├── app ├── .gitignore ├── src │ ├── main │ │ ├── res │ │ │ ├── values │ │ │ │ ├── strings.xml │ │ │ │ ├── colors.xml │ │ │ │ └── themes.xml │ │ │ ├── mipmap-hdpi │ │ │ │ ├── ic_launcher.webp │ │ │ │ └── ic_launcher_round.webp │ │ │ ├── mipmap-mdpi │ │ │ │ ├── ic_launcher.webp │ │ │ │ └── ic_launcher_round.webp │ │ │ ├── mipmap-xhdpi │ │ │ │ ├── ic_launcher.webp │ │ │ │ └── ic_launcher_round.webp │ │ │ ├── mipmap-xxhdpi │ │ │ │ ├── ic_launcher.webp │ │ │ │ └── ic_launcher_round.webp │ │ │ ├── mipmap-xxxhdpi │ │ │ │ ├── ic_launcher.webp │ │ │ │ └── ic_launcher_round.webp │ │ │ ├── mipmap-anydpi-v26 │ │ │ │ ├── ic_launcher.xml │ │ │ │ └── ic_launcher_round.xml │ │ │ ├── layout │ │ │ │ ├── load_state_view.xml │ │ │ │ ├── item.xml │ │ │ │ └── activity_main.xml │ │ │ ├── values-night │ │ │ │ └── themes.xml │ │ │ ├── drawable-v24 │ │ │ │ └── ic_launcher_foreground.xml │ │ │ └── drawable │ │ │ │ └── ic_launcher_background.xml │ │ ├── java │ │ │ └── com │ │ │ │ └── example │ │ │ │ └── paginationdemo │ │ │ │ ├── model │ │ │ │ └── Item.kt │ │ │ │ ├── db │ │ │ │ ├── ItemDao.kt │ │ │ │ └── ItemDatabase.kt │ │ │ │ ├── pagination │ │ │ │ ├── MainLoadStateAdapter.kt │ │ │ │ └── MainPagingSource.kt │ │ │ │ ├── MainViewModel.kt │ │ │ │ ├── MainAdapter.kt │ │ │ │ └── MainActivity.kt │ │ └── AndroidManifest.xml │ ├── test │ │ └── java │ │ │ └── com │ │ │ └── example │ │ │ └── paginationdemo │ │ │ └── ExampleUnitTest.kt │ └── androidTest │ │ └── java │ │ └── com │ │ └── example │ │ └── paginationdemo │ │ └── ExampleInstrumentedTest.kt ├── proguard-rules.pro └── build.gradle ├── gradle └── wrapper │ ├── gradle-wrapper.jar │ └── gradle-wrapper.properties ├── .gitignore ├── settings.gradle ├── LICENSE ├── gradle.properties ├── README.md ├── gradlew.bat └── gradlew /app/.gitignore: -------------------------------------------------------------------------------- 1 | /build -------------------------------------------------------------------------------- /app/src/main/res/values/strings.xml: -------------------------------------------------------------------------------- 1 | 2 | DBPagingDemo 3 | -------------------------------------------------------------------------------- /gradle/wrapper/gradle-wrapper.jar: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/gradle/wrapper/gradle-wrapper.jar -------------------------------------------------------------------------------- /app/src/main/res/mipmap-hdpi/ic_launcher.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-hdpi/ic_launcher.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-mdpi/ic_launcher.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-mdpi/ic_launcher.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xhdpi/ic_launcher.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xhdpi/ic_launcher.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xxhdpi/ic_launcher.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xxhdpi/ic_launcher.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | *.iml 2 | .gradle 3 | /local.properties 4 | .idea/ 5 | .DS_Store 6 | /build 7 | /captures 8 | .externalNativeBuild 9 | .cxx 10 | local.properties 11 | -------------------------------------------------------------------------------- /app/src/main/res/mipmap-hdpi/ic_launcher_round.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-hdpi/ic_launcher_round.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-mdpi/ic_launcher_round.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-mdpi/ic_launcher_round.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp -------------------------------------------------------------------------------- /app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/gouravkhunger/room-paging3-demo/HEAD/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp -------------------------------------------------------------------------------- /gradle/wrapper/gradle-wrapper.properties: -------------------------------------------------------------------------------- 1 | #Sun Apr 24 18:36:17 IST 2022 2 | distributionBase=GRADLE_USER_HOME 3 | distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip 4 | distributionPath=wrapper/dists 5 | zipStorePath=wrapper/dists 6 | zipStoreBase=GRADLE_USER_HOME 7 | -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/model/Item.