From d7f302fb4e76742772902e89c9d8a483b5778afa Mon Sep 17 00:00:00 2001
From: Sunny Shao <sunnyshao@google.com>
Date: Thu, 11 Nov 2021 15:10:59 +0800
Subject: [PATCH] Fix suw display size flicker problem

- Swipe the preview area will invoke the OnGlobalLayoutListener.
- Sometime it cause a flicker when scroll view scrolling up and
  preivew area swiping.
- It is no need to scroll up if the height of scroll view does not change.

Fixes: 205918748
Test: manual test
Change-Id: I8ed5454d32f0cf2a7bc3bac45c7aa054ce929c4b
---
 .../AccessibilityScreenSizeForSetupWizardActivity.java     | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/com/android/settings/accessibility/AccessibilityScreenSizeForSetupWizardActivity.java b/src/com/android/settings/accessibility/AccessibilityScreenSizeForSetupWizardActivity.java
index 7894c6e2789..10a0bce5c5a 100644
--- a/src/com/android/settings/accessibility/AccessibilityScreenSizeForSetupWizardActivity.java
+++ b/src/com/android/settings/accessibility/AccessibilityScreenSizeForSetupWizardActivity.java
@@ -63,6 +63,9 @@ public class AccessibilityScreenSizeForSetupWizardActivity extends InstrumentedA
         int SCREEN_SIZE = 2;
     }
 
+    // Keep the last height of the scroll view in the {@link GlifLayout}
+    private int mLastScrollViewHeight;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -143,11 +146,13 @@ public class AccessibilityScreenSizeForSetupWizardActivity extends InstrumentedA
      * Scrolls to bottom while {@link ScrollView} layout changed.
      */
     private void scrollToBottom() {
+        mLastScrollViewHeight = 0;
         final GlifLayout layout = findViewById(R.id.setup_wizard_layout);
         final ScrollView scrollView = layout.getScrollView();
         scrollView.getViewTreeObserver().addOnGlobalLayoutListener(() -> {
             final int scrollViewHeight = scrollView.getHeight();
-            if (scrollViewHeight > 0) {
+            if (scrollViewHeight > 0 && scrollViewHeight != mLastScrollViewHeight) {
+                mLastScrollViewHeight = scrollViewHeight;
                 scrollView.post(() -> {
                     // Here is no need to show the scrolling animation. So disabled first and
                     // then enabled it after scrolling finished.