Animate ActivityEmbedding transition with Shell Transition

Make a copy of TaskFragmentAnimation* to ActivityEmbeddingAnimation*
to fit into Shell transition model.

Bug: 207070762
Test: atest WMShellUnitTests:ActivityEmbeddingControllerTests
Test: atest WMShellUnitTests:ActivityEmbeddingAnimationRunnerTests
Change-Id: I44118e1415f85bcd49fa77bff10c67094ec9cad5

libs/WindowManager/Shell/src/com/android/wm/shell/activityembedding/ActivityEmbeddingAnimationAdapter.java

@@ -0,0 +1,234 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.activityembedding;
+
+import static android.graphics.Matrix.MSCALE_X;
+import static android.graphics.Matrix.MTRANS_X;
+import static android.graphics.Matrix.MTRANS_Y;
+
+import android.annotation.CallSuper;
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.view.Choreographer;
+import android.view.SurfaceControl;
+import android.view.animation.Animation;
+import android.view.animation.Transformation;
+import android.window.TransitionInfo;
+
+import androidx.annotation.NonNull;
+
+/**
+ * Wrapper to handle the ActivityEmbedding animation update in one
+ * {@link SurfaceControl.Transaction}.
+ */
+class ActivityEmbeddingAnimationAdapter {
+
+    /**
+     * If {@link #mOverrideLayer} is set to this value, we don't want to override the surface layer.
+     */
+    private static final int LAYER_NO_OVERRIDE = -1;
+
+    final Animation mAnimation;
+    final TransitionInfo.Change mChange;
+    final SurfaceControl mLeash;
+
+    final Transformation mTransformation = new Transformation();
+    final float[] mMatrix = new float[9];
+    final float[] mVecs = new float[4];
+    final Rect mRect = new Rect();
+    private boolean mIsFirstFrame = true;
+    private int mOverrideLayer = LAYER_NO_OVERRIDE;
+
+    ActivityEmbeddingAnimationAdapter(@NonNull Animation animation,
+            @NonNull TransitionInfo.Change change) {
+        this(animation, change, change.getLeash());
+    }
+
+    /**
+     * @param leash the surface to animate, which is not necessary the same as
+     * {@link TransitionInfo.Change#getLeash()}, it can be a screenshot for example.
+     */
+    ActivityEmbeddingAnimationAdapter(@NonNull Animation animation,
+            @NonNull TransitionInfo.Change change, @NonNull SurfaceControl leash) {
+        mAnimation = animation;
+        mChange = change;
+        mLeash = leash;
+    }
+
+    /**
+     * Surface layer to be set at the first frame of the animation. We will not set the layer if it
+     * is set to {@link #LAYER_NO_OVERRIDE}.
+     */
+    final void overrideLayer(int layer) {
+        mOverrideLayer = layer;
+    }
+
+    /** Called on frame update. */
+    final void onAnimationUpdate(@NonNull SurfaceControl.Transaction t, long currentPlayTime) {
+        if (mIsFirstFrame) {
+            t.show(mLeash);
+            if (mOverrideLayer != LAYER_NO_OVERRIDE) {
+                t.setLayer(mLeash, mOverrideLayer);
+            }
+            mIsFirstFrame = false;
+        }
+
+        // Extract the transformation to the current time.
+        mAnimation.getTransformation(Math.min(currentPlayTime, mAnimation.getDuration()),
+                mTransformation);
+        t.setFrameTimelineVsync(Choreographer.getInstance().getVsyncId());
+        onAnimationUpdateInner(t);
+    }
+
+    /** To be overridden by subclasses to adjust the animation surface change. */
+    void onAnimationUpdateInner(@NonNull SurfaceControl.Transaction t) {
+        final Point offset = mChange.getEndRelOffset();
+        mTransformation.getMatrix().postTranslate(offset.x, offset.y);
+        t.setMatrix(mLeash, mTransformation.getMatrix(), mMatrix);
+        t.setAlpha(mLeash, mTransformation.getAlpha());
+        // Get current animation position.