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo.model 2 | 3 | import androidx.room.Entity 4 | import androidx.room.PrimaryKey 5 | 6 | @Entity(tableName = "items") 7 | data class Item( 8 | @PrimaryKey(autoGenerate = true) 9 | val id: Int = 0, 10 | val name: String 11 | ) -------------------------------------------------------------------------------- /app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /settings.gradle: -------------------------------------------------------------------------------- 1 | pluginManagement { 2 | repositories { 3 | gradlePluginPortal() 4 | google() 5 | mavenCentral() 6 | } 7 | } 8 | dependencyResolutionManagement { 9 | repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS) 10 | repositories { 11 | google() 12 | mavenCentral() 13 | } 14 | } 15 | rootProject.name = "DBPagingDemo" 16 | include ':app' 17 | -------------------------------------------------------------------------------- /app/src/main/res/values/colors.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | #FFBB86FC 4 | #FF6200EE 5 | #FF3700B3 6 | #FF03DAC5 7 | #FF018786 8 | #FF000000 9 | #FFFFFFFF 10 | -------------------------------------------------------------------------------- /app/src/test/java/com/example/paginationdemo/ExampleUnitTest.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo 2 | 3 | import org.junit.Test 4 | 5 | import org.junit.Assert.* 6 | 7 | /** 8 | * Example local unit test, which will execute on the development machine (host). 9 | * 10 | * See [testing documentation](http://d.android.com/tools/testing). 11 | */ 12 | class ExampleUnitTest { 13 | @Test 14 | fun addition_isCorrect() { 15 | assertEquals(4, 2 + 2) 16 | } 17 | } -------------------------------------------------------------------------------- /app/src/main/res/layout/load_state_view.xml: -------------------------------------------------------------------------------- 1 | 2 | 8 | 9 | 13 | 14 | -------------------------------------------------------------------------------- /app/src/main/res/layout/item.xml: -------------------------------------------------------------------------------- 1 | 2 | 8 | 9 | 14 | 15 | -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/db/ItemDao.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo.db 2 | 3 | import androidx.room.Dao 4 | import androidx.room.Insert 5 | import androidx.room.OnConflictStrategy 6 | import androidx.room.Query 7 | import com.example.paginationdemo.model.Item 8 | 9 | @Dao 10 | interface ItemDao { 11 | @Query("SELECT * FROM items ORDER BY id ASC LIMIT :limit OFFSET :offset") 12 | suspend fun getPagedList(limit: Int, offset: Int): List 13 | 14 | @Insert(onConflict = OnConflictStrategy.REPLACE) 15 | suspend fun insert(item: Item): Long 16 | } -------------------------------------------------------------------------------- /app/src/main/res/layout/activity_main.xml: -------------------------------------------------------------------------------- 1 | 2 | 8 | 9 | 14 | 15 | -------------------------------------------------------------------------------- /app/proguard-rules.pro: -------------------------------------------------------------------------------- 1 | # Add project specific ProGuard rules here. 2 | # You can control the set of applied configuration files using the 3 | # proguardFiles setting in build.gradle. 4 | # 5 | # For more details, see 6 | # http://developer.android.com/guide/developing/tools/proguard.html 7 | 8 | # If your project uses WebView with JS, uncomment the following 9 | # and specify the fully qualified class name to the JavaScript interface 10 | # class: 11 | #-keepclassmembers class fqcn.of.javascript.interface.for.webview { 12 | # public *; 13 | #} 14 | 15 | # Uncomment this to preserve the line number information for 16 | # debugging stack traces. 