├── .gitignore ├── .idea ├── .name ├── codeStyles │ └── Project.xml ├── gradle.xml ├── jarRepositories.xml ├── misc.xml ├── runConfigurations.xml └── vcs.xml ├── app ├── .gitignore ├── build.gradle ├── proguard-rules.pro └── src │ └── main │ ├── AndroidManifest.xml │ ├── java │ └── com │ │ └── app │ │ └── holderprefetcher │ │ ├── CompanyAdapter.kt │ │ ├── MainActivity.kt │ │ ├── Model.kt │ │ ├── ViewHolderFactory.kt │ │ └── prefetcher │ │ ├── HolderPrefetcher.kt │ │ ├── PrefetchRecycledViewPool.kt │ │ ├── RecyclerViewProxy.kt │ │ └── ViewHolderCreator.kt │ └── res │ ├── drawable-v24 │ └── ic_launcher_foreground.xml │ ├── drawable │ ├── ic_amazon.xml │ ├── ic_apple.xml │ ├── ic_facebook.xml │ ├── ic_google.xml │ ├── ic_ibm.xml │ ├── ic_intel.xml │ ├── ic_launcher_background.xml │ ├── ic_microsoft.xml │ └── ic_qualcomm.xml │ ├── layout │ ├── activity_main.xml │ └── item_list.xml │ ├── mipmap-anydpi-v26 │ ├── ic_launcher.xml │ └── ic_launcher_round.xml │ ├── mipmap-hdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-mdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xxhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ ├── mipmap-xxxhdpi │ ├── ic_launcher.png │ └── ic_launcher_round.png │ └── values │ ├── colors.xml │ ├── strings.xml │ └── styles.xml ├── build.gradle ├── gradle.properties ├── gradle └── wrapper │ ├── gradle-wrapper.jar │ └── gradle-wrapper.properties ├── gradlew ├── gradlew.bat └── settings.gradle /.gitignore: -------------------------------------------------------------------------------- 1 | *.iml 2 | .gradle 3 | /local.properties 4 | /.idea/caches 5 | /.idea/libraries 6 | /.idea/modules.xml 7 | /.idea/workspace.xml 8 | /.idea/navEditor.xml 9 | /.idea/assetWizardSettings.xml 10 | .DS_Store 11 | /build 12 | /captures 13 | .externalNativeBuild 14 | .cxx 15 | -------------------------------------------------------------------------------- /.idea/.name: -------------------------------------------------------------------------------- 1 | Holder prefetcher -------------------------------------------------------------------------------- /.idea/codeStyles/Project.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 7 | 8 | 9 |
10 | 11 | 12 | 13 | xmlns:android 14 | 15 | ^$ 16 | 17 | 18 | 19 |
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112 | 113 | 114 | 115 | 116 | -------------------------------------------------------------------------------- /.idea/gradle.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 20 | 21 | -------------------------------------------------------------------------------- /.idea/jarRepositories.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 9 | 10 | 14 | 15 | 19 | 20 | 24 | 25 | -------------------------------------------------------------------------------- /.idea/misc.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 14 | -------------------------------------------------------------------------------- /.idea/runConfigurations.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 11 | 12 | -------------------------------------------------------------------------------- /.idea/vcs.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | -------------------------------------------------------------------------------- /app/.gitignore: -------------------------------------------------------------------------------- 1 | /build -------------------------------------------------------------------------------- /app/build.gradle: -------------------------------------------------------------------------------- 1 | apply plugin: 'com.android.application' 2 | apply plugin: 'kotlin-android' 3 | apply plugin: 'kotlin-android-extensions' 4 | 5 | android { 6 | compileSdkVersion 29 7 | buildToolsVersion "29.0.3" 8 | 9 | defaultConfig { 10 | applicationId "com.app.holderprefetcher" 11 | minSdkVersion 22 12 | targetSdkVersion 29 13 | versionCode 1 14 | versionName "1.0" 15 | 16 | testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner" 17 | } 18 | 19 | buildTypes { 20 | release { 21 | minifyEnabled false 22 | proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro' 