+        final int positionX = Math.round(mMatrix[MTRANS_X]);
+        final int positionY = Math.round(mMatrix[MTRANS_Y]);
+        // The exiting surface starts at position: Change#getEndRelOffset() and moves with
+        // positionX varying. Offset our crop region by the amount we have slided so crop
+        // regions stays exactly on the original container in split.
+        final int cropOffsetX = offset.x - positionX;
+        final int cropOffsetY = offset.y - positionY;
+        final Rect cropRect = new Rect();
+        cropRect.set(mChange.getEndAbsBounds());
+        // Because window crop uses absolute position.
+        cropRect.offsetTo(0, 0);
+        cropRect.offset(cropOffsetX, cropOffsetY);
+        t.setCrop(mLeash, cropRect);
+    }
+
+    /** Called after animation finished. */
+    @CallSuper
+    void onAnimationEnd(@NonNull SurfaceControl.Transaction t) {
+        onAnimationUpdate(t, mAnimation.getDuration());
+    }
+
+    final long getDurationHint() {
+        return mAnimation.computeDurationHint();
+    }
+
+    /**
+     * Should be used when the {@link TransitionInfo.Change} is in split with others, and wants to
+     * animate together as one. This adapter will offset the animation leash to make the animate of
+     * two windows look like a single window.
+     */
+    static class SplitAdapter extends ActivityEmbeddingAnimationAdapter {
+        private final boolean mIsLeftHalf;
+        private final int mWholeAnimationWidth;
+
+        /**
+         * @param isLeftHalf whether this is the left half of the animation.
+         * @param wholeAnimationWidth the whole animation windows width.
+         */
+        SplitAdapter(@NonNull Animation animation, @NonNull TransitionInfo.Change change,
+                boolean isLeftHalf, int wholeAnimationWidth) {
+            super(animation, change);
+            mIsLeftHalf = isLeftHalf;
+            mWholeAnimationWidth = wholeAnimationWidth;
+            if (wholeAnimationWidth == 0) {
+                throw new IllegalArgumentException("SplitAdapter must provide wholeAnimationWidth");
+            }
+        }
+
+        @Override
+        void onAnimationUpdateInner(@NonNull SurfaceControl.Transaction t) {
+            final Point offset = mChange.getEndRelOffset();
+            float posX = offset.x;
+            final float posY = offset.y;
+            // This window is half of the whole animation window. Offset left/right to make it
+            // look as one with the other half.
+            mTransformation.getMatrix().getValues(mMatrix);
+            final int changeWidth = mChange.getEndAbsBounds().width();
+            final float scaleX = mMatrix[MSCALE_X];
+            final float totalOffset = mWholeAnimationWidth * (1 - scaleX) / 2;
+            final float curOffset = changeWidth * (1 - scaleX) / 2;
+            final float offsetDiff = totalOffset - curOffset;
+            if (mIsLeftHalf) {
+                posX += offsetDiff;
+            } else {
+                posX -= offsetDiff;
+            }
+            mTransformation.getMatrix().postTranslate(posX, posY);
+            t.setMatrix(mLeash, mTransformation.getMatrix(), mMatrix);
+            t.setAlpha(mLeash, mTransformation.getAlpha());
+        }
+    }
+
+    /**
+     * Should be used for the animation of the snapshot of a {@link TransitionInfo.Change} that has
+     * size change.
+     */
+    static class SnapshotAdapter extends ActivityEmbeddingAnimationAdapter {
+
+        SnapshotAdapter(@NonNull Animation animation, @NonNull TransitionInfo.Change change,
+                @NonNull SurfaceControl snapshotLeash) {
+            super(animation, change, snapshotLeash);
+        }
+
+        @Override
+        void onAnimationUpdateInner(@NonNull SurfaceControl.Transaction t) {
+            // Snapshot should always be placed at the top left of the animation leash.
+            mTransformation.getMatrix().postTranslate(0, 0);
+            t.setMatrix(mLeash, mTransformation.getMatrix(), mMatrix);
+            t.setAlpha(mLeash, mTransformation.getAlpha());
+        }
+
+        @Override
+        void onAnimationEnd(@NonNull SurfaceControl.Transaction t) {
+            super.onAnimationEnd(t);
+            // Remove the screenshot leash after animation is finished.
