Merge "Fix MediaCarousel in RTL" into rvc-dev am: b01bd6a560

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11988335

Change-Id: I2df164d6b9c7308a245cdb95837a92c1bc8f2b86

packages/SystemUI/src/com/android/systemui/media/MediaCarouselController.kt

@@ -2,6 +2,7 @@ package com.android.systemui.media
 
 import android.content.Context
 import android.content.Intent
+import android.content.res.Configuration
 import android.graphics.Color
 import android.provider.Settings.ACTION_MEDIA_CONTROLS_SETTINGS
 import android.view.LayoutInflater
@@ -96,7 +97,6 @@ class MediaCarouselController @Inject constructor(
      * The measured height of the carousel
      */
     private var carouselMeasureHeight: Int = 0
-    private var playerWidthPlusPadding: Int = 0
     private var desiredHostState: MediaHostState? = null
     private val mediaCarousel: MediaScrollView
     private val mediaCarouselScrollHandler: MediaCarouselScrollHandler
@@ -108,6 +108,15 @@ class MediaCarouselController @Inject constructor(
     private val pageIndicator: PageIndicator
     private val visualStabilityCallback: VisualStabilityManager.Callback
     private var needsReordering: Boolean = false
+    private var isRtl: Boolean = false
+        set(value) {
+            if (value != field) {
+                field = value
+                mediaFrame.layoutDirection =
+                        if (value) View.LAYOUT_DIRECTION_RTL else View.LAYOUT_DIRECTION_LTR
+                mediaCarouselScrollHandler.scrollToStart()
+            }
+        }
     private var currentlyExpanded = true
         set(value) {
             if (field != value) {
@@ -126,6 +135,11 @@ class MediaCarouselController @Inject constructor(
         override fun onOverlayChanged() {
             inflateSettingsButton()
         }
+
+        override fun onConfigChanged(newConfig: Configuration?) {
+            if (newConfig == null) return
+            isRtl = newConfig.layoutDirection == View.LAYOUT_DIRECTION_RTL
+        }
     }
 
     init {
@@ -135,6 +149,7 @@ class MediaCarouselController @Inject constructor(
         mediaCarouselScrollHandler = MediaCarouselScrollHandler(mediaCarousel, pageIndicator,
                 executor, mediaDataManager::onSwipeToDismiss, this::updatePageIndicatorLocation,
                 falsingManager)
+        isRtl = context.resources.configuration.layoutDirection == View.LAYOUT_DIRECTION_RTL
         inflateSettingsButton()
         mediaContent = mediaCarousel.requireViewById(R.id.media_carousel)
         configurationController.addCallback(configListener)
@@ -144,7 +159,7 @@ class MediaCarouselController @Inject constructor(
                 reorderAllPlayers()
             }
             // Let's reset our scroll position
-            mediaCarousel.scrollX = 0
+            mediaCarouselScrollHandler.scrollToStart()
         }
         visualStabilityManager.addReorderingAllowedCallback(visualStabilityCallback,
                 true /* persistent */)
@@ -196,8 +211,13 @@ class MediaCarouselController @Inject constructor(
     }
 
     private fun inflateMediaCarousel(): ViewGroup {
-        return LayoutInflater.from(context).inflate(R.layout.media_carousel,
+        val mediaCarousel = LayoutInflater.from(context).inflate(R.layout.media_carousel,
                 UniqueObjectHostView(context), false) as ViewGroup
+        // Because this is inflated when not attached to the true view hierarchy, it resolves some
+        // potential issues to force that the layout direction is defined by the locale
+        // (rather than inherited from the parent, which would resolve to LTR when unattached).
+        mediaCarousel.layoutDirection = View.LAYOUT_DIRECTION_LOCALE
+        return mediaCarousel
     }
 
     private fun reorderAllPlayers() {
@@ -313,8 +333,12 @@ class MediaCarouselController @Inject constructor(
 
