feat(banner): Phase 8 배너 동작을 보완한다

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerView.kt

@@ -9,6 +9,10 @@ import android.view.View
 import android.widget.FrameLayout
 import android.widget.ImageView
 import android.widget.TextView
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.findViewTreeLifecycleOwner
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.LinearSmoothScroller
 import androidx.recyclerview.widget.PagerSnapHelper
@@ -37,6 +41,19 @@ class BannerView @JvmOverloads constructor(
     private val autoScrollHandler = Handler(Looper.getMainLooper())
     private val autoScrollRunnable = Runnable { moveToNextBanner() }
     private var hasWindowAttachmentForAutoScroll = false
+    private var isLifecycleStartedForAutoScroll = true
+    private var lifecycleOwner: LifecycleOwner? = null
+    private val lifecycleObserver = object : DefaultLifecycleObserver {
+        override fun onStart(owner: LifecycleOwner) {
+            isLifecycleStartedForAutoScroll = true
+            startAutoScrollIfNeeded()
+        }
+
+        override fun onStop(owner: LifecycleOwner) {
+            isLifecycleStartedForAutoScroll = false
+            stopAutoScroll()
+        }
+    }
     private val bannerScrollListener = object : RecyclerView.OnScrollListener() {
         override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
             when (newState) {
@@ -66,11 +83,13 @@ class BannerView @JvmOverloads constructor(
     override fun onAttachedToWindow() {
         super.onAttachedToWindow()
         hasWindowAttachmentForAutoScroll = true
+        observeLifecycleOwner()
         startAutoScrollIfNeeded()
     }
 
     override fun onDetachedFromWindow() {
         stopAutoScroll()
+        clearLifecycleOwner()
         hasWindowAttachmentForAutoScroll = false
         super.onDetachedFromWindow()
     }
@@ -96,7 +115,7 @@ class BannerView @JvmOverloads constructor(
 
     fun setItems(items: List<BannerItem>) {
         this.items = items
-        currentIndex = BannerState.from(items.size, currentIndex).currentIndex
+        currentIndex = 0
         visibility = if (items.isEmpty()) GONE else VISIBLE
         stopAutoScroll()
         adapter.submitItems(items)
@@ -187,6 +206,7 @@ class BannerView @JvmOverloads constructor(
     private fun startAutoScrollIfNeeded() {
         stopAutoScroll()
         if (!hasWindowAttachmentForAutoScroll) return
+        if (!isLifecycleStartedForAutoScroll) return
         if (BannerState.from(items.size, currentIndex).displayMode != BannerDisplayMode.Carousel) return
         autoScrollHandler.postDelayed(autoScrollRunnable, AUTO_SCROLL_INTERVAL_MS)
     }
@@ -196,9 +216,15 @@ class BannerView @JvmOverloads constructor(
     }
 
     private fun updateCurrentIndexFromSnap() {
-        val layoutManager = requireNotNull(recyclerView).layoutManager ?: return
+        val recyclerView = requireNotNull(recyclerView)
-        val snapView = snapHelper.findSnapView(layoutManager) ?: return
+        val layoutManager = recyclerView.layoutManager ?: return
-        val position = layoutManager.getPosition(snapView)
+        val snapView = snapHelper.findSnapView(layoutManager)
+        val snapPosition = snapView?.let(layoutManager::getPosition) ?: RecyclerView.NO_POSITION
+        val position = if (snapPosition == RecyclerView.NO_POSITION) {
+            currentAdapterPosition
+        } else {
+            snapPosition
+        }
         currentAdapterPosition = position
         currentIndex = adapter.toRealIndex(position)
         updateCounter()
@@ -213,10 +239,25 @@ class BannerView @JvmOverloads constructor(
         val formatted = BannerCounterFormatter.format(state.currentIndex, items.size)
         val parts = formatted.split(" ")
         currentIndexText?.text = parts[0]
-        separatorText?.text = parts[1]
+        separatorText?.text = " ${parts[1]} "
         totalCountText?.text = parts[2]
     }
 