+            t.remove(mLeash);
+        }
+    }
+
+    /**
+     * Should be used for the animation of the {@link TransitionInfo.Change} that has size change.
+     */
+    static class BoundsChangeAdapter extends ActivityEmbeddingAnimationAdapter {
+
+        BoundsChangeAdapter(@NonNull Animation animation, @NonNull TransitionInfo.Change change) {
+            super(animation, change);
+        }
+
+        @Override
+        void onAnimationUpdateInner(@NonNull SurfaceControl.Transaction t) {
+            final Point offset = mChange.getEndRelOffset();
+            mTransformation.getMatrix().postTranslate(offset.x, offset.y);
+            t.setMatrix(mLeash, mTransformation.getMatrix(), mMatrix);
+            t.setAlpha(mLeash, mTransformation.getAlpha());
+
+            // The following applies an inverse scale to the clip-rect so that it crops "after" the
+            // scale instead of before.
+            mVecs[1] = mVecs[2] = 0;
+            mVecs[0] = mVecs[3] = 1;
+            mTransformation.getMatrix().mapVectors(mVecs);
+            mVecs[0] = 1.f / mVecs[0];
+            mVecs[3] = 1.f / mVecs[3];
+            final Rect clipRect = mTransformation.getClipRect();
+            mRect.left = (int) (clipRect.left * mVecs[0] + 0.5f);
+            mRect.right = (int) (clipRect.right * mVecs[0] + 0.5f);
+            mRect.top = (int) (clipRect.top * mVecs[3] + 0.5f);
+            mRect.bottom = (int) (clipRect.bottom * mVecs[3] + 0.5f);
+            t.setCrop(mLeash, mRect);
+        }
+    }
+}

libs/WindowManager/Shell/src/com/android/wm/shell/activityembedding/ActivityEmbeddingAnimationRunner.java

@@ -0,0 +1,290 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.activityembedding;
+
+import static android.view.WindowManager.TRANSIT_CHANGE;
+import static android.view.WindowManagerPolicyConstants.TYPE_LAYER_OFFSET;
+
+import android.animation.Animator;
+import android.animation.ValueAnimator;
+import android.content.Context;
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.os.IBinder;
+import android.util.Log;
+import android.view.SurfaceControl;
+import android.view.animation.Animation;
+import android.window.TransitionInfo;
+import android.window.WindowContainerToken;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.wm.shell.common.ScreenshotUtils;
+import com.android.wm.shell.transition.Transitions;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.BiFunction;
+
+/** To run the ActivityEmbedding animations. */
+class ActivityEmbeddingAnimationRunner {
+
+    private static final String TAG = "ActivityEmbeddingAnimR";
+
+    private final ActivityEmbeddingController mController;
+    @VisibleForTesting
+    final ActivityEmbeddingAnimationSpec mAnimationSpec;
+
+    ActivityEmbeddingAnimationRunner(@NonNull Context context,
+            @NonNull ActivityEmbeddingController controller) {
+        mController = controller;
+        mAnimationSpec = new ActivityEmbeddingAnimationSpec(context);
+    }
+
+    /** Creates and starts animation for ActivityEmbedding transition. */
+    void startAnimation(@NonNull IBinder transition, @NonNull TransitionInfo info,
+            @NonNull SurfaceControl.Transaction startTransaction,
+            @NonNull SurfaceControl.Transaction finishTransaction) {
+        final Animator animator = createAnimator(info, startTransaction, finishTransaction,
+                () -> mController.onAnimationFinished(transition));
+        startTransaction.apply();
+        animator.start();
+    }
+
+    /**
+     * Sets transition animation scale settings value.
+     * @param scale The setting value of transition animation scale.