23 | } 24 | } 25 | 26 | kotlinOptions { 27 | jvmTarget = '1.8' 28 | freeCompilerArgs = ["-XXLanguage:+InlineClasses"] 29 | } 30 | } 31 | 32 | dependencies { 33 | implementation fileTree(dir: "libs", include: ["*.jar"]) 34 | implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version" 35 | implementation 'androidx.core:core-ktx:1.3.0' 36 | implementation 'androidx.appcompat:appcompat:1.1.0' 37 | implementation 'androidx.constraintlayout:constraintlayout:1.1.3' 38 | implementation 'androidx.recyclerview:recyclerview:1.1.0' 39 | implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.8' 40 | implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.8' 41 | testImplementation 'junit:junit:4.12' 42 | androidTestImplementation 'androidx.test.ext:junit:1.1.1' 43 | androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0' 44 | 45 | } -------------------------------------------------------------------------------- /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/main/AndroidManifest.xml: -------------------------------------------------------------------------------- 1 | 2 | 4 | 5 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/CompanyAdapter.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher 2 | 3 | import android.view.ViewGroup 4 | import androidx.recyclerview.widget.RecyclerView 5 | import kotlin.coroutines.CoroutineContext 6 | 7 | class CompanyAdapter(private val items: List): RecyclerView.Adapter() { 8 | 9 | override fun getItemViewType(position: Int): Int { 10 | return (position / 20).coerceAtMost(7) 11 | } 12 | 13 | override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CompanyViewHolder { 14 | return ViewHolderFactory.createHolder(parent, viewType) 15 | } 16 | 17 | override fun getItemCount(): Int = items.size 18 | 19 | override fun onBindViewHolder(holder: CompanyViewHolder, position: Int) { 20 | holder.bind(items[position].someText) 21 | } 22 | } -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/MainActivity.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher 2 | 3 | import androidx.appcompat.app.AppCompatActivity 4 | import android.os.Bundle 5 | import androidx.recyclerview.widget.LinearLayoutManager 6 | import com.app.holderprefetcher.prefetcher.PrefetchRecycledViewPool 7 | import com.app.holderprefetcher.prefetcher.HolderPrefetcher 8 | import kotlinx.android.synthetic.main.activity_main.companyRecyclerView 9 | import kotlinx.coroutines.CoroutineScope 10 | import kotlinx.coroutines.Dispatchers 11 | import kotlinx.coroutines.ExperimentalCoroutinesApi 12 | import kotlinx.coroutines.SupervisorJob 13 | import kotlin.coroutines.CoroutineContext 14 | 15 | @ExperimentalCoroutinesApi 16 | class MainActivity : AppCompatActivity(), CoroutineScope { 17 | 18 | override val coroutineContext: CoroutineContext 19 | get() = Dispatchers.IO + SupervisorJob() 20 | 21 | private lateinit var viewPool: PrefetchRecycledViewPool 22 | 23 | override fun onCreate(savedInstanceState: Bundle?) { 24 | super.onCreate(savedInstanceState) 25 | setContentView(R.layout.activity_main) 26 | 27 | viewPool = PrefetchRecycledViewPool( 28 | this, 29 | this 30 | ).apply { 31 | prepare() 32 | } 33 | 34 | with(companyRecyclerView) { 35 | adapter = CompanyAdapter(Model.createList(800)) 36 | layoutManager = LinearLayoutManager(this@MainActivity) 37 | adapter?.notifyDataSetChanged() 38 | setRecycledViewPool(viewPool) 39 | } 40 | 41 | prefetchItems(viewPool) 42 | } 43 | 44 | private fun prefetchItems(holderPrefetcher: HolderPrefetcher) { 45 | val count = 20 46 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_GOOGLE, count) { fakeParent, viewType -> 47 | ViewHolderFactory.createHolder(fakeParent, viewType) 48 | } 49 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_FACEBOOK, count) { fakeParent, viewType -> 50 | ViewHolderFactory.createHolder(fakeParent, viewType) 51 | } 52 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_APPLE, count) { fakeParent, viewType -> 53 | ViewHolderFactory.createHolder(fakeParent, viewType) 54 | } 55 