+    private fun observeLifecycleOwner() {
+        val owner = findViewTreeLifecycleOwner() ?: return
+        if (lifecycleOwner === owner) return
+        clearLifecycleOwner()
+        lifecycleOwner = owner
+        isLifecycleStartedForAutoScroll = owner.lifecycle.currentState.isAtLeast(Lifecycle.State.STARTED)
+        owner.lifecycle.addObserver(lifecycleObserver)
+    }
+
+    private fun clearLifecycleOwner() {
+        lifecycleOwner?.lifecycle?.removeObserver(lifecycleObserver)
+        lifecycleOwner = null
+        isLifecycleStartedForAutoScroll = true
+    }
+
     private fun Int.dpToPx(): Int = (this * resources.displayMetrics.density).roundToInt()
 
     companion object {

app/src/main/res/layout/view_banner.xml

@@ -33,7 +33,7 @@
 
         <TextView
             android:id="@+id/tv_banner_current_index"
-            style="@style/Typography.Caption2"
+            style="@style/Typography.Body5"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:textColor="@color/white"
@@ -41,7 +41,7 @@
 
         <TextView
             android:id="@+id/tv_banner_counter_separator"
-            style="@style/Typography.Caption2"
+            style="@style/Typography.Body5"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:textColor="@color/gray_400"
@@ -49,7 +49,7 @@
 
         <TextView
             android:id="@+id/tv_banner_total_count"
-            style="@style/Typography.Caption2"
+            style="@style/Typography.Body5"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:textColor="@color/gray_400"

app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerViewTest.kt

@@ -8,6 +8,8 @@ import android.view.View.MeasureSpec
 import android.widget.FrameLayout
 import android.widget.ImageView
 import android.widget.TextView
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleRegistry
 import androidx.recyclerview.widget.RecyclerView
 import androidx.test.core.app.ApplicationProvider
 import kr.co.vividnext.sodalive.R
@@ -101,6 +103,26 @@ class BannerViewTest {
         assertEquals("02", view.findViewById<TextView>(R.id.tv_banner_total_count).text.toString())
     }
 
+    @Test
+    fun `배너 view counter는 PRD 시각 형식과 색상 및 14sp 크기를 유지한다`() {
+        val view = inflateBannerView()
+
+        view.setItems(listOf(sampleItem("1"), sampleItem("2")))
+
+        val currentIndex = view.findViewById<TextView>(R.id.tv_banner_current_index)
+        val separator = view.findViewById<TextView>(R.id.tv_banner_counter_separator)
+        val totalCount = view.findViewById<TextView>(R.id.tv_banner_total_count)
+        val displayedCounter = currentIndex.text.toString() + separator.text + totalCount.text
+
+        assertEquals("01 / 02", displayedCounter)
+        assertEquals(view.resources.getColor(R.color.white), currentIndex.currentTextColor)
+        assertEquals(view.resources.getColor(R.color.gray_400), separator.currentTextColor)
+        assertEquals(view.resources.getColor(R.color.gray_400), totalCount.currentTextColor)
+        assertEquals(14f, currentIndex.textSize / view.resources.displayMetrics.scaledDensity)
+        assertEquals(14f, separator.textSize / view.resources.displayMetrics.scaledDensity)
+        assertEquals(14f, totalCount.textSize / view.resources.displayMetrics.scaledDensity)
+    }
+
     @Test
     fun `배너 view는 preview 속성의 count와 current index를 counter에 반영한다`() {
         val context = ApplicationProvider.getApplicationContext<Context>()
@@ -293,6 +315,27 @@ class BannerViewTest {
         assertEquals("01", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
     }
 
+    @Test
+    fun `배너 view는 lifecycle stop에서 자동 이동을 멈추고 start에서 다시 예약한다`() {
+        val owner = TestLifecycleOwner()
+        val view = inflateBannerView()
+        view.setTag(lifecycleOwnerTagId(), owner)
+
+        view.setItems(listOf(sampleItem("1"), sampleItem("2")))
+        view.measure(exactly(402.dpToPx()), exactly(402.dpToPx()))
+        view.layout(0, 0, 402.dpToPx(), 402.dpToPx())
+        view.dispatchAttachedForTest()
+        owner.handleEvent(Lifecycle.Event.ON_START)
+        owner.handleEvent(Lifecycle.Event.ON_STOP)
+        shadowOf(android.os.Looper.getMainLooper()).idleFor(Duration.ofMillis(5_000))
+
+        assertEquals("01", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+
+        owner.handleEvent(Lifecycle.Event.ON_START)
+        shadowOf(android.os.Looper.getMainLooper()).idleFor(Duration.ofMillis(5_000))
+        assertEquals("02", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+    }
+
     @Test
     fun `배너 view는 단일 item이면 attach 후 5초가 지나도 자동 이동하지 않는다`() {
         val view = inflateBannerView()
@@ -346,6 +389,47 @@ class BannerViewTest {
         assertEquals("01", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
     }
 