+     */
+    void setAnimScaleSetting(float scale) {
+        mAnimationSpec.setAnimScaleSetting(scale);
+    }
+
+    /** Creates the animator for the given {@link TransitionInfo}. */
+    @VisibleForTesting
+    @NonNull
+    Animator createAnimator(@NonNull TransitionInfo info,
+            @NonNull SurfaceControl.Transaction startTransaction,
+            @NonNull SurfaceControl.Transaction finishTransaction,
+            @NonNull Runnable animationFinishCallback) {
+        final List<ActivityEmbeddingAnimationAdapter> adapters =
+                createAnimationAdapters(info, startTransaction);
+        long duration = 0;
+        for (ActivityEmbeddingAnimationAdapter adapter : adapters) {
+            duration = Math.max(duration, adapter.getDurationHint());
+        }
+        final ValueAnimator animator = ValueAnimator.ofFloat(0, 1);
+        animator.setDuration(duration);
+        animator.addUpdateListener((anim) -> {
+            // Update all adapters in the same transaction.
+            final SurfaceControl.Transaction t = new SurfaceControl.Transaction();
+            for (ActivityEmbeddingAnimationAdapter adapter : adapters) {
+                adapter.onAnimationUpdate(t, animator.getCurrentPlayTime());
+            }
+            t.apply();
+        });
+        animator.addListener(new Animator.AnimatorListener() {
+            @Override
+            public void onAnimationStart(Animator animation) {}
+
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                final SurfaceControl.Transaction t = new SurfaceControl.Transaction();
+                for (ActivityEmbeddingAnimationAdapter adapter : adapters) {
+                    adapter.onAnimationEnd(t);
+                }
+                t.apply();
+                animationFinishCallback.run();
+            }
+
+            @Override
+            public void onAnimationCancel(Animator animation) {}
+
+            @Override
+            public void onAnimationRepeat(Animator animation) {}
+        });
+        return animator;
+    }
+
+    /**
+     * Creates list of {@link ActivityEmbeddingAnimationAdapter} to handle animations on all window
+     * changes.
+     */
+    @NonNull
+    private List<ActivityEmbeddingAnimationAdapter> createAnimationAdapters(
+            @NonNull TransitionInfo info, @NonNull SurfaceControl.Transaction startTransaction) {
+        for (TransitionInfo.Change change : info.getChanges()) {
+            if (change.getMode() == TRANSIT_CHANGE
+                    && !change.getStartAbsBounds().equals(change.getEndAbsBounds())) {
+                return createChangeAnimationAdapters(info, startTransaction);
+            }
+        }
+        if (Transitions.isClosingType(info.getType())) {
+            return createCloseAnimationAdapters(info);
+        }
+        return createOpenAnimationAdapters(info);
+    }
+
+    @NonNull
+    private List<ActivityEmbeddingAnimationAdapter> createOpenAnimationAdapters(
+            @NonNull TransitionInfo info) {
+        return createOpenCloseAnimationAdapters(info, true /* isOpening */,
+                mAnimationSpec::loadOpenAnimation);
+    }
+
+    @NonNull
+    private List<ActivityEmbeddingAnimationAdapter> createCloseAnimationAdapters(
+            @NonNull TransitionInfo info) {
+        return createOpenCloseAnimationAdapters(info, false /* isOpening */,
+                mAnimationSpec::loadCloseAnimation);
+    }
+
+    /**
+     * Creates {@link ActivityEmbeddingAnimationAdapter} for OPEN and CLOSE types of transition.
+     * @param isOpening {@code true} for OPEN type, {@code false} for CLOSE type.
+     */
+    @NonNull
+    private List<ActivityEmbeddingAnimationAdapter> createOpenCloseAnimationAdapters(
+            @NonNull TransitionInfo info, boolean isOpening,
+            @NonNull BiFunction<TransitionInfo.Change, Rect, Animation> animationProvider) {
+        // We need to know if the change window is only a partial of the whole animation screen.
+        // If so, we will need to adjust it to make the whole animation screen looks like one.