     private fun updatePageIndicatorLocation() {
         // Update the location of the page indicator, carousel clipping
-        pageIndicator.translationX = (currentCarouselWidth - pageIndicator.width) / 2.0f +
+        val translationX = if (isRtl) {
-                mediaCarouselScrollHandler.contentTranslation
+            (pageIndicator.width - currentCarouselWidth) / 2.0f
+        } else {
+            (currentCarouselWidth - pageIndicator.width) / 2.0f
+        }
+        pageIndicator.translationX = translationX + mediaCarouselScrollHandler.contentTranslation
         val layoutParams = pageIndicator.layoutParams as ViewGroup.MarginLayoutParams
         pageIndicator.translationY = (currentCarouselHeight - pageIndicator.height -
                 layoutParams.bottomMargin).toFloat()
@@ -334,7 +358,8 @@ class MediaCarouselController @Inject constructor(
         if (width != currentCarouselWidth || height != currentCarouselHeight) {
             currentCarouselWidth = width
             currentCarouselHeight = height
-            mediaCarouselScrollHandler.setCarouselBounds(currentCarouselWidth, currentCarouselHeight)
+            mediaCarouselScrollHandler.setCarouselBounds(
+                    currentCarouselWidth, currentCarouselHeight)
             updatePageIndicatorLocation()
         }
     }
@@ -348,7 +373,7 @@ class MediaCarouselController @Inject constructor(
         if (currentlyShowingOnlyActive != endShowsActive ||
                 ((currentTransitionProgress != 1.0f && currentTransitionProgress != 0.0f) &&
                             startShowsActive != endShowsActive)) {
-            /// Whenever we're transitioning from between differing states or the endstate differs
+            // Whenever we're transitioning from between differing states or the endstate differs
             // we reset the translation
             currentlyShowingOnlyActive = endShowsActive
             mediaCarouselScrollHandler.resetTranslation(animate = true)
@@ -416,14 +441,15 @@ class MediaCarouselController @Inject constructor(
                 height != carouselMeasureWidth && height != 0) {
             carouselMeasureWidth = width
             carouselMeasureHeight = height
-            playerWidthPlusPadding = carouselMeasureWidth + context.resources.getDimensionPixelSize(
+            val playerWidthPlusPadding = carouselMeasureWidth +
-                    R.dimen.qs_media_padding)
+                    context.resources.getDimensionPixelSize(R.dimen.qs_media_padding)
-            mediaCarouselScrollHandler.playerWidthPlusPadding = playerWidthPlusPadding
             // Let's remeasure the carousel
             val widthSpec = desiredHostState?.measurementInput?.widthMeasureSpec ?: 0
             val heightSpec = desiredHostState?.measurementInput?.heightMeasureSpec ?: 0
             mediaCarousel.measure(widthSpec, heightSpec)
             mediaCarousel.layout(0, 0, width, mediaCarousel.measuredHeight)
+            // Update the padding after layout; view widths are used in RTL to calculate scrollX
+            mediaCarouselScrollHandler.playerWidthPlusPadding = playerWidthPlusPadding
         }
     }
 }

packages/SystemUI/src/com/android/systemui/media/MediaCarouselScrollHandler.kt

@@ -58,6 +58,10 @@ class MediaCarouselScrollHandler(
     private var translationChangedListener: () -> Unit,
     private val falsingManager: FalsingManager
 ) {
+    /**
+     * Is the view in RTL
+     */
+    val isRtl: Boolean get() = scrollView.isLayoutRtl
     /**
      * Do we need falsing protection?
      */
@@ -121,14 +125,14 @@ class MediaCarouselScrollHandler(
             field = value
             // The player width has changed, let's update the scroll position to make sure
             // it's still at the same place
-            var newScroll = activeMediaIndex * playerWidthPlusPadding
+            var newRelativeScroll = activeMediaIndex * playerWidthPlusPadding
             if (scrollIntoCurrentMedia > playerWidthPlusPadding) {
-                newScroll += playerWidthPlusPadding -
+                newRelativeScroll += playerWidthPlusPadding -
                         (scrollIntoCurrentMedia - playerWidthPlusPadding)
             } else {
-                newScroll += scrollIntoCurrentMedia
+                newRelativeScroll += scrollIntoCurrentMedia
             }
-            scrollView.scrollX = newScroll
+            scrollView.relativeScrollX = newRelativeScroll
         }
 
     /**
@@ -184,8 +188,9 @@ class MediaCarouselScrollHandler(
             if (playerWidthPlusPadding == 0) {
                 return
             }
-            onMediaScrollingChanged(scrollX / playerWidthPlusPadding,
+            val relativeScrollX = scrollView.relativeScrollX
-                    scrollX % playerWidthPlusPadding)
+            onMediaScrollingChanged(relativeScrollX / playerWidthPlusPadding,
+                    relativeScrollX % playerWidthPlusPadding)
         }
     }
 
