From 4636fbc16398cc62e12c241132d16a93023c8563 Mon Sep 17 00:00:00 2001
From: Jeff DeCew <jeffdq@google.com>
Date: Mon, 22 Jun 2020 20:17:23 -0400
Subject: [PATCH] Fix RTL text in TransitionLayout

Fixes: 159656380
Test: manual - video attached to bug
Change-Id: Ic676c69f3bd5072900563947efc3656a5b22ce70
---
 packages/SystemUI/res/layout/media_view.xml   | 19 +++--------
 packages/SystemUI/res/xml/media_collapsed.xml | 33 +++++--------------
 packages/SystemUI/res/xml/media_expanded.xml  |  6 ++--
 .../util/animation/TransitionLayout.kt        | 30 ++++++++++++++---
 4 files changed, 42 insertions(+), 46 deletions(-)

diff --git a/packages/SystemUI/res/layout/media_view.xml b/packages/SystemUI/res/layout/media_view.xml
index 8441282bd46d3..da4cb2478182c 100644
--- a/packages/SystemUI/res/layout/media_view.xml
+++ b/packages/SystemUI/res/layout/media_view.xml
@@ -65,25 +65,16 @@
 
     <!--  Actions must be ordered left-to-right even in RTL layout.  However, they appear in a chain
     with the album art and the title, and must as a group appear at the end of that chain.  This is
-    accomplished by having the guidebox (an invisible view that is positioned around all 5 actions)
-    in the chain with the album art and the title.  The actions are in a LTR chain bounded by that
-    guidebox, and the ambiguity of how wide the guidebox should be is resolved by using a barrier
-    which forces it's starting edge to be as far to the end as possible while fitting the actions.
-    -->
+    accomplished by having all actions appear in a LTR chain within the parent, and then biasing it
+    to the right side, then this barrier is used to bound the text views.  -->
     <androidx.constraintlayout.widget.Barrier
         android:id="@+id/media_action_barrier"
         android:layout_width="0dp"
         android:layout_height="0dp"
         android:orientation="vertical"
+        app:layout_constraintTop_toTopOf="parent"
         app:barrierDirection="start"
-        />
-
-    <View
-        android:id="@+id/media_action_guidebox"
-        android:layout_width="0dp"
-        android:layout_height="48dp"
-        android:layout_marginTop="16dp"
-        android:visibility="invisible"
+        app:constraint_referenced_ids="action0,action1,action2,action3,action4"
         />
 
     <ImageButton
@@ -201,7 +192,6 @@
         android:fontFamily="@*android:string/config_headlineFontFamilyMedium"
         android:singleLine="true"
         android:textColor="@color/media_primary_text"
-        android:textDirection="locale"
         android:textSize="16sp" />
 
     <!-- Artist name -->
@@ -212,7 +202,6 @@
         android:fontFamily="@*android:string/config_headlineFontFamily"
         android:singleLine="true"
         android:textColor="@color/media_secondary_text"
-        android:textDirection="locale"
         android:textSize="14sp" />
 
     <com.android.internal.widget.CachingIconView
diff --git a/packages/SystemUI/res/xml/media_collapsed.xml b/packages/SystemUI/res/xml/media_collapsed.xml
index b17aa42f1e9fb..22534df333f67 100644
--- a/packages/SystemUI/res/xml/media_collapsed.xml
+++ b/packages/SystemUI/res/xml/media_collapsed.xml
@@ -85,10 +85,11 @@
     <!-- Song name -->
     <Constraint
         android:id="@+id/header_title"
-        android:layout_width="0dp"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="17dp"
         android:layout_marginStart="16dp"
+        app:layout_constrainedWidth="true"
         app:layout_constraintTop_toBottomOf="@id/app_name"
         app:layout_constraintBottom_toTopOf="@id/header_artist"
         app:layout_constraintStart_toEndOf="@id/album_art"
@@ -98,10 +99,11 @@
     <!-- Artist name -->
     <Constraint
         android:id="@+id/header_artist"
-        android:layout_width="0dp"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="3dp"
         android:layout_marginBottom="24dp"
+        app:layout_constrainedWidth="true"
         app:layout_constraintTop_toBottomOf="@id/header_title"
         app:layout_constraintStart_toStartOf="@id/header_title"
         app:layout_constraintEnd_toStartOf="@id/media_action_barrier"
@@ -134,27 +136,6 @@
         android:visibility="gone"
         />
 
-    <Constraint
-        android:id="@+id/media_action_barrier"
-        android:layout_width="0dp"
-        android:layout_height="0dp"
-        android:orientation="vertical"
-        app:layout_constraintTop_toTopOf="parent"
-        app:barrierDirection="start"
-        app:constraint_referenced_ids="media_action_guidebox,action0,action1,action2,action3,action4"
-        />
-
-    <Constraint
-        android:id="@+id/media_action_guidebox"
-        android:layout_width="0dp"
-        android:layout_height="48dp"
-        android:layout_marginTop="18dp"
-        android:visibility="invisible"
-        app:layout_constraintTop_toBottomOf="@id/app_name"
-        app:layout_constraintStart_toEndOf="@id/header_title"
-        app:layout_constraintEnd_toEndOf="parent"
-        />
-
     <Constraint
         android:id="@+id/action0"
         android:layout_width="48dp"
@@ -165,8 +146,9 @@
         android:visibility="gone"
         app:layout_constraintHorizontal_chainStyle="packed"
         app:layout_constraintTop_toBottomOf="@id/app_name"
-        app:layout_constraintLeft_toLeftOf="@id/media_action_guidebox"
+        app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toLeftOf="@id/action1"
+        app:layout_constraintHorizontal_bias="1"
         >
     </Constraint>
 
