Add alpha support to Insets API

All insets side may want to animate with transparency with or without
insets. This change allows any side to do that.
Also, this CL adds fade to IME when its not controlled by app.
This tries to replicate original IME animation.

Bug: 111084606
Test: Manually using test app.

Change-Id: I1ecd4715336a58cd904b2898bb36462e5ce2b6ab

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 */));
             }