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_MICROSOFT, count) { fakeParent, viewType -> 56 | ViewHolderFactory.createHolder(fakeParent, viewType) 57 | } 58 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_AMAZON, count) { fakeParent, viewType -> 59 | ViewHolderFactory.createHolder(fakeParent, viewType) 60 | } 61 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_IBM, count) { fakeParent, viewType -> 62 | ViewHolderFactory.createHolder(fakeParent, viewType) 63 | } 64 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_INTEL, count) { fakeParent, viewType -> 65 | ViewHolderFactory.createHolder(fakeParent, viewType) 66 | } 67 | holderPrefetcher.setViewsCount(ViewHolderFactory.TYPE_QUALCOMM, count) { fakeParent, viewType -> 68 | ViewHolderFactory.createHolder(fakeParent, viewType) 69 | } 70 | } 71 | 72 | override fun onDestroy() { 73 | viewPool.clear() 74 | super.onDestroy() 75 | } 76 | } -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/Model.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher 2 | 3 | class Model(val someText: String) { 4 | 5 | companion object { 6 | fun createList(count: Int) : List { 7 | val result = mutableListOf() 8 | for (i in 0..count) { 9 | result.add(Model(i.toString())) 10 | } 11 | return result 12 | } 13 | } 14 | } -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/ViewHolderFactory.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher 2 | 3 | import android.graphics.drawable.Drawable 4 | import android.view.LayoutInflater 5 | import android.view.View 6 | import android.view.ViewGroup 7 | import android.widget.TextView 8 | import androidx.core.content.ContextCompat 9 | import androidx.recyclerview.widget.RecyclerView 10 | 11 | object ViewHolderFactory { 12 | 13 | const val TYPE_GOOGLE = 0 14 | const val TYPE_FACEBOOK = 1 15 | const val TYPE_APPLE = 2 16 | const val TYPE_MICROSOFT = 3 17 | const val TYPE_AMAZON = 4 18 | const val TYPE_IBM = 5 19 | const val TYPE_INTEL = 6 20 | const val TYPE_QUALCOMM = 7 21 | 22 | fun createHolder(parent: ViewGroup, viewType: Int) : CompanyViewHolder { 23 | val view = LayoutInflater.from(parent.context).inflate(R.layout.item_list, parent, false) 24 | Thread.sleep(30) // simulation of hard work 25 | return when (viewType) { 26 | TYPE_GOOGLE -> GoogleViewHolder(view) 27 | TYPE_FACEBOOK -> FacebookViewHolder(view) 28 | TYPE_APPLE -> AppleViewHolder(view) 29 | TYPE_MICROSOFT -> MicrosoftViewHolder(view) 30 | TYPE_AMAZON -> AmazonViewHolder(view) 31 | TYPE_IBM -> IbmViewHolder(view) 32 | TYPE_INTEL -> IntelViewHolder(view) 33 | TYPE_QUALCOMM -> QualcommViewHolder(view) 34 | else -> throw IllegalArgumentException("View type not found") 35 | } 36 | } 37 | } 38 | 39 | abstract class CompanyViewHolder(view: View) : RecyclerView.ViewHolder(view) { 40 | 41 | abstract val logo: Drawable? 42 | 43 | private val textView = view.findViewById(R.id.text) 44 | 45 | fun bind(text: String) { 46 | textView.text = text 47 | textView.setCompoundDrawablesWithIntrinsicBounds(logo, null, null, null) 48 | } 49 | } 50 | 51 | class GoogleViewHolder(view: View): CompanyViewHolder(view) { 52 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_google) 53 | } 54 | 55 | class FacebookViewHolder(view: View): CompanyViewHolder(view) { 56 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_facebook) 57 | } 58 | 59 | class AppleViewHolder(view: View): CompanyViewHolder(view) { 60 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_apple) 61 | } 62 | 63 | class MicrosoftViewHolder(view: View): CompanyViewHolder(view) { 64 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_microsoft) 65 | } 66 | 67 | class AmazonViewHolder(view: View): CompanyViewHolder(view) { 68 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_amazon) 69 | } 70 | 71 | class IbmViewHolder(view: View): CompanyViewHolder(view) { 72 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_ibm) 73 | } 74 | 75 | class IntelViewHolder(view: View): CompanyViewHolder(view) { 76 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_intel) 77 | } 78 | 79 | class QualcommViewHolder(view: View): CompanyViewHolder(view) { 80 | override val logo: Drawable? = ContextCompat.getDrawable(view.context, R.drawable.ic_qualcomm) 81 | } -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/prefetcher/HolderPrefetcher.