Merge pull request boostcampwm-2022#163 from eoeo0326/feat/search_com…

…pose_paging

검색 Compose Paging 적용

app/src/main/AndroidManifest.xml

@@ -34,10 +34,6 @@
         </activity>
         <activity
             android:name=".presentation.searchfilm.SearchFilmComposeActivity"
-            android:exported="false"
-            android:theme="@style/Theme.DailyFilm" />
-        <activity
-            android:name=".presentation.searchfilm.SearchFilmActivity"
             android:exported="false" />
         <activity
             android:name=".presentation.settings.SettingsActivity"

app/src/main/java/com/boostcamp/dailyfilm/data/calendar/CalendarDao.kt

@@ -11,16 +11,23 @@ import kotlinx.coroutines.flow.Flow
 interface CalendarDao {
     @Query(
         "SELECT * FROM film_entity " +
-            "WHERE updateDate BETWEEN :startAt AND :endAt "
+            "WHERE updateDate BETWEEN :startAt AND :endAt ",
     )
     fun loadFilmFlow(startAt: Int, endAt: Int): Flow<List<FilmEntity?>>
 
     @Query(
         "SELECT * FROM film_entity " +
-            "WHERE updateDate BETWEEN :startAt AND :endAt "
+            "WHERE updateDate BETWEEN :startAt AND :endAt ",
     )
     suspend fun loadFilm(startAt: Int, endAt: Int): List<FilmEntity?>
 
+    @Query(
+        "SELECT * FROM film_entity " +
+            "WHERE updateDate BETWEEN :startAt AND :endAt " +
+            "ORDER BY updateDate ASC LIMIT :count OFFSET :page",
+    )
+    suspend fun loadPagedFilm(startAt: Int, endAt: Int, page: Int, count: Int = 10): List<FilmEntity?>
+
     @Insert(onConflict = OnConflictStrategy.REPLACE)
     suspend fun insertAll(filmEntityList: List<FilmEntity?>)
 

app/src/main/java/com/boostcamp/dailyfilm/data/calendar/CalendarDataSource.kt

@@ -14,6 +14,8 @@ interface CalendarDataSource {
 
     suspend fun loadFilm(startAt: Int, endAt: Int): List<FilmEntity?>
 
+    suspend fun loadPagedFilm(startAt: Int, endAt: Int, page: Int): List<FilmEntity?>
+
     suspend fun insertFilm(film: FilmEntity)
 
     suspend fun insertAllFilm(filmList: List<FilmEntity>)
@@ -22,7 +24,7 @@ interface CalendarDataSource {
 }
 
 class CalendarLocalDataSource(
-    private val calendarDao: CalendarDao
+    private val calendarDao: CalendarDao,
 ) : CalendarDataSource {
 
     override fun loadFilmFlow(startAt: Int, endAt: Int): Flow<List<FilmEntity?>> =
@@ -31,6 +33,9 @@ class CalendarLocalDataSource(
     override suspend fun loadFilm(startAt: Int, endAt: Int): List<FilmEntity?> =
         calendarDao.loadFilm(startAt, endAt)
 
+    override suspend fun loadPagedFilm(startAt: Int, endAt: Int, page: Int): List<FilmEntity?> =
+        calendarDao.loadPagedFilm(startAt, endAt, page)
+
     override suspend fun insertFilm(film: FilmEntity) {
         calendarDao.insert(film)
     }

app/src/main/java/com/boostcamp/dailyfilm/data/calendar/CalendarPagingSource.kt

@@ -0,0 +1,39 @@
+package com.boostcamp.dailyfilm.data.calendar
+
+import androidx.paging.PagingSource
+import androidx.paging.PagingState
+import com.boostcamp.dailyfilm.data.model.DailyFilmItem
+
+class CalendarPagingSource(
+    private val startAt: Int,
+    private val endAt: Int,
+    private val calendarDataSource: CalendarDataSource,
+) : PagingSource<Int, DailyFilmItem>() {
+    override suspend fun load(params: LoadParams<Int>): LoadResult<Int, DailyFilmItem> {
+        runCatching {
+            val page = params.key ?: 0
+            val data = calendarDataSource.loadPagedFilm(startAt, endAt, page).filterNotNull().map { it.mapToDailyFilmItem() }
+            return LoadResult.Page(
+                data = data,
+                prevKey = if (page == 0) null else shouldPositive(page - PAGING_SIZE),
+                nextKey = if (data.isEmpty()) null else page + data.size,
+            )
+        }.onFailure {
+            return LoadResult.Error(it)
+        }
+        return LoadResult.Error(Exception("Unknown Error in CalendarPagingSource"))
+    }
+
+    override fun getRefreshKey(state: PagingState<Int, DailyFilmItem>): Int? {
+        return state.anchorPosition?.let { anchorPosition ->
+            state.closestPageToPosition(anchorPosition)?.prevKey?.plus(PAGING_SIZE)
+                ?: state.closestPageToPosition(anchorPosition)?.nextKey?.minus(PAGING_SIZE)
+        }
+    }
+
+    private fun shouldPositive(num: Int) = if (num < 0) 0 else num
+
+    companion object {
+        const val PAGING_SIZE = 10
+    }
+}

app/src/main/java/com/boostcamp/dailyfilm/data/calendar/CalendarRepository.kt

@@ -1,5 +1,9 @@
 package com.boostcamp.dailyfilm.data.calendar
 
+import androidx.paging.Pager
+import androidx.paging.PagingConfig
+import androidx.paging.PagingData
+import com.boostcamp.dailyfilm.data.calendar.CalendarPagingSource.Companion.PAGING_SIZE
 import com.boostcamp.dailyfilm.data.model.DailyFilmItem
 import com.boostcamp.dailyfilm.data.model.Result
 import kotlinx.coroutines.flow.Flow
@@ -10,11 +14,13 @@ interface CalendarRepository {
 
     suspend fun loadFilm(startAt: String, endAt: String): List<DailyFilmItem?>
 
+    suspend fun loadPagedFilm(startAt: String, endAt: String): Flow<PagingData<DailyFilmItem>>
+
     suspend fun deleteAllData(): Result<Unit>
 }
 
 class CalendarRepositoryImpl(
-    private val calendarLocalDataSource: CalendarDataSource
+    private val calendarLocalDataSource: CalendarDataSource,
 ) : CalendarRepository {
 
     override fun loadFilmInfo(startAt: String, endAt: String): Flow<List<DailyFilmItem?>> =
@@ -29,6 +35,11 @@ class CalendarRepositoryImpl(
             filmEntity?.mapToDailyFilmItem()
         }
 
+    override suspend fun loadPagedFilm(startAt: String, endAt: String): Flow<PagingData<DailyFilmItem>> =
+        Pager(config = PagingConfig(pageSize = PAGING_SIZE)) {
+            CalendarPagingSource(startAt.toInt(), endAt.toInt(), calendarLocalDataSource)
+        }.flow
+
     override suspend fun deleteAllData(): Result<Unit> =
         calendarLocalDataSource.deleteAllData()
 }