17 | #-keepattributes SourceFile,LineNumberTable 18 | 19 | # If you keep the line number information, uncomment this to 20 | # hide the original source file name. 21 | #-renamesourcefileattribute SourceFile -------------------------------------------------------------------------------- /app/src/androidTest/java/com/example/paginationdemo/ExampleInstrumentedTest.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo 2 | 3 | import androidx.test.platform.app.InstrumentationRegistry 4 | import androidx.test.ext.junit.runners.AndroidJUnit4 5 | 6 | import org.junit.Test 7 | import org.junit.runner.RunWith 8 | 9 | import org.junit.Assert.* 10 | 11 | /** 12 | * Instrumented test, which will execute on an Android device. 13 | * 14 | * See [testing documentation](http://d.android.com/tools/testing). 15 | */ 16 | @RunWith(AndroidJUnit4::class) 17 | class ExampleInstrumentedTest { 18 | @Test 19 | fun useAppContext() { 20 | // Context of the app under test. 21 | val appContext = InstrumentationRegistry.getInstrumentation().targetContext 22 | assertEquals("com.example.paginationdemo", appContext.packageName) 23 | } 24 | } -------------------------------------------------------------------------------- /app/src/main/AndroidManifest.xml: -------------------------------------------------------------------------------- 1 | 2 | 4 | 5 | 12 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | -------------------------------------------------------------------------------- /app/src/main/res/values/themes.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 16 | -------------------------------------------------------------------------------- /app/src/main/res/values-night/themes.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 16 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | MIT License 2 | 3 | Copyright (c) 2022 Gourav Khunger 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/pagination/MainLoadStateAdapter.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo.pagination 2 | 3 | import android.view.LayoutInflater 4 | import android.view.ViewGroup 5 | import androidx.core.view.isVisible 6 | import androidx.paging.LoadState 7 | import androidx.paging.LoadStateAdapter 8 | import androidx.recyclerview.widget.RecyclerView 9 | import com.example.paginationdemo.databinding.LoadStateViewBinding 10 | 11 | class MainLoadStateAdapter : LoadStateAdapter() { 12 | 13 | inner class LoadStateViewHolder(val binding: LoadStateViewBinding) : 14 | RecyclerView.ViewHolder(binding.root) 15 | 16 | override fun onCreateViewHolder(parent: ViewGroup, loadState: LoadState): LoadStateViewHolder { 17 | return LoadStateViewHolder( 18 | LoadStateViewBinding.inflate(LayoutInflater.from(parent.context), parent, false) 19 | ) 20 | } 21 | 22 | override fun onBindViewHolder(holder: LoadStateViewHolder, loadState: LoadState) { 23 | holder.binding.apply { 24 | progress.isVisible = loadState is LoadState.Loading 25 | } 26 | } 27 | } -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/MainViewModel.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo 2 | 3 | import androidx.lifecycle.ViewModel 4 | import androidx.lifecycle.ViewModelProvider 5 | import androidx.lifecycle.viewModelScope 6 | import androidx.paging.Pager 7 | import androidx.paging.PagingConfig 8 | import androidx.paging.cachedIn 9 | import com.example.paginationdemo.db.ItemDao 10 | import com.example.paginationdemo.pagination.MainPagingSource 11 | 12 | class MainViewModel( 13 | private val dao: ItemDao 14 | ): ViewModel() { 15 | 16 | val data = Pager( 17 | PagingConfig( 18 | pageSize = 20, 19 | enablePlaceholders = false, 20 | initialLoadSize = 20 21 | ), 22 | ) { 23 | MainPagingSource(dao) 24 | }.flow.cachedIn(viewModelScope) 25 | 26 | } 27 | 28 | class MainViewModelFactory( 29 | private val dao: ItemDao 30 | ) : ViewModelProvider.Factory { 31 | override fun create(modelClass: Class): T { 32 | if(modelClass.isAssignableFrom(MainViewModel::class.java)) { 33 | @Suppress("UNCHECKED_CAST") 34 | return MainViewModel(dao) as T 35 | } 36 | throw IllegalArgumentException("Unknown ViewModel class") 37 | } 38 | } -------------------------------------------------------------------------------- /gradle.properties: -------------------------------------------------------------------------------- 1 | # Project-wide Gradle settings. 