+        final List<TransitionInfo.Change> openingChanges = new ArrayList<>();
+        final List<TransitionInfo.Change> closingChanges = new ArrayList<>();
+        final Rect openingWholeScreenBounds = new Rect();
+        final Rect closingWholeScreenBounds = new Rect();
+        for (TransitionInfo.Change change : info.getChanges()) {
+            final Rect bounds = new Rect(change.getEndAbsBounds());
+            final Point offset = change.getEndRelOffset();
+            bounds.offsetTo(offset.x, offset.y);
+            if (Transitions.isOpeningType(change.getMode())) {
+                openingChanges.add(change);
+                openingWholeScreenBounds.union(bounds);
+            } else {
+                closingChanges.add(change);
+                closingWholeScreenBounds.union(bounds);
+            }
+        }
+
+        // For OPEN transition, open windows should be above close windows.
+        // For CLOSE transition, open windows should be below close windows.
+        int offsetLayer = TYPE_LAYER_OFFSET;
+        final List<ActivityEmbeddingAnimationAdapter> adapters = new ArrayList<>();
+        for (TransitionInfo.Change change : openingChanges) {
+            final ActivityEmbeddingAnimationAdapter adapter = createOpenCloseAnimationAdapter(
+                    change, animationProvider, openingWholeScreenBounds);
+            if (isOpening) {
+                adapter.overrideLayer(offsetLayer++);
+            }
+            adapters.add(adapter);
+        }
+        for (TransitionInfo.Change change : closingChanges) {
+            final ActivityEmbeddingAnimationAdapter adapter = createOpenCloseAnimationAdapter(
+                    change, animationProvider, closingWholeScreenBounds);
+            if (!isOpening) {
+                adapter.overrideLayer(offsetLayer++);
+            }
+            adapters.add(adapter);
+        }
+        return adapters;
+    }
+
+    @NonNull
+    private ActivityEmbeddingAnimationAdapter createOpenCloseAnimationAdapter(
+            @NonNull TransitionInfo.Change change,
+            @NonNull BiFunction<TransitionInfo.Change, Rect, Animation> animationProvider,
+            @NonNull Rect wholeAnimationBounds) {
+        final Animation animation = animationProvider.apply(change, wholeAnimationBounds);
+        final Rect bounds = new Rect(change.getEndAbsBounds());
+        final Point offset = change.getEndRelOffset();
+        bounds.offsetTo(offset.x, offset.y);
+        if (bounds.left == wholeAnimationBounds.left
+                && bounds.right != wholeAnimationBounds.right) {
+            // This is the left split of the whole animation window.
+            return new ActivityEmbeddingAnimationAdapter.SplitAdapter(animation, change,
+                    true /* isLeftHalf */, wholeAnimationBounds.width());
+        } else if (bounds.left != wholeAnimationBounds.left
+                && bounds.right == wholeAnimationBounds.right) {
+            // This is the right split of the whole animation window.
+            return new ActivityEmbeddingAnimationAdapter.SplitAdapter(animation, change,
+                    false /* isLeftHalf */, wholeAnimationBounds.width());
+        }
+        // Open/close window that fills the whole animation.
+        return new ActivityEmbeddingAnimationAdapter(animation, change);
+    }
+
+    @NonNull
+    private List<ActivityEmbeddingAnimationAdapter> createChangeAnimationAdapters(
+            @NonNull TransitionInfo info, @NonNull SurfaceControl.Transaction startTransaction) {
+        final List<ActivityEmbeddingAnimationAdapter> adapters = new ArrayList<>();
+        for (TransitionInfo.Change change : info.getChanges()) {
+            if (change.getMode() == TRANSIT_CHANGE
+                    && !change.getStartAbsBounds().equals(change.getEndAbsBounds())) {
+                // This is the window with bounds change.
+                final WindowContainerToken parentToken = change.getParent();
+                final Rect parentBounds;
+                if (parentToken != null) {
+                    TransitionInfo.Change parentChange = info.getChange(parentToken);
+                    parentBounds = parentChange != null
+                            ? parentChange.getEndAbsBounds()
+                            : change.getEndAbsBounds();
+                } else {
+                    parentBounds = change.getEndAbsBounds();
+                }
+                final Animation[] animations =
+                        mAnimationSpec.createChangeBoundsChangeAnimations(change, parentBounds);
+                // Adapter for the starting screenshot leash.
