Android Compose keeps recomposing - android-jetpack-compose

Question

I am writing a LazyColumn, items are LazyRows.
But the PasserItem keeps recomposing when gently swipe, I see log keep pringing and never stop.
I come here for help.
Why this happen, any state wrong?
I find tow ways stop it. remove items in MemoList2, or remove AnimatedVisibility in PasserItem2. Why these ways help?
Is my pattern implementing get-in animation with AnimatedVisibility proper?(I want anim run only once)
data class Passer(val username: String?, val memo: Array<String>)
MainActivity#onCreate
val live = MutableLiveData<Array<Passer>>()
live.value = Array(100) {
Passer("$it", arrayOf("$it", "$it"))
}
setContent {
PasserTheme {
Home2(live)
}
}
private const val TAG = "Home"
#Composable
fun Home2(passersLive: LiveData<Array<Passer>>) {
val passers = passersLive.observeAsState(initial = arrayOf())
Scaffold {
Box(
modifier = Modifier.fillMaxSize(),
content = { PasserList2(passers = passers.value) }
)
}
}
#OptIn(ExperimentalAnimationApi::class)
#Composable
private fun PasserList2(passers: Array<Passer>) {
Log.d(TAG, "PasserList")
LazyColumn(modifier = Modifier.fillMaxSize()) {
Log.d(TAG, "LazyColumn ${passers.size}")
items(passers.size) { index ->
PasserItem2(passer = passers[index])
if (index != passers.size - 1) {
Spacer(modifier = Modifier.height(32.dp))
}
}
}
}
#OptIn(ExperimentalAnimationApi::class)
#Composable
private fun PasserItem2(passer: Passer) {
Log.d(TAG, "PasserItem ${passer.username}")
var visibility by remember { mutableStateOf(false) }
LaunchedEffect(key1 = visibility) {
Log.d(TAG, "PasserItem LaunchedEffect")
visibility = true
}
Log.d(TAG, "PasserItem visible $visibility")
AnimatedVisibility(visible = visibility) {
Column(
modifier = Modifier
.fillMaxWidth()
.background(MaterialTheme.colors.onBackground.copy(alpha = 0.1F))
.padding(16.dp)
) {
MemoList2(passer.memo)
}
}
}
#Composable
private fun MemoList2(memo: Array<String>) {
Log.d(TAG, "MemoList")
LazyRow(modifier = Modifier.fillMaxWidth()) {
items(memo.size) { }
}
}
buildscript {
ext {
compose_version = '1.2.0-alpha07'
my_dependency = [:]
my_dependency.gradle = "com.android.tools.build:gradle:7.0.4"
my_dependency.kotlin_gradle = "org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.10"
my_dependency.core_ktx = "androidx.core:core-ktx:1.7.0"
my_dependency.compose_ui_ui = "androidx.compose.ui:ui:1.2.0-alpha07"
my_dependency.compose_material = "androidx.compose.material:material:1.1.1"
my_dependency.compose_ui_tooling_preview = "androidx.compose.ui:ui-tooling-preview:1.1.1"
my_dependency.compose_activity = "androidx.activity:activity-compose:1.4.0"
my_dependency.compose_runtime_livedata = "androidx.compose.runtime:runtime-livedata:1.1.1"
my_dependency.compose_ui_tooling = "androidx.compose.ui:ui-tooling:1.1.1"
versions = [:]
versions.versionCode = 1
versions.versionName = "1.0"
versions.compileSdkVersion = 31
versions.buildToolsVersion = '33.0.1'
versions.minSdk = 30
versions.targetSdk = 31
}
repositories {
google()
mavenCentral()
}
dependencies {
classpath "$my_dependency.gradle"
classpath "$my_dependency.kotlin_gradle"
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
plugins {
id 'com.android.application'
id 'kotlin-android'
}
android {
compileSdk 31
defaultConfig {
applicationId "ycr.pass"
minSdk versions.minSdk
targetSdk versions.targetSdk
versionCode versions.versionCode
versionName versions.versionName
vectorDrawables {
useSupportLibrary true
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_11
targetCompatibility JavaVersion.VERSION_11
}
kotlinOptions {
jvmTarget = '11'
useIR = true
}
buildFeatures {
compose true
}
composeOptions {
kotlinCompilerExtensionVersion compose_version
}
packagingOptions {
resources {
excludes += '/META-INF/{AL2.0,LGPL2.1}'
}
}
}
dependencies {
implementation my_dependency.core_ktx
implementation my_dependency.compose_ui_ui
implementation my_dependency.compose_material
implementation my_dependency.compose_ui_tooling_preview
implementation my_dependency.compose_activity
implementation my_dependency.compose_runtime_livedata
debugImplementation my_dependency.compose_ui_tooling
}