2 | # IDE (e.g. Android Studio) users: 3 | # Gradle settings configured through the IDE *will override* 4 | # any settings specified in this file. 5 | # For more details on how to configure your build environment visit 6 | # http://www.gradle.org/docs/current/userguide/build_environment.html 7 | # Specifies the JVM arguments used for the daemon process. 8 | # The setting is particularly useful for tweaking memory settings. 9 | org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8 10 | # When configured, Gradle will run in incubating parallel mode. 11 | # This option should only be used with decoupled projects. More details, visit 12 | # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects 13 | # org.gradle.parallel=true 14 | # AndroidX package structure to make it clearer which packages are bundled with the 15 | # Android operating system, and which are packaged with your app"s APK 16 | # https://developer.android.com/topic/libraries/support-library/androidx-rn 17 | android.useAndroidX=true 18 | # Kotlin code style for this project: "official" or "obsolete": 19 | kotlin.code.style=official 20 | # Enables namespacing of each library's R class so that its R class includes only the 21 | # resources declared in the library itself and none from the library's dependencies, 22 | # thereby reducing the size of the R class for that library 23 | android.nonTransitiveRClass=true -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/pagination/MainPagingSource.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo.pagination 2 | 3 | import android.util.Log 4 | import androidx.paging.PagingSource 5 | import androidx.paging.PagingState 6 | import com.example.paginationdemo.db.ItemDao 7 | import com.example.paginationdemo.model.Item 8 | import kotlinx.coroutines.delay 9 | 10 | class MainPagingSource( 11 | private val dao: ItemDao 12 | ) : PagingSource() { 13 | override suspend fun load(params: LoadParams): LoadResult { 14 | val page = params.key ?: 0 15 | 16 | return try { 17 | Log.d("MainPagingSource", "load: $page") 18 | val entities = dao.getPagedList(params.loadSize, page * params.loadSize) 19 | if (page != 0) delay(1000) 20 | LoadResult.Page( 21 | data = entities, 22 | prevKey = if (page == 0) null else page - 1, 23 | nextKey = if (entities.isEmpty()) null else page + 1 24 | ) 25 | } catch (e: Exception) { 26 | LoadResult.Error(e) 27 | } 28 | } 29 | 30 | override fun getRefreshKey(state: PagingState): Int? { 31 | return state.anchorPosition?.let { anchorPosition -> 32 | val anchorPage = state.closestPageToPosition(anchorPosition) 33 | anchorPage?.prevKey?.plus(1) ?: anchorPage?.nextKey?.minus(1) 34 | } 35 | } 36 | } -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/MainAdapter.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo 2 | 3 | import android.view.LayoutInflater 4 | import android.view.ViewGroup 5 | import androidx.paging.PagingDataAdapter 6 | import androidx.recyclerview.widget.DiffUtil 7 | import androidx.recyclerview.widget.RecyclerView 8 | import com.example.paginationdemo.databinding.ItemBinding 9 | import com.example.paginationdemo.model.Item 10 | 11 | class MainAdapter : PagingDataAdapter(DIFF_CALLBACK) { 12 | 13 | companion object { 14 | val DIFF_CALLBACK = object : DiffUtil.ItemCallback() { 15 | override fun areItemsTheSame(oldItem: Item, newItem: Item): Boolean = 16 | oldItem.id == newItem.id 17 | 18 | override fun areContentsTheSame(oldItem: Item, newItem: Item): Boolean = 19 | oldItem == newItem 20 | } 21 | } 22 | 23 | inner class MainViewHolder(val binding: ItemBinding) : RecyclerView.ViewHolder(binding.root) 24 | 25 | override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MainViewHolder { 26 | return MainViewHolder( 27 | ItemBinding.inflate(LayoutInflater.from(parent.context), parent, false) 28 | ) 29 | } 30 | 31 | override fun onBindViewHolder(holder: MainViewHolder, position: Int) { 32 | val item = getItem(position) 33 | 34 | holder.binding.apply { 35 | textView.text = item?.name 36 | } 37 | } 38 | } -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/MainActivity.