+                final SurfaceControl screenshotLeash = createScreenshot(change, startTransaction);
+                if (screenshotLeash != null) {
+                    // The screenshot leash will be removed in SnapshotAdapter#onAnimationEnd
+                    adapters.add(new ActivityEmbeddingAnimationAdapter.SnapshotAdapter(
+                            animations[0], change, screenshotLeash));
+                } else {
+                    Log.e(TAG, "Failed to take screenshot for change=" + change);
+                }
+                // Adapter for the ending bounds changed leash.
+                adapters.add(new ActivityEmbeddingAnimationAdapter.BoundsChangeAdapter(
+                        animations[1], change));
+                continue;
+            }
+
+            // These are the other windows that don't have bounds change in the same transition.
+            final Animation animation;
+            if (!TransitionInfo.isIndependent(change, info)) {
+                // No-op if it will be covered by the changing parent window.
+                animation = ActivityEmbeddingAnimationSpec.createNoopAnimation(change);
+            } else if (Transitions.isClosingType(change.getMode())) {
+                animation = mAnimationSpec.createChangeBoundsCloseAnimation(change);
+            } else {
+                animation = mAnimationSpec.createChangeBoundsOpenAnimation(change);
+            }
+            adapters.add(new ActivityEmbeddingAnimationAdapter(animation, change));
+        }
+        return adapters;
+    }
+
+    /** Takes a screenshot of the given {@link TransitionInfo.Change} surface. */
+    @Nullable
+    private SurfaceControl createScreenshot(@NonNull TransitionInfo.Change change,
+            @NonNull SurfaceControl.Transaction startTransaction) {
+        final Rect cropBounds = new Rect(change.getStartAbsBounds());
+        cropBounds.offsetTo(0, 0);
+        return ScreenshotUtils.takeScreenshot(startTransaction, change.getLeash(), cropBounds,
+                Integer.MAX_VALUE);
+    }
+}

libs/WindowManager/Shell/src/com/android/wm/shell/activityembedding/ActivityEmbeddingAnimationSpec.java

@@ -0,0 +1,212 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.activityembedding;
+
+
+import android.content.Context;
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.view.animation.AlphaAnimation;
+import android.view.animation.Animation;
+import android.view.animation.AnimationSet;
+import android.view.animation.AnimationUtils;
+import android.view.animation.ClipRectAnimation;
+import android.view.animation.Interpolator;
+import android.view.animation.LinearInterpolator;
+import android.view.animation.ScaleAnimation;
+import android.view.animation.TranslateAnimation;
+import android.window.TransitionInfo;
+
+import androidx.annotation.NonNull;
+
+import com.android.internal.R;
+import com.android.internal.policy.TransitionAnimation;
+import com.android.wm.shell.transition.Transitions;
+
+/** Animation spec for ActivityEmbedding transition. */
+// TODO(b/206557124): provide an easier way to customize animation
+class ActivityEmbeddingAnimationSpec {
+
+    private static final String TAG = "ActivityEmbeddingAnimSpec";
+    private static final int CHANGE_ANIMATION_DURATION = 517;
+    private static final int CHANGE_ANIMATION_FADE_DURATION = 80;
+    private static final int CHANGE_ANIMATION_FADE_OFFSET = 30;
+
+    private final Context mContext;
+    private final TransitionAnimation mTransitionAnimation;
+    private final Interpolator mFastOutExtraSlowInInterpolator;
+    private final LinearInterpolator mLinearInterpolator;
+    private float mTransitionAnimationScaleSetting;
+
+    ActivityEmbeddingAnimationSpec(@NonNull Context context) {
+        mContext = context;
+        mTransitionAnimation = new TransitionAnimation(mContext, false /* debug */, TAG);
+        mFastOutExtraSlowInInterpolator = AnimationUtils.loadInterpolator(
+                mContext, android.R.interpolator.fast_out_extra_slow_in);
+        mLinearInterpolator = new LinearInterpolator();
+    }
+
+    /**
+     * Sets transition animation scale settings value.
+     * @param scale The setting value of transition animation scale.
+     */
+    void setAnimScaleSetting(float scale) {
+        mTransitionAnimationScaleSetting = scale;
+    }
+
+    /** For window that doesn't need to be animated. */
+    @NonNull
+    static Animation createNoopAnimation(@NonNull TransitionInfo.Change change) {
+        // Noop but just keep the window showing/hiding.