@@ -222,11 +227,19 @@ class MediaCarouselScrollHandler(
                     Math.abs(contentTranslation))
             val settingsTranslation = (1.0f - settingsOffset) * -settingsButton.width *
                     SETTINGS_BUTTON_TRANSLATION_FRACTION
-            val newTranslationX: Float
+            val newTranslationX = if (isRtl) {
-            if (contentTranslation > 0) {
+                // In RTL, the 0-placement is on the right side of the view, not the left...
-                newTranslationX = settingsTranslation
+                if (contentTranslation > 0) {
+                    -(scrollView.width - settingsTranslation - settingsButton.width)
+                } else {
+                    -settingsTranslation
+                }
             } else {
-                newTranslationX = scrollView.width - settingsTranslation - settingsButton.width
+                if (contentTranslation > 0) {
+                    settingsTranslation
+                } else {
+                    scrollView.width - settingsTranslation - settingsButton.width
+                }
             }
             val rotation = (1.0f - settingsOffset) * 50
             settingsButton.rotation = rotation * -Math.signum(contentTranslation)
@@ -259,26 +272,26 @@ class MediaCarouselScrollHandler(
         }
         if (isUp || motionEvent.action == MotionEvent.ACTION_CANCEL) {
             // It's an up and the fling didn't take it above
-            val pos = scrollView.scrollX % playerWidthPlusPadding
+            val relativePos = scrollView.relativeScrollX % playerWidthPlusPadding
-            val scollXAmount: Int
+            val scrollXAmount: Int
-            if (pos > playerWidthPlusPadding / 2) {
+            if (relativePos > playerWidthPlusPadding / 2) {
-                scollXAmount = playerWidthPlusPadding - pos
+                scrollXAmount = playerWidthPlusPadding - relativePos
             } else {
-                scollXAmount = -1 * pos
+                scrollXAmount = -1 * relativePos
             }
-            if (scollXAmount != 0) {
+            if (scrollXAmount != 0) {
                 // Delay the scrolling since scrollView calls springback which cancels
                 // the animation again..
                 mainExecutor.execute {
-                    scrollView.smoothScrollBy(scollXAmount, 0)
+                    scrollView.smoothScrollBy(if (isRtl) -scrollXAmount else scrollXAmount, 0)
                 }
             }
             val currentTranslation = scrollView.getContentTranslation()
             if (currentTranslation != 0.0f) {
                 // We started a Swipe but didn't end up with a fling. Let's either go to the
                 // dismissed position or go back.
-                val springBack = Math.abs(currentTranslation) < getMaxTranslation() / 2
+                val springBack = Math.abs(currentTranslation) < getMaxTranslation() / 2 ||
-                        || isFalseTouch()
+                        isFalseTouch()
                 val newTranslation: Float
                 if (springBack) {
                     newTranslation = 0.0f
@@ -313,9 +326,11 @@ class MediaCarouselScrollHandler(
         return gestureDetector.onTouchEvent(motionEvent)
     }
 
-    fun onScroll(down: MotionEvent,
+    fun onScroll(
-                 lastMotion: MotionEvent,
+        down: MotionEvent,
-                 distanceX: Float): Boolean {
+        lastMotion: MotionEvent,
+        distanceX: Float
+    ): Boolean {
         val totalX = lastMotion.x - down.x
         val currentTranslation = scrollView.getContentTranslation()
         if (currentTranslation != 0.0f ||
@@ -339,8 +354,8 @@ class MediaCarouselScrollHandler(
                 } // Otherwise we don't have do do anything, and will remove the unrubberbanded
                 // translation
             }
-            if (Math.signum(newTranslation) != Math.signum(currentTranslation)
+            if (Math.signum(newTranslation) != Math.signum(currentTranslation) &&
-                    && currentTranslation != 0.0f) {
+                    currentTranslation != 0.0f) {
                 // We crossed the 0.0 threshold of the translation. Let's see if we're allowed
                 // to scroll into the new direction
                 if (scrollView.canScrollHorizontally(-newTranslation.toInt())) {
@@ -394,9 +409,10 @@ class MediaCarouselScrollHandler(
             scrollView.animationTargetX = newTranslation
         } else {
             // We're flinging the player! Let's go either to the previous or to the next player
-            val pos = scrollView.scrollX
+            val pos = scrollView.relativeScrollX
             val currentIndex = if (playerWidthPlusPadding > 0) pos / playerWidthPlusPadding else 0
-            var destIndex = if (vX <= 0) currentIndex + 1 else currentIndex
+            val flungTowardEnd = if (isRtl) vX > 0 else vX < 0
+            var destIndex = if (flungTowardEnd) currentIndex + 1 else currentIndex
             destIndex = Math.max(0, destIndex)
             destIndex = Math.min(mediaContent.getChildCount() - 1, destIndex)
             val view = mediaContent.getChildAt(destIndex)
@@ -438,8 +454,14 @@ class MediaCarouselScrollHandler(
             activeMediaIndex = newIndex
             updatePlayerVisibilities()
         }
-        val location = activeMediaIndex.toFloat() + if (playerWidthPlusPadding > 0)
+        val relativeLocation = activeMediaIndex.toFloat() + if (playerWidthPlusPadding > 0)
             scrollInAmount.toFloat() / playerWidthPlusPadding else 0f
+        // Fix the location, because PageIndicator does not handle RTL internally
+        val location = if (isRtl) {
+            mediaContent.childCount - relativeLocation - 1
+        } else {
+            relativeLocation
+        }
         pageIndicator.setLocation(location)
         updateClipToOutline()
     }
@@ -480,13 +502,20 @@ class MediaCarouselScrollHandler(
      * where it was and update our scroll position.
      */
     fun onPrePlayerRemoved(removed: MediaControlPanel) {
-        val beforeActive = mediaContent.indexOfChild(removed.view?.player) <= activeMediaIndex
+        val removedIndex = mediaContent.indexOfChild(removed.view?.player)
+        // If the removed index is less than the activeMediaIndex, then we need to decrement it.
+        // RTL has no effect on this, because indices are always relative (start-to-end).
+        // Update the index 'manually' since we won't always get a call to onMediaScrollingChanged
+        val beforeActive = removedIndex <= activeMediaIndex
         if (beforeActive) {
-            // also update the index here since the scroll below might not always lead
-            // to a scrolling changed
             activeMediaIndex = Math.max(0, activeMediaIndex - 1)
-            scrollView.scrollX = Math.max(scrollView.scrollX -
+        }
-                    playerWidthPlusPadding, 0)
+        // 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
+        if (leftOfActive) {
+            scrollView.scrollX = Math.max(scrollView.scrollX - playerWidthPlusPadding, 0)
         }
     }
 