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo 2 | 3 | import androidx.appcompat.app.AppCompatActivity 4 | import android.os.Bundle 5 | import androidx.activity.viewModels 6 | import androidx.lifecycle.lifecycleScope 7 | import androidx.paging.LoadStateAdapter 8 | import com.example.paginationdemo.databinding.ActivityMainBinding 9 | import com.example.paginationdemo.db.ItemDao 10 | import com.example.paginationdemo.db.ItemDatabase 11 | import com.example.paginationdemo.pagination.MainLoadStateAdapter 12 | import kotlinx.coroutines.flow.collectLatest 13 | import kotlinx.coroutines.launch 14 | 15 | class MainActivity : AppCompatActivity() { 16 | 17 | private lateinit var binding: ActivityMainBinding 18 | private lateinit var dao: ItemDao 19 | private val viewModel: MainViewModel by viewModels { MainViewModelFactory(dao) } 20 | 21 | override fun onCreate(savedInstanceState: Bundle?) { 22 | super.onCreate(savedInstanceState) 23 | 24 | dao = ItemDatabase.getInstance(this).itemDao() 25 | 26 | binding = ActivityMainBinding.inflate(layoutInflater) 27 | setContentView(binding.root) 28 | 29 | val adapter = MainAdapter() 30 | binding.recyclerView.adapter = adapter.withLoadStateFooter( 31 | MainLoadStateAdapter() 32 | ) 33 | 34 | lifecycleScope.launch { 35 | viewModel.data.collectLatest { 36 | adapter.submitData(it) 37 | } 38 | } 39 | } 40 | } -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Demo Implementation of Paging 3 with Room DB 2 | 3 | [Read the article](https://genicsblog.com/gouravkhunger/pagination-in-android-room-database-using-the-paging-3-library). 4 | 5 | Demo implementation of Pagination in an Android Room Database using the Paging 3 Library. 6 | 7 | ## License 8 | 9 | This project is [`MIT`](https://github.com/gouravkhunger/room-paging3-demo/blob/main/LICENSE) Licensed. 10 | 11 | ``` 12 | MIT License 13 | 14 | Copyright (c) 2022 Gourav Khunger 15 | 16 | Permission is hereby granted, free of charge, to any person obtaining a copy 17 | of this software and associated documentation files (the "Software"), to deal 18 | in the Software without restriction, including without limitation the rights 19 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 20 | copies of the Software, and to permit persons to whom the Software is 21 | furnished to do so, subject to the following conditions: 22 | 23 | The above copyright notice and this permission notice shall be included in all 24 | copies or substantial portions of the Software. 25 | 26 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 27 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 28 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 29 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 30 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 31 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 32 | SOFTWARE. 33 | ``` 34 | -------------------------------------------------------------------------------- /app/build.gradle: -------------------------------------------------------------------------------- 1 | plugins { 2 | id 'com.android.application' 3 | id 'org.jetbrains.kotlin.android' 4 | id 'kotlin-kapt' 5 | } 6 | 7 | android { 8 | compileSdk 32 9 | 10 | defaultConfig { 11 | applicationId "com.example.paginationdemo" 12 | minSdk 23 13 | targetSdk 32 14 | versionCode 1 15 | versionName "1.0" 16 | 17 | testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner" 18 | } 19 | 20 | buildTypes { 21 | release { 22 | minifyEnabled false 23 | proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro' 24 | } 25 | } 26 | compileOptions { 27 | sourceCompatibility