 1
+            val moments = remoteDataSource.getMoments(
+                pageNumber = currentPage
+            )
+
+            LoadResult.Page(
+                data = moments.list,
+                prevKey = if (currentPage == 1) null else currentPage - 1,
+                nextKey = if (moments.list.isEmpty()) null else moments.page + 1
+            )
+        } catch (exception: IOException) {
+            return LoadResult.Error(exception)
+        }
+    }
+
+    override fun getRefreshKey(state: PagingState<Int, MomentItem>): Int? {
+        return state.anchorPosition
+    }
+
+}
+
+class MomentRemoteDataSource(
+    private val momentService: MomentService,
+) {
+    suspend fun getMoments(pageNumber: Int): ListContainer<MomentItem> {
+        return momentService.getMoments(pageNumber)
+    }
+}
+
+interface MomentService {
+    suspend fun getMoments(pageNumber: Int): ListContainer<MomentItem>
+}
+
+class TestMomentServiceImpl() : MomentService {
+    val mockData = (0..300).toList().mapIndexed { idx, _ ->
+        MomentItem(
+            id = idx,
+            avatar = R.drawable.default_avatar,
+            nickname = "Onyama Limba",
+            location = "Japan",
+            time = "2023.02.02 11:23",
+            followStatus = false,
+            momentTextContent = "By strongarming Ducati into giving him the factory seat.Marquez effectively …",
+            momentPicture = R.drawable.default_moment_img,
+            likeCount = 21,
+            commentCount = 43,
+            shareCount = 33,
+            favoriteCount = 211
+        )
+    }
+    val testMomentBackend = TestMomentBackend(mockData)
+    override suspend fun getMoments(pageNumber: Int): ListContainer<MomentItem> {
+        return testMomentBackend.fetchMomentItems(pageNumber)
+    }
+}
+
+class TestMomentBackend(
+    private val mockData: List<MomentItem>,
+    private val loadDelay: Long = 500,
+) {
+    val DataBatchSize = 5
+    suspend fun fetchMomentItems(pageNumber: Int): ListContainer<MomentItem> {
+        val from = pageNumber * DataBatchSize
+        val to = (pageNumber + 1) * DataBatchSize
+        val currentSublist = mockData.subList(from, to)
+        // delay
+        kotlinx.coroutines.delay(loadDelay)
+        return ListContainer(
+            total = mockData.size,
+            page = pageNumber,
+            pageSize = DataBatchSize,
+            list = currentSublist
+        )
+    }
+
+}