[flexiglass] Update NSSL stack heights, when maxNotifications changes

AmbientState#mStackEndHeight depends on NSSL#mMaxDisplayedNotifications,
so we need to recalculate the stack end height, whenever the number of  max
displayed notifications changes.

Fixes: 365727076
Test: receive Notifications on the LS, check whether there is enough space
to be displayed
Flag: com.android.systemui.scene_container

Change-Id: Ia67a244b4c229d979718af528a1149f41eb8eee3

2 files changed, 38 insertions, 2 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java
index b51ec782f183..87b16efc64fc 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java
@@ -5351,7 +5351,12 @@ public class NotificationStackScrollLayout
     public void setMaxDisplayedNotifications(int maxDisplayedNotifications) {
         if (mMaxDisplayedNotifications != maxDisplayedNotifications) {
             mMaxDisplayedNotifications = maxDisplayedNotifications;
-            updateContentHeight();
+            if (SceneContainerFlag.isEnabled()) {
+                updateIntrinsicStackHeight();
+                updateStackEndHeightAndStackHeight(mAmbientState.getExpansionFraction());
+            } else {
+                updateContentHeight();
+            }
             notifyHeightChangeListener(mShelf);
         }
     }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayoutTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayoutTest.java
index eea929da83ce..fdfc25390a3f 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayoutTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayoutTest.java
@@ -1218,7 +1218,38 @@ public class NotificationStackScrollLayoutTest extends SysuiTestCase {
     }
 
     @Test
-    @DisableSceneContainer // TODO(b/312473478): address disabled test
+    @EnableSceneContainer
+    public void testSetMaxDisplayedNotifications_updatesStackHeight() {
+        int fullStackHeight = 300;
+        int limitedStackHeight = 100;
+        int maxNotifs = 2; // any non-zero limit
+        float stackTop = 100;
+        float stackCutoff = 1100;
+        float stackViewPortHeight = stackCutoff - stackTop;
+        mStackScroller.setStackTop(stackTop);
+        mStackScroller.setStackCutoff(stackCutoff);
+        when(mStackSizeCalculator.computeHeight(eq(mStackScroller), eq(-1), anyFloat()))
+                .thenReturn((float) fullStackHeight);
+        when(mStackSizeCalculator.computeHeight(eq(mStackScroller), eq(maxNotifs), anyFloat()))
+                .thenReturn((float) limitedStackHeight);
+
+        // When we set a limit on max displayed notifications
+        mStackScroller.setMaxDisplayedNotifications(maxNotifs);
+
+        // Then
+        assertThat(mStackScroller.getIntrinsicStackHeight()).isEqualTo(limitedStackHeight);
+        assertThat(mAmbientState.getStackEndHeight()).isEqualTo(limitedStackHeight);
+
+        // When there is no limit on max displayed notifications
+        mStackScroller.setMaxDisplayedNotifications(-1);
+
+        // Then
+        assertThat(mStackScroller.getIntrinsicStackHeight()).isEqualTo(fullStackHeight);
+        assertThat(mAmbientState.getStackEndHeight()).isEqualTo(stackViewPortHeight);
+    }
+
+    @Test
+    @DisableSceneContainer
     public void testSetMaxDisplayedNotifications_notifiesListeners() {
         ExpandableView.OnHeightChangedListener listener =
                 mock(ExpandableView.OnHeightChangedListener.class);