JavaVersion.VERSION_1_8 28 | targetCompatibility JavaVersion.VERSION_1_8 29 | } 30 | kotlinOptions { 31 | jvmTarget = '1.8' 32 | } 33 | viewBinding { 34 | enabled = true 35 | } 36 | } 37 | 38 | dependencies { 39 | 40 | implementation 'androidx.core:core-ktx:1.7.0' 41 | implementation 'androidx.appcompat:appcompat:1.4.1' 42 | implementation 'com.google.android.material:material:1.5.0' 43 | implementation 'androidx.constraintlayout:constraintlayout:2.1.3' 44 | testImplementation 'junit:junit:4.13.2' 45 | androidTestImplementation 'androidx.test.ext:junit:1.1.3' 46 | androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0' 47 | 48 | implementation "androidx.paging:paging-runtime:3.1.1" 49 | 50 | implementation "androidx.core:core-ktx:1.7.0" 51 | implementation 'androidx.activity:activity-ktx:1.4.0' 52 | 53 | implementation "androidx.room:room-ktx:2.4.2" 54 | kapt "androidx.room:room-compiler:2.4.2" 55 | } -------------------------------------------------------------------------------- /app/src/main/java/com/example/paginationdemo/db/ItemDatabase.kt: -------------------------------------------------------------------------------- 1 | package com.example.paginationdemo.db 2 | 3 | import android.content.Context 4 | import androidx.room.Database 5 | import androidx.room.Room 6 | import androidx.room.RoomDatabase 7 | import androidx.sqlite.db.SupportSQLiteDatabase 8 | import com.example.paginationdemo.model.Item 9 | import kotlinx.coroutines.CoroutineScope 10 | import kotlinx.coroutines.Dispatchers 11 | import kotlinx.coroutines.launch 12 | 13 | @Database(entities = [Item::class], version = 1, exportSchema = false) 14 | abstract class ItemDatabase : RoomDatabase() { 15 | abstract fun itemDao(): ItemDao 16 | 17 | companion object { 18 | private var INSTANCE: ItemDatabase? = null 19 | 20 | fun getInstance(context: Context): ItemDatabase { 21 | return INSTANCE ?: synchronized(this) { 22 | val instance = Room.databaseBuilder( 23 | context, 24 | ItemDatabase::class.java, 25 | "item_database" 26 | ).addCallback(object : RoomDatabase.Callback() { 27 | override fun onCreate(db: SupportSQLiteDatabase) { 28 | super.onCreate(db) 29 | 30 | INSTANCE?.let { database -> 31 | CoroutineScope(Dispatchers.IO).launch { 32 | (0..100).forEach { 33 | database.itemDao().insert( Item(0, "Item $it") ) 34 | } 35 | } 36 | } 37 | } 38 | }).build() 39 | 40 | INSTANCE = instance 41 | instance 42 | } 43 | } 44 | } 45 | } -------------------------------------------------------------------------------- /app/src/main/res/drawable-v24/ic_launcher_foreground.xml: -------------------------------------------------------------------------------- 1 | 7 | 8 | 9 | 15 | 18 | 21 | 22 | 23 | 24 | 30 | -------------------------------------------------------------------------------- /gradlew.bat: -------------------------------------------------------------------------------- 1 | @rem 2 | @rem Copyright 2015 the original author or authors. 3 | @rem 4 | @rem Licensed under the Apache License, Version 2.0 (the "License"); 5 | @rem you may not use this file except in compliance with the License. 6 | @rem You may obtain a copy of the License at 7 | @rem 8 | @rem https://www.apache.org/licenses/LICENSE-2.0 9 | @rem 10 | @rem Unless required by applicable law or agreed to in writing, software 11 | @rem distributed under the License is distributed on an "AS IS" BASIS, 12 | @rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | @rem See the License for the specific language governing permissions and 14 | @rem limitations under the License. 15 | @rem 16 | 17 | @if "%DEBUG%" == "" @echo off 18 | @rem ########################################################################## 19 | @rem 20 | @rem Gradle startup script for Windows 21 | @rem 22 | @rem ########################################################################## 23 | 24 | @rem Set local scope for the variables with windows NT shell 25 | if "%OS%"=="Windows_NT" setlocal 26 | 27 | set DIRNAME=%~dp0 28 | if "%DIRNAME%" == "" set DIRNAME=. 