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher.prefetcher 2 | 3 | import android.view.ViewGroup 4 | import androidx.recyclerview.widget.RecyclerView 5 | 6 | typealias HolderCreator = (fakeParent: ViewGroup, viewType: Int) -> RecyclerView.ViewHolder 7 | 8 | interface HolderPrefetcher { 9 | fun setViewsCount( 10 | viewType: Int, 11 | count: Int, 12 | holderCreator: HolderCreator 13 | ) 14 | } 15 | 16 | -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/prefetcher/PrefetchRecycledViewPool.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher.prefetcher 2 | 3 | import android.app.Activity 4 | import android.view.ViewGroup 5 | import androidx.recyclerview.widget.RecyclerView 6 | import androidx.recyclerview.widget.attachToPreventViewPoolFromClearing 7 | import androidx.recyclerview.widget.factorInCreateTime 8 | import androidx.recyclerview.widget.viewType 9 | import kotlinx.coroutines.CoroutineScope 10 | import kotlinx.coroutines.ExperimentalCoroutinesApi 11 | 12 | @ExperimentalCoroutinesApi 13 | class PrefetchRecycledViewPool(activity: Activity, coroutineScope: CoroutineScope) : RecyclerView.RecycledViewPool(), HolderPrefetcher { 14 | 15 | private val viewHolderCreator = ViewHolderCreator(activity, coroutineScope, ::putViewFromCreator) 16 | 17 | override fun setViewsCount(viewType: Int, count: Int, holderCreator: (fakeParent: ViewGroup, viewType: Int) -> RecyclerView.ViewHolder) { 18 | require(count > 0) 19 | viewHolderCreator.setPrefetchBound(holderCreator, viewType, count) 20 | } 21 | 22 | fun prepare() { 23 | viewHolderCreator.prepare() 24 | attachToPreventViewPoolFromClearing() 25 | } 26 | 27 | override fun putRecycledView(scrap: RecyclerView.ViewHolder) { 28 | val viewType = scrap.itemViewType 29 | setMaxRecycledViews(viewType, 20) 30 | super.putRecycledView(scrap) 31 | } 32 | 33 | override fun getRecycledView(viewType: Int): RecyclerView.ViewHolder? { 34 | val holder = super.getRecycledView(viewType) 35 | if (holder == null) { 36 | viewHolderCreator.itemCreatedOutside(viewType) 37 | } 38 | return holder 39 | } 40 | 41 | override fun clear() { 42 | viewHolderCreator.clear() 43 | super.clear() 44 | } 45 | 46 | private fun putViewFromCreator(scrap: RecyclerView.ViewHolder, creationTimeNs: Long) { 47 | factorInCreateTime(scrap.viewType, creationTimeNs) 48 | putRecycledView(scrap) 49 | } 50 | } -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/prefetcher/RecyclerViewProxy.kt: -------------------------------------------------------------------------------- 1 | @file:Suppress("PackageDirectoryMismatch") 2 | 3 | package androidx.recyclerview.widget 4 | 5 | import com.app.holderprefetcher.prefetcher.PrefetchRecycledViewPool 6 | import kotlinx.coroutines.ExperimentalCoroutinesApi 7 | 8 | internal fun RecyclerView.RecycledViewPool.attachToPreventViewPoolFromClearing() { 9 | this.attach() 10 | } 11 | 12 | @ExperimentalCoroutinesApi 13 | internal fun PrefetchRecycledViewPool.factorInCreateTime(viewType: Int, createTimeNs: Long) = (this as RecyclerView.RecycledViewPool).factorInCreateTime(viewType, createTimeNs) 14 | 15 | internal val ALLOW_THREAD_GAP_WORK = RecyclerView.ALLOW_THREAD_GAP_WORK 16 | 17 | internal var RecyclerView.ViewHolder.viewType: Int 18 | get() = itemViewType 19 | set(value) { 20 | mItemViewType = value 21 | } 22 | 23 | 24 | 25 | -------------------------------------------------------------------------------- /app/src/main/java/com/app/holderprefetcher/prefetcher/ViewHolderCreator.kt: -------------------------------------------------------------------------------- 1 | package com.app.holderprefetcher.prefetcher 2 | 3 | import android.app.Activity 4 | import android.util.SparseIntArray 5 | import android.widget.FrameLayout 6 | import androidx.recyclerview.widget.ALLOW_THREAD_GAP_WORK 7 | import androidx.recyclerview.widget.RecyclerView 8 | import