From 648a02048025641b7068ac301611fad52b806838 Mon Sep 17 00:00:00 2001
From: Matt Pietal <mpietal@google.com>
Date: Wed, 20 Oct 2021 11:30:19 -0400
Subject: [PATCH] Don't register multiple predraw listeners

Also make sure they are removed properly when the view becomes
detached.

Fixes: 203257107
Test: atest KeyguardClockSwitchControllerTest

Change-Id: Ied4d4e7774d15af71648b188ac723c9c7635f506
---
 .../android/keyguard/KeyguardClockSwitch.java | 25 ++++++++++++-------
 .../KeyguardClockSwitchController.java        |  1 +
 .../KeyguardClockSwitchControllerTest.java    |  2 +-
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
index 6fd0c821bad1e..3d4e896178f6f 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
@@ -89,6 +89,7 @@ public class KeyguardClockSwitch extends RelativeLayout {
 
     private int mClockSwitchYAmount;
     @VisibleForTesting boolean mChildrenAreLaidOut = false;
+    private OnPreDrawListener mPreDrawListener;
 
     public KeyguardClockSwitch(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -284,15 +285,14 @@ public class KeyguardClockSwitch extends RelativeLayout {
         if (mChildrenAreLaidOut) {
             animateClockChange(clockSize == LARGE);
             mDisplayedClockSize = clockSize;
-        } else {
-            getViewTreeObserver().addOnPreDrawListener(new OnPreDrawListener() {
-                @Override
-                public boolean onPreDraw() {
-                    switchToClock(clockSize);
-                    getViewTreeObserver().removeOnPreDrawListener(this);
-                    return true;
-                }
-            });
+        } else if (mPreDrawListener == null) {
+            mPreDrawListener = () -> {
+                switchToClock(clockSize);
+                getViewTreeObserver().removeOnPreDrawListener(mPreDrawListener);
+                mPreDrawListener = null;
+                return true;
+            };
+            getViewTreeObserver().addOnPreDrawListener(mPreDrawListener);
         }
         return true;
     }
@@ -303,6 +303,13 @@ public class KeyguardClockSwitch extends RelativeLayout {
         mChildrenAreLaidOut = true;
     }
 
+    void onViewDetached() {
+        if (mPreDrawListener != null) {
+            getViewTreeObserver().removeOnPreDrawListener(mPreDrawListener);
+            mPreDrawListener = null;
+        }
+    }
+
     public Paint getPaint() {
         return mClockView.getPaint();
     }
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
index 01976b41a4b29..1931c0a1645ca 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
@@ -238,6 +238,7 @@ public class KeyguardClockSwitchController extends ViewController<KeyguardClockS
         }
         mColorExtractor.removeOnColorsChangedListener(mColorsListener);
         mView.setClockPlugin(null, mStatusBarStateController.getState());
+        mView.onViewDetached();
     }
 
     /**
diff --git a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
index fe0a2a4bbb145..5e0f427800fc2 100644
--- a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
+++ b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
@@ -194,7 +194,7 @@ public class KeyguardClockSwitchControllerTest extends SysuiTestCase {
         verifyAttachment(times(1));
 
         listenerArgumentCaptor.getValue().onViewDetachedFromWindow(mView);
-
+        verify(mView).onViewDetached();
         verify(mColorExtractor).removeOnColorsChangedListener(
                 any(ColorExtractor.OnColorsChangedListener.class));
     }