29 | set APP_BASE_NAME=%~n0 30 | set APP_HOME=%DIRNAME% 31 | 32 | @rem Resolve any "." and ".." in APP_HOME to make it shorter. 33 | for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi 34 | 35 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 36 | set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" 37 | 38 | @rem Find java.exe 39 | if defined JAVA_HOME goto findJavaFromJavaHome 40 | 41 | set JAVA_EXE=java.exe 42 | %JAVA_EXE% -version >NUL 2>&1 43 | if "%ERRORLEVEL%" == "0" goto execute 44 | 45 | echo. 46 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 47 | echo. 48 | echo Please set the JAVA_HOME variable in your environment to match the 49 | echo location of your Java installation. 50 | 51 | goto fail 52 | 53 | :findJavaFromJavaHome 54 | set JAVA_HOME=%JAVA_HOME:"=% 55 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe 56 | 57 | if exist "%JAVA_EXE%" goto execute 58 | 59 | echo. 60 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 61 | echo. 62 | echo Please set the JAVA_HOME variable in your environment to match the 63 | echo location of your Java installation. 64 | 65 | goto fail 66 | 67 | :execute 68 | @rem Setup the command line 69 | 70 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar 71 | 72 | 73 | @rem Execute Gradle 74 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %* 75 | 76 | :end 77 | @rem End local scope for the variables with windows NT shell 78 | if "%ERRORLEVEL%"=="0" goto mainEnd 79 | 80 | :fail 81 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of 82 | rem the _cmd.exe /c_ return code! 83 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 84 | exit /b 1 85 | 86 | :mainEnd 87 | if "%OS%"=="Windows_NT" endlocal 88 | 89 | :omega 90 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_launcher_background.xml: -------------------------------------------------------------------------------- 1 | 2 | 7 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 105 | 110 | 115 | 120 | 125 | 130 | 135 | 140 | 145 | 150 | 155 | 160 | 165 | 170 | 171 | -------------------------------------------------------------------------------- /gradlew: -------------------------------------------------------------------------------- 1 | #!/usr/bin/env sh 2 | 3 | # 4 | # Copyright 2015 the original author or authors. 5 | # 6 | # Licensed under the Apache License, Version 2.0 (the "License"); 7 | # you may not use this file except in compliance with the License. 8 | # You may obtain a copy of the License at 9 | # 10 | # https://www.apache.org/licenses/LICENSE-2.0 11 | # 12 | # Unless required by applicable law or agreed to in writing, software 13 | # distributed under the License is distributed on an "AS IS" BASIS, 14 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 | # See the License for the specific language governing permissions and 16 | # limitations under the License. 17 | # 18 | 19 | ############################################################################## 20 | ## 21 | ## Gradle start up script for UN*X 22 | ## 23 | ############################################################################## 24 | 25 | # Attempt to set APP_HOME 26 | # Resolve links: $0 may be a link 27 | PRG="$0" 28 | # Need this for relative symlinks. 29 | while [ -h "$PRG" ] ; do 30 | ls=`ls -ld "$PRG"` 31 | link=`expr "$ls" : '.*-> $.*$$'` 32 | if expr "$link" : '/.*' > /dev/null; then 33 | PRG="$link" 34 | else 35 | PRG=`dirname "$PRG"`"/$link" 36 | fi 37 | done 38 | SAVED="`pwd`" 39 | cd "`dirname \"$PRG\"`/" >/dev/null 40 | APP_HOME="`pwd -P`" 41 | cd "$SAVED" >/dev/null 42 | 43 | APP_NAME="Gradle" 44 | APP_BASE_NAME=`basename "$0"` 45 | 46 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 47 | DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' 48 | 49 | # Use the maximum available, or set MAX_FD != -1 to use that value. 50 | MAX_FD="maximum" 51 | 52 | warn () { 53 | echo "$*" 54 | } 55 | 56 | die () { 57 | echo 58 | echo "$*" 59 | echo 60 | exit 1 61 | } 62 | 63 | # OS specific support (must be 'true' or 'false'). 