@@ -501,6 +530,13 @@ class MediaCarouselScrollHandler(
         }
     }
 
+    /**
+     * Reset the MediaScrollView to the start.
+     */
+    fun scrollToStart() {
+        scrollView.relativeScrollX = 0
+    }
+
     companion object {
         private val CONTENT_TRANSLATION = object : FloatPropertyCompat<MediaCarouselScrollHandler>(
                 "contentTranslation") {

packages/SystemUI/src/com/android/systemui/media/MediaScrollView.kt

@@ -15,7 +15,10 @@ import com.android.systemui.util.animation.physicsAnimator
  * when only measuring children but not the parent, when trying to apply a new scroll position
  */
 class MediaScrollView @JvmOverloads constructor(
-    context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0)
+    context: Context,
+    attrs: AttributeSet? = null,
+    defStyleAttr: Int = 0
+)
     : HorizontalScrollView(context, attrs, defStyleAttr) {
 
     lateinit var contentContainer: ViewGroup
@@ -37,6 +40,26 @@ class MediaScrollView @JvmOverloads constructor(
         contentContainer.translationX
     }
 
+    /**
+     * Convert between the absolute (left-to-right) and relative (start-to-end) scrollX of the media
+     * carousel.  The player indices are always relative (start-to-end) and the scrollView.scrollX
+     * is always absolute.  This function is its own inverse.
+     */
+    private fun transformScrollX(scrollX: Int): Int = if (isLayoutRtl) {
+        contentContainer.width - width - scrollX
+    } else {
+        scrollX
+    }
+
+    /**
+     * Get the layoutDirection-relative (start-to-end) scroll X position of the carousel.
+     */
+    var relativeScrollX: Int
+        get() = transformScrollX(scrollX)
+        set(value) {
+            scrollX = transformScrollX(value)
+        }
+
     /**
      * Allow all scrolls to go through, use base implementation
      */
@@ -55,15 +78,15 @@ class MediaScrollView @JvmOverloads constructor(
     }
 
     override fun onInterceptTouchEvent(ev: MotionEvent?): Boolean {
-        var intercept = false;
+        var intercept = false
         touchListener?.let {
             intercept = it.onInterceptTouchEvent(ev)
         }
-        return super.onInterceptTouchEvent(ev) || intercept;
+        return super.onInterceptTouchEvent(ev) || intercept
     }
 
     override fun onTouchEvent(ev: MotionEvent?): Boolean {
-        var touch = false;
+        var touch = false
         touchListener?.let {
             touch = it.onTouchEvent(ev)
         }
@@ -75,9 +98,17 @@ class MediaScrollView @JvmOverloads constructor(
         contentContainer = getChildAt(0) as ViewGroup
     }
 
-    override fun overScrollBy(deltaX: Int, deltaY: Int, scrollX: Int, scrollY: Int,
+    override fun overScrollBy(
-                              scrollRangeX: Int, scrollRangeY: Int, maxOverScrollX: Int,
+        deltaX: Int,
-                              maxOverScrollY: Int, isTouchEvent: Boolean): Boolean {
+        deltaY: Int,
+        scrollX: Int,
+        scrollY: Int,
+        scrollRangeX: Int,
+        scrollRangeY: Int,
+        maxOverScrollX: Int,
+        maxOverScrollY: Int,
+        isTouchEvent: Boolean
+    ): Boolean {
         if (getContentTranslation() != 0.0f) {
             // When we're dismissing we ignore all the scrolling
             return false