1 files changed, 28 insertions, 8 deletions

diff --git a/core/java/android/view/InsetsAnimationControlImpl.java b/core/java/android/view/InsetsAnimationControlImpl.java
index 7ea4f3062e21..cdfd397a732a 100644
--- a/core/java/android/view/InsetsAnimationControlImpl.java
+++ b/core/java/android/view/InsetsAnimationControlImpl.java
@@ -68,22 +68,26 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
     private final InsetsController mController;
     private final WindowInsetsAnimationCallback.InsetsAnimation mAnimation;
     private final Rect mFrame;
+    private final boolean mFade;
     private Insets mCurrentInsets;
     private Insets mPendingInsets;
     private float mPendingFraction;
     private boolean mFinished;
     private boolean mCancelled;
     private boolean mShownOnFinish;
+    private float mCurrentAlpha;
+    private float mPendingAlpha;
 
     @VisibleForTesting
     public InsetsAnimationControlImpl(SparseArray<InsetsSourceConsumer> consumers, Rect frame,
             InsetsState state, WindowInsetsAnimationControlListener listener,
             @InsetsType int types,
             Supplier<SyncRtSurfaceTransactionApplier> transactionApplierSupplier,
-            InsetsController controller, long durationMs) {
+            InsetsController controller, long durationMs, boolean fade) {
         mConsumers = consumers;
         mListener = listener;
         mTypes = types;
+        mFade = fade;
         mTransactionApplierSupplier = transactionApplierSupplier;
         mController = controller;
         mInitialInsetsState = new InsetsState(state, true /* copySources */);
@@ -100,6 +104,7 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
 
         mAnimation = new WindowInsetsAnimationCallback.InsetsAnimation(mTypes,
                 InsetsController.INTERPOLATOR, durationMs);
+        mAnimation.setAlpha(getCurrentAlpha());
         mController.dispatchAnimationStarted(mAnimation,
                 new AnimationBounds(mHiddenInsets, mShownInsets));
     }
@@ -120,6 +125,11 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
     }
 
     @Override
+    public float getCurrentAlpha() {
+        return mCurrentAlpha;
+    }
+
+    @Override
     @InsetsType public int getTypes() {
         return mTypes;
     }
@@ -136,6 +146,7 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
         }
         mPendingFraction = sanitize(fraction);
         mPendingInsets = sanitize(insets);
+        mPendingAlpha = 1 - sanitize(alpha);
         mController.scheduleApplyChangeInsets();
     }
 
@@ -148,17 +159,24 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
             return false;
         }
         final Insets offset = Insets.subtract(mShownInsets, mPendingInsets);
+        final Float alphaOffset = 1 - mPendingAlpha;
         ArrayList<SurfaceParams> params = new ArrayList<>();
-        updateLeashesForSide(ISIDE_LEFT, offset.left, mPendingInsets.left, params, state);
-        updateLeashesForSide(ISIDE_TOP, offset.top, mPendingInsets.top, params, state);
-        updateLeashesForSide(ISIDE_RIGHT, offset.right, mPendingInsets.right, params, state);
-        updateLeashesForSide(ISIDE_BOTTOM, offset.bottom, mPendingInsets.bottom, params, state);
-        updateLeashesForSide(ISIDE_FLOATING, 0 /* offset */, 0 /* inset */, params, state);
+        updateLeashesForSide(ISIDE_LEFT, offset.left, mShownInsets.left, mPendingInsets.left,
+                params, state, alphaOffset);
+        updateLeashesForSide(ISIDE_TOP, offset.top, mShownInsets.top, mPendingInsets.top, params,
+                state, alphaOffset);
+        updateLeashesForSide(ISIDE_RIGHT, offset.right, mShownInsets.right, mPendingInsets.right,
+                params, state, alphaOffset);
+        updateLeashesForSide(ISIDE_BOTTOM, offset.bottom, mShownInsets.bottom,
+                mPendingInsets.bottom, params, state, alphaOffset);
+        updateLeashesForSide(ISIDE_FLOATING, 0 /* offset */, 0 /* inset */, 0 /* maxInset */,
+                params, state, alphaOffset);
 
         SyncRtSurfaceTransactionApplier applier = mTransactionApplierSupplier.get();
         applier.scheduleApply(params.toArray(new SurfaceParams[params.size()]));
         mCurrentInsets = mPendingInsets;
         mAnimation.setFraction(mPendingFraction);
+        mCurrentAlpha = 1 - alphaOffset;
         if (mFinished) {
             mController.notifyFinished(this, mShownOnFinish);
         }
@@ -233,7 +251,7 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
     }
 
     private void updateLeashesForSide(@InternalInsetsSide int side, int offset, int inset,
-            ArrayList<SurfaceParams> surfaceParams, InsetsState state) {
+            int maxInset, ArrayList<SurfaceParams> surfaceParams, InsetsState state, Float alpha) {
         ArraySet<InsetsSourceConsumer> items = mSideSourceMap.get(side);
         if (items == null) {
             return;
@@ -257,7 +275,9 @@ public class InsetsAnimationControlImpl implements WindowInsetsAnimationControll
 
             // If the system is controlling the insets source, the leash can be null.
             if (leash != null) {
-                surfaceParams.add(new SurfaceParams(leash, 1f /* alpha */, mTmpMatrix,
+                // TODO: use a better interpolation for fade.
+                alpha = mFade ? ((float) maxInset / inset * 0.3f + 0.7f) : alpha;
+                surfaceParams.add(new SurfaceParams(leash, alpha, mTmpMatrix,
                         null /* windowCrop */, 0 /* layer */, 0f /* cornerRadius*/,
                         side == ISIDE_FLOATING ? consumer.isVisible() : inset != 0 /* visible */));
             }