+    @Test
+    fun `배너 view는 새 목록을 설정하면 첫 번째 배너 기준으로 다시 시작한다`() {
+        val view = inflateBannerView()
+
+        view.setItems(listOf(sampleItem("1"), sampleItem("2"), sampleItem("3")))
+        view.measure(exactly(402.dpToPx()), exactly(402.dpToPx()))
+        view.layout(0, 0, 402.dpToPx(), 402.dpToPx())
+        view.dispatchAttachedForTest()
+        shadowOf(android.os.Looper.getMainLooper()).idleFor(Duration.ofMillis(5_000))
+        assertEquals("02", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+
+        view.setItems(listOf(sampleItem("4"), sampleItem("5"), sampleItem("6")))
+
+        assertEquals("01", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+        shadowOf(android.os.Looper.getMainLooper()).idleFor(Duration.ofMillis(5_000))
+        assertEquals("02", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+    }
+
+    @Test
+    fun `배너 view는 수동 경계와 빠른 위치 변경 후 idle에서 counter를 실제 index와 동기화한다`() {
+        val view = inflateBannerView()
+        val recyclerView = view.findViewById<RecyclerView>(R.id.rv_banner)
+
+        view.setItems(listOf(sampleItem("1"), sampleItem("2"), sampleItem("3")))
+        val adapter = requireNotNull(recyclerView.adapter as? BannerAdapter)
+        val firstPosition = adapter.startPosition(0)
+        val lastPosition = adapter.startPosition(2)
+
+        view.setCurrentPositionForTest(firstPosition - 1)
+        view.dispatchScrollStateForTest(RecyclerView.SCROLL_STATE_IDLE)
+        assertEquals("03", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+
+        view.setCurrentPositionForTest(lastPosition + 1)
+        view.dispatchScrollStateForTest(RecyclerView.SCROLL_STATE_IDLE)
+        assertEquals("01", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+
+        view.setCurrentPositionForTest(firstPosition + 5)
+        view.dispatchScrollStateForTest(RecyclerView.SCROLL_STATE_IDLE)
+        assertEquals("03", view.findViewById<TextView>(R.id.tv_banner_current_index).text.toString())
+    }
+
     private fun inflateBannerView(): BannerView {
         val context = ApplicationProvider.getApplicationContext<Context>()
         return BannerView(context)
@@ -372,6 +456,7 @@ class BannerViewTest {
     }
 
     private fun BannerView.setCurrentPositionForTest(position: Int) {
+        findViewById<RecyclerView>(R.id.rv_banner).scrollToPosition(position)
         BannerView::class.java.getDeclaredField("currentAdapterPosition").apply {
             isAccessible = true
             setInt(this@setCurrentPositionForTest, position)
@@ -407,4 +492,20 @@ class BannerViewTest {
         val context = ApplicationProvider.getApplicationContext<Context>()
         return (this * context.resources.displayMetrics.density).toInt()
     }
+
+    private fun lifecycleOwnerTagId(): Int {
+        return Class.forName("androidx.lifecycle.runtime.R\$id")
+            .getDeclaredField("view_tree_lifecycle_owner")
+            .getInt(null)
+    }
+
+    private class TestLifecycleOwner : androidx.lifecycle.LifecycleOwner {
+        private val registry = LifecycleRegistry(this)
+
+        override val lifecycle: Lifecycle = registry
+
+        fun handleEvent(event: Lifecycle.Event) {
+            registry.handleLifecycleEvent(event)
+        }
+    }
 }