+        final float alpha = Transitions.isClosingType(change.getMode()) ? 0f : 1f;
+        return new AlphaAnimation(alpha, alpha);
+    }
+
+    /** Animation for window that is opening in a change transition. */
+    @NonNull
+    Animation createChangeBoundsOpenAnimation(@NonNull TransitionInfo.Change change) {
+        final Rect bounds = change.getEndAbsBounds();
+        final Point offset = change.getEndRelOffset();
+        // The window will be animated in from left or right depends on its position.
+        final int startLeft = offset.x == 0 ? -bounds.width() : bounds.width();
+
+        // The position should be 0-based as we will post translate in
+        // ActivityEmbeddingAnimationAdapter#onAnimationUpdate
+        final Animation animation = new TranslateAnimation(startLeft, 0, 0, 0);
+        animation.setInterpolator(mFastOutExtraSlowInInterpolator);
+        animation.setDuration(CHANGE_ANIMATION_DURATION);
+        animation.initialize(bounds.width(), bounds.height(), bounds.width(), bounds.height());
+        animation.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+        return animation;
+    }
+
+    /** Animation for window that is closing in a change transition. */
+    @NonNull
+    Animation createChangeBoundsCloseAnimation(@NonNull TransitionInfo.Change change) {
+        final Rect bounds = change.getEndAbsBounds();
+        final Point offset = change.getEndRelOffset();
+        // The window will be animated out to left or right depends on its position.
+        final int endLeft = offset.x == 0 ? -bounds.width() : bounds.width();
+
+        // The position should be 0-based as we will post translate in
+        // ActivityEmbeddingAnimationAdapter#onAnimationUpdate
+        final Animation animation = new TranslateAnimation(0, endLeft, 0, 0);
+        animation.setInterpolator(mFastOutExtraSlowInInterpolator);
+        animation.setDuration(CHANGE_ANIMATION_DURATION);
+        animation.initialize(bounds.width(), bounds.height(), bounds.width(), bounds.height());
+        animation.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+        return animation;
+    }
+
+    /**
+     * Animation for window that is changing (bounds change) in a change transition.
+     * @return the return array always has two elements. The first one is for the start leash, and
+     *         the second one is for the end leash.
+     */
+    @NonNull
+    Animation[] createChangeBoundsChangeAnimations(@NonNull TransitionInfo.Change change,
+            @NonNull Rect parentBounds) {
+        // Both start bounds and end bounds are in screen coordinates. We will post translate
+        // to the local coordinates in ActivityEmbeddingAnimationAdapter#onAnimationUpdate
+        final Rect startBounds = change.getStartAbsBounds();
+        final Rect endBounds = change.getEndAbsBounds();
+        float scaleX = ((float) startBounds.width()) / endBounds.width();
+        float scaleY = ((float) startBounds.height()) / endBounds.height();
+        // Start leash is a child of the end leash. Reverse the scale so that the start leash won't
+        // be scaled up with its parent.
+        float startScaleX = 1.f / scaleX;
+        float startScaleY = 1.f / scaleY;
+
+        // The start leash will be fade out.
+        final AnimationSet startSet = new AnimationSet(false /* shareInterpolator */);
+        final Animation startAlpha = new AlphaAnimation(1f, 0f);
+        startAlpha.setInterpolator(mLinearInterpolator);
+        startAlpha.setDuration(CHANGE_ANIMATION_FADE_DURATION);
+        startAlpha.setStartOffset(CHANGE_ANIMATION_FADE_OFFSET);
+        startSet.addAnimation(startAlpha);
+        final Animation startScale = new ScaleAnimation(startScaleX, startScaleX, startScaleY,
+                startScaleY);
+        startScale.setInterpolator(mFastOutExtraSlowInInterpolator);
+        startScale.setDuration(CHANGE_ANIMATION_DURATION);
+        startSet.addAnimation(startScale);
+        startSet.initialize(startBounds.width(), startBounds.height(), endBounds.width(),
+                endBounds.height());
+        startSet.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+
+        // The end leash will be moved into the end position while scaling.
