Fixed a bug with notification clipping

The clip rect was not correctly set for a view which
was fading out leading to some overdraw.
It also fixes a bug where the alpha was not applied when
made invisible.

Bug: 16077953
Change-Id: I4c26aee88c5c87147df31ec7fb413bc63cd2625c

4 files changed, 26 insertions, 21 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationBackgroundView.java b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationBackgroundView.java
index 5db680a..0fc46e9 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationBackgroundView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationBackgroundView.java
@@ -23,9 +23,7 @@ import android.graphics.PorterDuff;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.RippleDrawable;
 import android.util.AttributeSet;
-import android.view.MotionEvent;
 import android.view.View;
-import com.android.systemui.R;
 
 /**
  * A view that can be used for both the dimmed and normal background of an notification.
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
index 853628e..ddc4251 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
@@ -200,15 +200,25 @@ public class StackScrollAlgorithm {
             // apply clipping and shadow
             float newNotificationEnd = newYTranslation + newHeight;
 
-            // In the unlocked shade we have to clip a little bit higher because of the rounded
-            // corners of the notifications.
-            float clippingCorrection = state.dimmed ? 0 : mRoundedRectCornerRadius * state.scale;
-
-            // When the previous notification is swiped, we don't clip the content to the
-            // bottom of it.
-            float clipHeight = previousNotificationIsSwiped
-                    ? newHeight
-                    : newNotificationEnd - (previousNotificationEnd - clippingCorrection);
+            float clipHeight;
+            if (previousNotificationIsSwiped) {
+                // When the previous notification is swiped, we don't clip the content to the
+                // bottom of it.
+                clipHeight = newHeight;
+            } else {
+                clipHeight = newNotificationEnd - previousNotificationEnd;
+                clipHeight = Math.max(0.0f, clipHeight);
+                if (clipHeight != 0.0f) {
+
+                    // In the unlocked shade we have to clip a little bit higher because of the rounded
+                    // corners of the notifications, but only if we are not fully overlapped by
+                    // the top card.
+                    float clippingCorrection = state.dimmed
+                            ? 0
+                            : mRoundedRectCornerRadius * state.scale;
+                    clipHeight += clippingCorrection;
+                }
+            }
 
             updateChildClippingAndBackground(state, newHeight, clipHeight,
                     newHeight - (previousNotificationStart - newYTranslation));
@@ -669,7 +679,11 @@ public class StackScrollAlgorithm {
             StackScrollState.ViewState childViewState = resultState.getViewStateForView(child);
             if (i < algorithmState.itemsInTopStack) {
                 float stackIndex = algorithmState.itemsInTopStack - i;
-                stackIndex = Math.min(stackIndex, MAX_ITEMS_IN_TOP_STACK + 2);
+
+                // Ensure that the topmost item is a little bit higher than the rest when fully
+                // scrolled, to avoid drawing errors when swiping it out
+                float max = MAX_ITEMS_IN_TOP_STACK + (i == 0 ? 2.5f : 2);
+                stackIndex = Math.min(stackIndex, max);
                 if (i == 0 && algorithmState.itemsInTopStack < 2.0f) {
 
                     // We only have the top item and an additional item in the top stack,
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollState.java b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollState.java
index 0967ecd..026c2f3 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollState.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollState.java
@@ -119,9 +119,7 @@ public class StackScrollState {
                     }
 
                     // apply alpha
-                    if (!becomesInvisible) {
-                        child.setAlpha(newAlpha);
-                    }
+                    child.setAlpha(newAlpha);
                 }
 
                 // apply visibility
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackStateAnimator.java b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackStateAnimator.java
index 433357e..674642b 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackStateAnimator.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackStateAnimator.java
@@ -477,6 +477,7 @@ public class StackStateAnimator {
                 if (newEndValue == 0 && !mWasCancelled) {
                     child.setVisibility(View.INVISIBLE);
                 }
+                // remove the tag when the animation is finished
                 child.setTag(TAG_ANIMATOR_ALPHA, null);
                 child.setTag(TAG_START_ALPHA, null);
                 child.setTag(TAG_END_ALPHA, null);
@@ -498,13 +499,7 @@ public class StackStateAnimator {
             animator.setStartDelay(delay);
         }
         animator.addListener(getGlobalAnimationFinishedListener());
-        // remove the tag when the animation is finished
-        animator.addListener(new AnimatorListenerAdapter() {
-            @Override
-            public void onAnimationEnd(Animator animation) {
 
-            }
-        });
         startAnimator(animator);
         child.setTag(TAG_ANIMATOR_ALPHA, animator);
         child.setTag(TAG_START_ALPHA, child.getAlpha());