64 | cygwin=false 65 | msys=false 66 | darwin=false 67 | nonstop=false 68 | case "`uname`" in 69 | CYGWIN* ) 70 | cygwin=true 71 | ;; 72 | Darwin* ) 73 | darwin=true 74 | ;; 75 | MINGW* ) 76 | msys=true 77 | ;; 78 | NONSTOP* ) 79 | nonstop=true 80 | ;; 81 | esac 82 | 83 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar 84 | 85 | 86 | # Determine the Java command to use to start the JVM. 87 | if [ -n "$JAVA_HOME" ] ; then 88 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then 89 | # IBM's JDK on AIX uses strange locations for the executables 90 | JAVACMD="$JAVA_HOME/jre/sh/java" 91 | else 92 | JAVACMD="$JAVA_HOME/bin/java" 93 | fi 94 | if [ ! -x "$JAVACMD" ] ; then 95 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME 96 | 97 | Please set the JAVA_HOME variable in your environment to match the 98 | location of your Java installation." 99 | fi 100 | else 101 | JAVACMD="java" 102 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 103 | 104 | Please set the JAVA_HOME variable in your environment to match the 105 | location of your Java installation." 106 | fi 107 | 108 | # Increase the maximum file descriptors if we can. 109 | if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then 110 | MAX_FD_LIMIT=`ulimit -H -n` 111 | if [ $? -eq 0 ] ; then 112 | if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then 113 | MAX_FD="$MAX_FD_LIMIT" 114 | fi 115 | ulimit -n $MAX_FD 116 | if [ $? -ne 0 ] ; then 117 | warn "Could not set maximum file descriptor limit: $MAX_FD" 118 | fi 119 | else 120 | warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT" 121 | fi 122 | fi 123 | 124 | # For Darwin, add options to specify how the application appears in the dock 125 | if $darwin; then 126 | GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\"" 127 | fi 128 | 129 | # For Cygwin or MSYS, switch paths to Windows format before running java 130 | if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then 131 | APP_HOME=`cygpath --path --mixed "$APP_HOME"` 132 | CLASSPATH=`cygpath --path --mixed "$CLASSPATH"` 133 | 134 | JAVACMD=`cygpath --unix "$JAVACMD"` 135 | 136 | # We build the pattern for arguments to be converted via cygpath 137 | ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null` 138 | SEP="" 139 | for dir in $ROOTDIRSRAW ; do 140 | ROOTDIRS="$ROOTDIRS$SEP$dir" 141 | SEP="|" 142 | done 143 | OURCYGPATTERN="(^($ROOTDIRS))" 144 | # Add a user-defined pattern to the cygpath arguments 145 | if [ "$GRADLE_CYGPATTERN" != "" ] ; then 146 | OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)" 147 | fi 148 | # Now convert the arguments - kludge to limit ourselves to /bin/sh 149 | i=0 150 | for arg in "$@" ; do 151 | CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -` 152 | CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option 153 | 154 | if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition 155 | eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"` 156 | else 157 | eval `echo args$i`="\"$arg\"" 158 | fi 159 | i=`expr $i + 1` 160 | done 161 | case $i in 162 | 0) set -- ;; 163 | 1) set -- "$args0" ;; 164 | 2) set -- "$args0" "$args1" ;; 165 | 3) set -- "$args0" "$args1" "$args2" ;; 166 | 4) set -- "$args0" "$args1" "$args2" "$args3" ;; 167 | 5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;; 168 | 6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;; 169 | 7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;; 170 | 8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;; 171 | 9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;; 172 | esac 173 | fi 174 | 175 | # Escape application args 176 | save () { 177 | for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done 178 | echo " " 179 | } 180 | APP_ARGS=`save "$@"` 181 | 182 | # Collect all arguments for the java command, following the shell quoting and substitution rules 183 | eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS" 184 | 185 | exec "$JAVACMD" "$@" 186 | --------------------------------------------------------------------------------