androidx.recyclerview.widget.viewType 9 | import kotlinx.coroutines.CoroutineScope 10 | import kotlinx.coroutines.Dispatchers 11 | import kotlinx.coroutines.ExperimentalCoroutinesApi 12 | import kotlinx.coroutines.cancel 13 | import kotlinx.coroutines.channels.Channel 14 | import kotlinx.coroutines.channels.consumeEach 15 | import kotlinx.coroutines.launch 16 | import kotlinx.coroutines.withContext 17 | 18 | @ExperimentalCoroutinesApi 19 | internal class ViewHolderCreator( 20 | activity: Activity, 21 | private val coroutineScope: CoroutineScope, 22 | private val holderConsumer: (holder: RecyclerView.ViewHolder, creationTimeNs: Long) -> Unit 23 | ) { 24 | 25 | private val fakeParent by lazy { FrameLayout(activity) } 26 | private val createdOutsideChannel = Channel(1) 27 | private val enqueueChannel = Channel(1) 28 | private val createItemChannel = Channel(1) 29 | private val itemsCreated = SparseIntArray() 30 | private val itemsQueued = SparseIntArray() 31 | 32 | fun prepare() { 33 | coroutineScope.launch { 34 | createdOutsideChannel.consumeEach { 35 | createdOutside(it.viewType) 36 | } 37 | } 38 | 39 | coroutineScope.launch { 40 | enqueueChannel.consumeEach { 41 | enqueueBatch(it.holderCreator, it.viewType, it.itemsCount) 42 | } 43 | } 44 | 45 | coroutineScope.launch { 46 | createItemChannel.consumeEach { 47 | createItem(it.holderCreator, it.viewType) 48 | } 49 | } 50 | } 51 | 52 | fun clear() { 53 | clearAndCancel() 54 | coroutineScope.cancel() 55 | } 56 | 57 | fun setPrefetchBound(holderCreator: HolderCreator, viewType: Int, count: Int) { 58 | coroutineScope.launch { 59 | enqueueChannel.send(ViewHolderWrapper(holderCreator, viewType, count)) 60 | } 61 | } 62 | 63 | fun itemCreatedOutside(viewType: Int) { 64 | coroutineScope.launch { 65 | createdOutsideChannel.send(ViewType(viewType)) 66 | } 67 | } 68 | 69 | private fun createdOutside(viewType: Int) { 70 | itemsCreated.put(viewType, itemsCreated[viewType] + 1) 71 | } 72 | 73 | private fun enqueueBatch(holderCreator: HolderCreator, viewType: Int, count: Int) { 74 | if (itemsQueued[viewType] >= count) return 75 | itemsQueued.put(viewType, count) 76 | 77 | val created = itemsCreated[viewType] 78 | if (created >= count) return 79 | 80 | enqueueItemCreation(holderCreator, viewType) 81 | } 82 | 83 | private suspend fun createItem(holderCreator: HolderCreator, viewType: Int) { 84 | val created = itemsCreated[viewType] + 1 85 | val queued = itemsQueued[viewType] 86 | if (created > queued) return 87 | 88 | val holder: RecyclerView.ViewHolder 89 | val start: Long 90 | val end: Long 91 | 92 | try { 93 | start = nanoTimeIfNeed() 94 | holder = holderCreator(fakeParent, viewType) 95 | end = nanoTimeIfNeed() 96 | } catch (e: Exception) { 97 | return 98 | } 99 | 100 | holder.viewType = viewType 101 | itemsCreated.put(viewType, created) 102 | 103 | withContext(Dispatchers.Main) { 104 | holderConsumer(holder, end - start) 105 | } 106 | if (created < queued) enqueueItemCreation(holderCreator, viewType) 107 | } 108 | 109 | private fun enqueueItemCreation(holderCreator: HolderCreator, viewType: Int) { 110 | coroutineScope.launch { 111 | createItemChannel.send(ViewHolderWrapper(holderCreator, viewType)) 112 | } 113 | } 114 | 115 | private fun clearAndCancel() { 116 | createItemChannel.cancel() 117 | enqueueChannel.cancel() 118 | createdOutsideChannel.cancel() 119 | itemsQueued.clear() 120 | itemsCreated.clear() 121 | } 122 | 123 | private fun nanoTimeIfNeed() = if (ALLOW_THREAD_GAP_WORK) System.nanoTime() else 0L 124 | 125 | private class ViewHolderWrapper( 126 | val holderCreator: HolderCreator, 127 | val viewType: Int, 128 | val itemsCount: Int = 0 129 | ) 130 | } 131 | 132 | private inline class ViewType(val viewType: Int) 133 | -------------------------------------------------------------------------------- /app/src/main/res/drawable-v24/ic_launcher_foreground.xml: -------------------------------------------------------------------------------- 1 | 7 | 8 | 9 | 15 | 18 | 21 | 22 | 23 | 24 | 30 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_amazon.