@@ -220,7 +202,8 @@
         app:layout_constraintHorizontal_chainStyle="packed"
         app:layout_constraintTop_toBottomOf="@id/app_name"
         app:layout_constraintLeft_toRightOf="@id/action3"
-        app:layout_constraintRight_toRightOf="@id/media_action_guidebox"
+        app:layout_constraintRight_toRightOf="parent"
+        app:layout_constraintHorizontal_bias="0"
         >
     </Constraint>
 </ConstraintSet>
diff --git a/packages/SystemUI/res/xml/media_expanded.xml b/packages/SystemUI/res/xml/media_expanded.xml
index 8010f97bf560e..36da21de88920 100644
--- a/packages/SystemUI/res/xml/media_expanded.xml
+++ b/packages/SystemUI/res/xml/media_expanded.xml
@@ -83,11 +83,12 @@
     <!-- Song name -->
     <Constraint
         android:id="@+id/header_title"
-        android:layout_width="0dp"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginEnd="@dimen/qs_media_panel_outer_padding"
         android:layout_marginTop="17dp"
         android:layout_marginStart="16dp"
+        app:layout_constrainedWidth="true"
         app:layout_constraintTop_toBottomOf="@+id/app_name"
         app:layout_constraintStart_toEndOf="@id/album_art"
         app:layout_constraintEnd_toEndOf="parent"
@@ -96,10 +97,11 @@
     <!-- Artist name -->
     <Constraint
         android:id="@+id/header_artist"
-        android:layout_width="0dp"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginEnd="@dimen/qs_media_panel_outer_padding"
         android:layout_marginTop="3dp"
+        app:layout_constrainedWidth="true"
         app:layout_constraintTop_toBottomOf="@id/header_title"
         app:layout_constraintStart_toStartOf="@id/header_title"
         app:layout_constraintEnd_toEndOf="parent"
diff --git a/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt b/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
index 19c6b806bb599..f39665671c5e0 100644
--- a/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
+++ b/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
@@ -20,9 +20,11 @@ import android.content.Context
 import android.graphics.Canvas
 import android.graphics.PointF
 import android.graphics.Rect
+import android.text.Layout
 import android.util.AttributeSet
 import android.view.View
 import android.view.ViewTreeObserver
+import android.widget.TextView
 import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.constraintlayout.widget.ConstraintSet
 import com.android.systemui.statusbar.CrossFadeHelper
@@ -85,6 +87,23 @@ class TransitionLayout @JvmOverloads constructor(
         for (i in 0 until childCount) {
             val child = getChildAt(i)
             val widgetState = currentState.widgetStates.get(child.id) ?: continue
+
+            // TextViews which are measured and sized differently should be handled with a
+            // "clip mode", which means we clip explicitly rather than implicitly by passing
+            // different sizes to measure/layout than setLeftTopRightBottom.
+            // Then to accommodate RTL text, we need a "clip shift" which allows us to have the
+            // clipBounds be attached to the right side of the view instead of the left.
+            val clipModeShift =
+                    if (child is TextView && widgetState.width < widgetState.measureWidth) {
+                if (child.layout.getParagraphDirection(0) == Layout.DIR_RIGHT_TO_LEFT) {
+                    widgetState.measureWidth - widgetState.width
+                } else {
+                    0
+                }
+            } else {
+                null
+            }
+
             if (child.measuredWidth != widgetState.measureWidth ||
                     child.measuredHeight != widgetState.measureHeight) {
                 val measureWidthSpec = MeasureSpec.makeMeasureSpec(widgetState.measureWidth,
@@ -94,14 +113,17 @@ class TransitionLayout @JvmOverloads constructor(
                 child.measure(measureWidthSpec, measureHeightSpec)
                 child.layout(0, 0, child.measuredWidth, child.measuredHeight)
             }
-            val left = widgetState.x.toInt() + contentTranslationX
+            val clipShift = clipModeShift ?: 0
+            val left = widgetState.x.toInt() + contentTranslationX - clipShift
             val top = widgetState.y.toInt() + contentTranslationY
-            child.setLeftTopRightBottom(left, top, left + widgetState.width,
-                    top + widgetState.height)
+            val clipMode = clipModeShift != null
+            val boundsWidth = if (clipMode) widgetState.measureWidth else widgetState.width
+            val boundsHeight = if (clipMode) widgetState.measureHeight else widgetState.height
+            child.setLeftTopRightBottom(left, top, left + boundsWidth, top + boundsHeight)
             child.scaleX = widgetState.scale
             child.scaleY = widgetState.scale
             val clipBounds = child.clipBounds ?: Rect()
-            clipBounds.set(0, 0, widgetState.width, widgetState.height)
+            clipBounds.set(clipShift, 0, widgetState.width + clipShift, widgetState.height)
             child.clipBounds = clipBounds
             CrossFadeHelper.fadeIn(child, widgetState.alpha)
             child.visibility = if (widgetState.gone || widgetState.alpha == 0.0f) {