From 2e4f9fe61b9a2ba445dc49ad4d2cf11ac079e101 Mon Sep 17 00:00:00 2001
From: Leo Hsu <leohsu@google.com>
Date: Fri, 20 Apr 2018 10:40:08 +0800
Subject: [PATCH] Usage graphs support RTL style.

Flips the canvas horizontally before drawing paths under RTL mode.

Bug: 78008951
Test: manually verified graphs of wifi data usage, app data usage, and
battery usage.

Change-Id: I79286e9f3f98632e3a9710d42c3e197231a14c39
---
 res/layout/usage_view.xml                       | 3 +--
 src/com/android/settings/widget/UsageGraph.java | 6 ++++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/res/layout/usage_view.xml b/res/layout/usage_view.xml
index 16b4916eff5..c24f28974ac 100644
--- a/res/layout/usage_view.xml
+++ b/res/layout/usage_view.xml
@@ -80,8 +80,7 @@
             android:layout_width="0dp"
             android:layout_height="wrap_content"
             android:layout_weight="1"
-            android:orientation="horizontal"
-            android:layoutDirection="ltr">
+            android:orientation="horizontal">
             <include android:id="@+id/label_start"
                      layout="@layout/usage_side_label" />
 
diff --git a/src/com/android/settings/widget/UsageGraph.java b/src/com/android/settings/widget/UsageGraph.java
index da61607278f..7238e5de128 100644
--- a/src/com/android/settings/widget/UsageGraph.java
+++ b/src/com/android/settings/widget/UsageGraph.java
@@ -255,9 +255,15 @@ public class UsageGraph extends View {
             return;
         }
 
+        canvas.save();
+        if (getLayoutDirection() == LAYOUT_DIRECTION_RTL) {
+            // Flip the canvas along the y-axis of the center of itself before drawing paths.
+            canvas.scale(-1, 1, canvas.getWidth() * 0.5f, 0);
+        }
         drawLinePath(canvas, mLocalProjectedPaths, mDottedPaint);
         drawFilledPath(canvas, mLocalPaths, mFillPaint);
         drawLinePath(canvas, mLocalPaths, mLinePaint);
+        canvas.restore();
         BatteryUtils.logRuntime(LOG_TAG, "onDraw", startTime);
     }