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | 6 | 7 | 8 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_apple.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_facebook.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | 6 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_google.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | 6 | 7 | 8 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_ibm.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_intel.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | 6 | -------------------------------------------------------------------------------- /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 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_microsoft.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /app/src/main/res/drawable/ic_qualcomm.xml: -------------------------------------------------------------------------------- 1 | 3 | 4 | 5 | -------------------------------------------------------------------------------- /app/src/main/res/layout/activity_main.xml: -------------------------------------------------------------------------------- 1 | 2 | 8 | 9 | 13 | -------------------------------------------------------------------------------- /app/src/main/res/layout/item_list.xml: -------------------------------------------------------------------------------- 1 | 2 | 5 | 6 | 11 | 12 | -------------------------------------------------------------------------------- /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 | 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/app/src/main/res/values/colors.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | #6200EE 4 | #3700B3 5 | #03DAC5 6 | -------------------------------------------------------------------------------- /app/src/main/res/values/strings.xml: -------------------------------------------------------------------------------- 1 | 2 | Holder prefetcher 3 | -------------------------------------------------------------------------------- /app/src/main/res/values/styles.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 9 | 10 | -------------------------------------------------------------------------------- /build.gradle: -------------------------------------------------------------------------------- 1 | // Top-level build file where you can add configuration options common to all sub-projects/modules. 2 | buildscript { 3 | ext.kotlin_version = "1.3.72" 4 | repositories { 5 | google() 6 | jcenter() 7 | } 8 | dependencies { 9 | classpath "com.android.tools.build:gradle:4.0.0" 10 | classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" 11 | 12 | // NOTE: Do not place your application dependencies here; they belong 13 | // in the individual module build.gradle files 14 | } 15 | } 16 | 17 | allprojects { 18 | repositories { 19 | google() 20 | jcenter() 21 | } 22 | } 23 | 24 | task clean(type: Delete) { 25 | delete rootProject.buildDir 26 | } -------------------------------------------------------------------------------- /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 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 | # Automatically convert third-party libraries to use AndroidX 19 | android.enableJetifier=true 20 | # Kotlin code style for this project: "official" or "obsolete": 21 | kotlin.code.style=official -------------------------------------------------------------------------------- /gradle/wrapper/gradle-wrapper.jar: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/DemD10/Holder-prefetcher/22e69433539d36c151f066d788735aebfed681c8/gradle/wrapper/gradle-wrapper.jar -------------------------------------------------------------------------------- /gradle/wrapper/gradle-wrapper.properties: -------------------------------------------------------------------------------- 1 | #Sat Jul 25 23:45:56 ALMT 2020 2 | distributionBase=GRADLE_USER_HOME 3 | distributionPath=wrapper/dists 4 | zipStoreBase=GRADLE_USER_HOME 5 | zipStorePath=wrapper/dists 6 | distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-all.zip 7 | -------------------------------------------------------------------------------- /gradlew: -------------------------------------------------------------------------------- 1 | #!