Fix media carousel activities in RTL

This CL fixes the change in reordering, players visibility, and media
scroll handler issues in RTL.
On reordering all players, the visible player should be the rightmost player.
On playing a UMO View, onLayout method is called. It adjust the scroll
value in RTL when the view is not laid out. Therefore, we need to set
the scroll value to the relative value.
On removing a player, we need to make sure the scroll view changes the
scroll value if we are on the rightmost player in media carousel.

Bug: 289174065
Bug: 287168003
Test: Manually checked the media carousel using 3 different umos at the
same time.
Test: atest MediaCarouselScrollHandlerTest.

Change-Id: I80a32eab50d3b75cf3e617d7c8e8d961b2eb6b8a

4 files changed, 20 insertions, 3 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselController.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselController.kt
index 38a6a8f3470b..67f10492e16b 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselController.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselController.kt
@@ -606,6 +606,9 @@ constructor(
                 }
                     ?: mediaCarouselScrollHandler.scrollToPlayer(destIndex = mediaIndex)
             }
+        } else if (isRtl && mediaContent.childCount > 0) {
+            // In RTL, Scroll to the first player as it is the rightmost player in media carousel.
+            mediaCarouselScrollHandler.scrollToPlayer(destIndex = 0)
         }
         // Check postcondition: mediaContent should have the same number of children as there
         // are
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
index ec0c40ec69a3..b0ea322cd8ae 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
@@ -282,13 +282,14 @@ class MediaCarouselScrollHandler(
             // It's an up and the fling didn't take it above
             val relativePos = scrollView.relativeScrollX % playerWidthPlusPadding
             val scrollXAmount: Int =
-                if (isRtl xor (relativePos > playerWidthPlusPadding / 2)) {
+                if (relativePos > playerWidthPlusPadding / 2) {
                     playerWidthPlusPadding - relativePos
                 } else {
                     -1 * relativePos
                 }
             if (scrollXAmount != 0) {
-                val newScrollX = scrollView.relativeScrollX + scrollXAmount
+                val dx = if (isRtl) -scrollXAmount else scrollXAmount
+                val newScrollX = scrollView.scrollX + dx
                 // Delay the scrolling since scrollView calls springback which cancels
                 // the animation again..
                 mainExecutor.execute { scrollView.smoothScrollTo(newScrollX, scrollView.scrollY) }
@@ -539,7 +540,8 @@ class MediaCarouselScrollHandler(
         // If the removed media item is "left of" the active one (in an absolute sense), we need to
         // scroll the view to keep that player in view.  This is because scroll position is always
         // calculated from left to right.
-        val leftOfActive = if (isRtl) !beforeActive else beforeActive
+        // For RTL, we need to scroll if the visible media player is the last item.
+        val leftOfActive = if (isRtl && visibleMediaIndex != 0) !beforeActive else beforeActive
         if (leftOfActive) {
             scrollView.scrollX = Math.max(scrollView.scrollX - playerWidthPlusPadding, 0)
         }
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaScrollView.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaScrollView.kt
index 0e0746590776..10512f1c4aed 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaScrollView.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaScrollView.kt
@@ -74,6 +74,14 @@ constructor(context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
             scrollX = transformScrollX(value)
         }
 
+    override fun onLayout(changed: Boolean, l: Int, t: Int, r: Int, b: Int) {
+        if (!isLaidOut && isLayoutRtl) {
+            // Reset scroll because onLayout method overrides RTL scroll if view was not laid out.
+            mScrollX = relativeScrollX
+        }
+        super.onLayout(changed, l, t, r, b)
+    }
+
     /** Allow all scrolls to go through, use base implementation */
     override fun scrollTo(x: Int, y: Int) {
         if (mScrollX != x || mScrollY != y) {
diff --git a/packages/SystemUI/tests/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandlerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandlerTest.kt
index 49f536e26ce6..74b3fce12790 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandlerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandlerTest.kt
@@ -85,6 +85,7 @@ class MediaCarouselScrollHandlerTest : SysuiTestCase() {
     fun testCarouselScroll_shortScroll() {
         whenever(mediaCarousel.isLayoutRtl).thenReturn(false)
         whenever(mediaCarousel.relativeScrollX).thenReturn(300)
+        whenever(mediaCarousel.scrollX).thenReturn(300)
 
         mediaCarousel.touchListener?.onTouchEvent(motionEventUp)
         executor.runAllReady()
@@ -96,6 +97,7 @@ class MediaCarouselScrollHandlerTest : SysuiTestCase() {
     fun testCarouselScroll_shortScroll_isRTL() {
         whenever(mediaCarousel.isLayoutRtl).thenReturn(true)
         whenever(mediaCarousel.relativeScrollX).thenReturn(300)
+        whenever(mediaCarousel.scrollX).thenReturn(carouselWidth - 300)
 
         mediaCarousel.touchListener?.onTouchEvent(motionEventUp)
         executor.runAllReady()
@@ -107,6 +109,7 @@ class MediaCarouselScrollHandlerTest : SysuiTestCase() {
     fun testCarouselScroll_longScroll() {
         whenever(mediaCarousel.isLayoutRtl).thenReturn(false)
         whenever(mediaCarousel.relativeScrollX).thenReturn(600)
+        whenever(mediaCarousel.scrollX).thenReturn(600)
 
         mediaCarousel.touchListener?.onTouchEvent(motionEventUp)
         executor.runAllReady()
@@ -118,6 +121,7 @@ class MediaCarouselScrollHandlerTest : SysuiTestCase() {
     fun testCarouselScroll_longScroll_isRTL() {
         whenever(mediaCarousel.isLayoutRtl).thenReturn(true)
         whenever(mediaCarousel.relativeScrollX).thenReturn(600)
+        whenever(mediaCarousel.scrollX).thenReturn(carouselWidth - 600)
 
         mediaCarousel.touchListener?.onTouchEvent(motionEventUp)
         executor.runAllReady()