From e6df133d98085a6d795d453f9eff53a9f46a3c3f Mon Sep 17 00:00:00 2001
From: Jeff DeCew <jeffdq@google.com>
Date: Thu, 1 Apr 2021 15:39:14 -0400
Subject: [PATCH] Remove a bit of animation clutter from group update cascades.

Bug: 180625950
Test: manual testing with notify app
Change-Id: Ia78737442b72e8a3b1a8d44f832a0aac044f174e
---
 .../SystemUI/src/com/android/systemui/Interpolators.java  | 1 +
 .../notification/row/ActivatableNotificationView.java     | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/packages/SystemUI/src/com/android/systemui/Interpolators.java b/packages/SystemUI/src/com/android/systemui/Interpolators.java
index 2eba9521b9e7a..c23bcb8dcbb0d 100644
--- a/packages/SystemUI/src/com/android/systemui/Interpolators.java
+++ b/packages/SystemUI/src/com/android/systemui/Interpolators.java
@@ -40,6 +40,7 @@ public class Interpolators {
             new PathInterpolator(0.8f, 0f, 0.6f, 1f);
     public static final Interpolator FAST_OUT_LINEAR_IN = new PathInterpolator(0.4f, 0f, 1f, 1f);
     public static final Interpolator LINEAR_OUT_SLOW_IN = new PathInterpolator(0f, 0f, 0.2f, 1f);
+    public static final Interpolator SLOW_OUT_LINEAR_IN = new PathInterpolator(0.8f, 0f, 1f, 1f);
     public static final Interpolator ALPHA_IN = new PathInterpolator(0.4f, 0f, 1f, 1f);
     public static final Interpolator ALPHA_OUT = new PathInterpolator(0f, 0f, 0.8f, 1f);
     public static final Interpolator LINEAR = new LinearInterpolator();
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ActivatableNotificationView.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ActivatableNotificationView.java
index 18e5ead7fbb8f..17f70cb082185 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ActivatableNotificationView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ActivatableNotificationView.java
@@ -720,6 +720,10 @@ public abstract class ActivatableNotificationView extends ExpandableOutlineView
             mCurrentAppearInterpolator = mSlowOutFastInInterpolator;
             mCurrentAlphaInterpolator = Interpolators.LINEAR_OUT_SLOW_IN;
             targetValue = 1.0f;
+            if (!mIsHeadsUpAnimation && isChildInGroup()) {
+                // slower fade in of children to avoid visibly overlapping with other children
+                mCurrentAlphaInterpolator = Interpolators.SLOW_OUT_LINEAR_IN;
+            }
         } else {
             mCurrentAppearInterpolator = Interpolators.FAST_OUT_SLOW_IN;
             mCurrentAlphaInterpolator = mSlowOutLinearInInterpolator;
@@ -819,6 +823,10 @@ public abstract class ActivatableNotificationView extends ExpandableOutlineView
         if (mIsHeadsUpAnimation && !mIsAppearing) {
             startWidthFraction = 0;
         }
+        if (mIsAppearing && !mIsHeadsUpAnimation && isChildInGroup()) {
+            // Children in a group (when not heads up) should simply fade in.
+            startWidthFraction = 1;
+        }
         float width = MathUtils.lerp(startWidthFraction, 1.0f, 1.0f - widthFraction)
                         * getWidth();
         float left;