/usr/bin/env sh 2 | 3 | ############################################################################## 4 | ## 5 | ## Gradle start up script for UN*X 6 | ## 7 | ############################################################################## 8 | 9 | # Attempt to set APP_HOME 10 | # Resolve links: $0 may be a link 11 | PRG="$0" 12 | # Need this for relative symlinks. 13 | while [ -h "$PRG" ] ; do 14 | ls=`ls -ld "$PRG"` 15 | link=`expr "$ls" : '.*-> \(.*\)$'` 16 | if expr "$link" : '/.*' > /dev/null; then 17 | PRG="$link" 18 | else 19 | PRG=`dirname "$PRG"`"/$link" 20 | fi 21 | done 22 | SAVED="`pwd`" 23 | cd "`dirname \"$PRG\"`/" >/dev/null 24 | APP_HOME="`pwd -P`" 25 | cd "$SAVED" >/dev/null 26 | 27 | APP_NAME="Gradle" 28 | APP_BASE_NAME=`basename "$0"` 29 | 30 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 31 | DEFAULT_JVM_OPTS="" 32 | 33 | # Use the maximum available, or set MAX_FD != -1 to use that value. 34 | MAX_FD="maximum" 35 | 36 | warn () { 37 | echo "$*" 38 | } 39 | 40 | die () { 41 | echo 42 | echo "$*" 43 | echo 44 | exit 1 45 | } 46 | 47 | # OS specific support (must be 'true' or 'false'). 48 | cygwin=false 49 | msys=false 50 | darwin=false 51 | nonstop=false 52 | case "`uname`" in 53 | CYGWIN* ) 54 | cygwin=true 55 | ;; 56 | Darwin* ) 57 | darwin=true 58 | ;; 59 | MINGW* ) 60 | msys=true 61 | ;; 62 | NONSTOP* ) 63 | nonstop=true 64 | ;; 65 | esac 66 | 67 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar 68 | 69 | # Determine the Java command to use to start the JVM. 70 | if [ -n "$JAVA_HOME" ] ; then 71 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then 72 | # IBM's JDK on AIX uses strange locations for the executables 73 | JAVACMD="$JAVA_HOME/jre/sh/java" 74 | else 75 | JAVACMD="$JAVA_HOME/bin/java" 76 | fi 77 | if [ ! -x "$JAVACMD" ] ; then 78 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME 79 | 80 | Please set the JAVA_HOME variable in your environment to match the 81 | location of your Java installation." 82 | fi 83 | else 84 | JAVACMD="java" 85 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 86 | 87 | Please set the JAVA_HOME variable in your environment to match the 88 | location of your Java installation." 89 | fi 90 | 91 | # Increase the maximum file descriptors if we can. 92 | if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then 93 | MAX_FD_LIMIT=`ulimit -H -n` 94 | if [ $? -eq 0 ] ; then 95 | if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then 96 | MAX_FD="$MAX_FD_LIMIT" 97 | fi 98 | ulimit -n $MAX_FD 99 | if [ $? -ne 0 ] ; then 100 | warn "Could not set maximum file descriptor limit: $MAX_FD" 101 | fi 102 | else 103 | warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT" 104 | fi 105 | fi 106 | 107 | # For Darwin, add options to specify how the application appears in the dock 108 | if $darwin; then 109 | GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\"" 110 | fi 111 | 112 | # For Cygwin, switch paths to Windows format before running java 113 | if $cygwin ; then 114 | APP_HOME=`cygpath --path --mixed "$APP_HOME"` 115 | CLASSPATH=`cygpath --path --mixed "$CLASSPATH"` 116 | JAVACMD=`cygpath --unix "$JAVACMD"` 117 | 118 | # We build the pattern for arguments to be converted via cygpath 119 | ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null` 120 | SEP="" 121 | for dir in $ROOTDIRSRAW ; do 122 | ROOTDIRS="$ROOTDIRS$SEP$dir" 123 | SEP="|" 124 | done 125 | OURCYGPATTERN="(^($ROOTDIRS))" 126 | # Add a user-defined pattern to the cygpath arguments 127 | if [ "$GRADLE_CYGPATTERN" != "" ] ; then 128 | OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)" 129 | fi 130 | # Now convert the arguments - kludge to limit ourselves to /bin/sh 131 | i=0 132 | for arg in "$@" ; do 133 | CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -` 134 | CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option 135 | 136 | if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition 137 | eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"` 138 | else 139 | eval `echo args$i`="\"$arg\"" 140 | fi 141 | i=$((i+1)) 142 | done 143 | case $i in 144 | (0) set -- ;; 145 | (1) set -- "$args0" ;; 146 | (2) set -- "$args0" "$args1" ;; 147 | (3) set -- "$args0" "$args1" "$args2" ;; 148 | (4) set -- "$args0" "$args1" "$args2" "$args3" ;; 149 | (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;; 150 | (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;; 151 | (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;; 152 | (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;; 153 | (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;; 154 | esac 155 | fi 156 | 157 | # Escape application args 158 | save () { 159 | for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done 160 | echo " " 161 | } 162 | APP_ARGS=$(save "$@") 163 | 164 | # Collect all arguments for the java command, following the shell quoting and substitution rules 165 | eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS" 166 | 167 | # by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong 168 | if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then 169 | cd "$(dirname "$0")" 170 | fi 171 | 172 | exec "$JAVACMD" "$@" 173 | -------------------------------------------------------------------------------- /gradlew.bat: -------------------------------------------------------------------------------- 1 | @if "%DEBUG%" == "" @echo off 2 | @rem ########################################################################## 3 | @rem 4 | @rem Gradle startup script for Windows 5 | @rem 6 | @rem ########################################################################## 7 | 8 | @rem Set local scope for the variables with windows NT shell 9 | if "%OS%"=="Windows_NT" setlocal 10 | 11 | set DIRNAME=%~dp0 12 | if "%DIRNAME%" == "" set DIRNAME=. 13 | set APP_BASE_NAME=%~n0 14 | set APP_HOME=%DIRNAME% 15 | 16 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 17 | set DEFAULT_JVM_OPTS= 18 | 19 | @rem Find java.exe 20 | if defined JAVA_HOME goto findJavaFromJavaHome 21 | 22 | set JAVA_EXE=java.exe 23 | %JAVA_EXE% -version >NUL 2>&1 24 | if "%ERRORLEVEL%" == "0" goto init 25 | 26 | echo. 27 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 28 | echo. 29 | echo Please set the JAVA_HOME variable in your environment to match the 30 | echo location of your Java installation. 31 | 32 | goto fail 33 | 34 | :findJavaFromJavaHome 35 | set JAVA_HOME=%JAVA_HOME:"=% 36 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe 37 | 38 | if exist "%JAVA_EXE%" goto init 39 | 40 | echo. 41 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 42 | echo. 43 | echo Please set the JAVA_HOME variable in your environment to match the 44 | echo location of your Java installation. 45 | 46 | goto fail 47 | 48 | :init 49 | @rem Get command-line arguments, handling Windows variants 50 | 51 | if not "%OS%" == "Windows_NT" goto win9xME_args 52 | 53 | :win9xME_args 54 | @rem Slurp the command line arguments. 55 | set CMD_LINE_ARGS= 56 | set _SKIP=2 57 | 58 | :win9xME_args_slurp 59 | if "x%~1" == "x" goto execute 60 | 61 | set CMD_LINE_ARGS=%* 62 | 63 | :execute 64 | @rem Setup the command line 65 | 66 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar 67 | 68 | @rem Execute Gradle 69 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS% 70 | 71 | :end 72 | @rem End local scope for the variables with windows NT shell 73 | if "%ERRORLEVEL%"=="0" goto mainEnd 74 | 75 | :fail 76 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of 77 | rem the _cmd.exe /c_ return code! 78 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 79 | exit /b 1 80 | 81 | :mainEnd 82 | if "%OS%"=="Windows_NT" endlocal 83 | 84 | :omega 85 | -------------------------------------------------------------------------------- /settings.gradle: -------------------------------------------------------------------------------- 1 | include ':app' 2 | rootProject.name = "Holder prefetcher" --------------------------------------------------------------------------------