From 6149641c1e50313ea874ad262cbe956d37b92541 Mon Sep 17 00:00:00 2001
From: Jeff Chang <chengjeff@google.com>
Date: Sun, 19 Mar 2023 17:24:44 +0800
Subject: [PATCH] Update the split layout while density changed

According to mDividerSnapAlgorithm, the density change results in the
position of the driver bar changed, but the split layout is changed
only in the legacy transition environment. This CL updates the split
layout when the display density changed.

Bug: 273430199
Test: atest SplitLayoutTests
      atest StageCoordinatorTests
Change-Id: I767c499494c3498de36c007c7d3f1a0c275f776b
---
 .../com/android/wm/shell/common/split/SplitLayout.java    | 4 ++++
 .../android/wm/shell/splitscreen/StageCoordinator.java    | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitLayout.java b/libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitLayout.java
index 2832c553c20c8..9a2ec15238a76 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitLayout.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitLayout.java
@@ -717,6 +717,10 @@ public final class SplitLayout implements DisplayInsetsController.OnInsetsChange
         return bounds.width() > bounds.height();
     }
 
+    public boolean isDensityChanged(int densityDpi) {
+        return mDensity != densityDpi;
+    }
+
     /**
      * Return if this layout is landscape.
      */
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
index 749549d1ca557..ef0d3e61a518f 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
@@ -2183,6 +2183,14 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
             return;
         }
         mDisplayLayout.set(mDisplayController.getDisplayLayout(displayId));
+
+        if (mSplitLayout != null && mSplitLayout.isDensityChanged(newConfig.densityDpi)
+                && mMainStage.isActive()
+                && mSplitLayout.updateConfiguration(newConfig)
+                && ENABLE_SHELL_TRANSITIONS) {
+            mSplitLayout.update(null /* t */);
+            onLayoutSizeChanged(mSplitLayout);
+        }
     }
 
     void updateSurfaces(SurfaceControl.Transaction transaction) {