+        final AnimationSet endSet = new AnimationSet(true /* shareInterpolator */);
+        endSet.setInterpolator(mFastOutExtraSlowInInterpolator);
+        final Animation endScale = new ScaleAnimation(scaleX, 1, scaleY, 1);
+        endScale.setDuration(CHANGE_ANIMATION_DURATION);
+        endSet.addAnimation(endScale);
+        // The position should be 0-based as we will post translate in
+        // ActivityEmbeddingAnimationAdapter#onAnimationUpdate
+        final Animation endTranslate = new TranslateAnimation(startBounds.left - endBounds.left, 0,
+                0, 0);
+        endTranslate.setDuration(CHANGE_ANIMATION_DURATION);
+        endSet.addAnimation(endTranslate);
+        // The end leash is resizing, we should update the window crop based on the clip rect.
+        final Rect startClip = new Rect(startBounds);
+        final Rect endClip = new Rect(endBounds);
+        startClip.offsetTo(0, 0);
+        endClip.offsetTo(0, 0);
+        final Animation clipAnim = new ClipRectAnimation(startClip, endClip);
+        clipAnim.setDuration(CHANGE_ANIMATION_DURATION);
+        endSet.addAnimation(clipAnim);
+        endSet.initialize(startBounds.width(), startBounds.height(), parentBounds.width(),
+                parentBounds.height());
+        endSet.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+
+        return new Animation[]{startSet, endSet};
+    }
+
+    @NonNull
+    Animation loadOpenAnimation(@NonNull TransitionInfo.Change change,
+            @NonNull Rect wholeAnimationBounds) {
+        final boolean isEnter = Transitions.isOpeningType(change.getMode());
+        final Animation animation;
+        // TODO(b/207070762):
+        // 1. Implement clearTop version: R.anim.task_fragment_clear_top_close_enter/exit
+        // 2. Implement edgeExtension version
+        animation = mTransitionAnimation.loadDefaultAnimationRes(isEnter
+                ? R.anim.task_fragment_open_enter
+                : R.anim.task_fragment_open_exit);
+        final Rect bounds = change.getEndAbsBounds();
+        animation.initialize(bounds.width(), bounds.height(),
+                wholeAnimationBounds.width(), wholeAnimationBounds.height());
+        animation.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+        return animation;
+    }
+
+    @NonNull
+    Animation loadCloseAnimation(@NonNull TransitionInfo.Change change,
+            @NonNull Rect wholeAnimationBounds) {
+        final boolean isEnter = Transitions.isOpeningType(change.getMode());
+        final Animation animation;
+        // TODO(b/207070762):
+        // 1. Implement clearTop version: R.anim.task_fragment_clear_top_close_enter/exit
+        // 2. Implement edgeExtension version
+        animation = mTransitionAnimation.loadDefaultAnimationRes(isEnter
+                ? R.anim.task_fragment_close_enter
+                : R.anim.task_fragment_close_exit);
+        final Rect bounds = change.getEndAbsBounds();
+        animation.initialize(bounds.width(), bounds.height(),
+                wholeAnimationBounds.width(), wholeAnimationBounds.height());
+        animation.scaleCurrentDuration(mTransitionAnimationScaleSetting);
+        return animation;
+    }
+}

libs/WindowManager/Shell/src/com/android/wm/shell/activityembedding/ActivityEmbeddingController.java

@@ -18,8 +18,11 @@ package com.android.wm.shell.activityembedding;
 
 import static android.window.TransitionInfo.FLAG_IS_EMBEDDED;
 
+import static java.util.Objects.requireNonNull;
+
 import android.content.Context;
 import android.os.IBinder;
+import android.util.ArrayMap;
 import android.view.SurfaceControl;
 import android.window.TransitionInfo;
 import android.window.TransitionRequestInfo;
@@ -28,6 +31,7 @@ import android.window.WindowContainerTransaction;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import com.android.internal.annotations.VisibleForTesting;
 import com.android.wm.shell.sysui.ShellInit;
 import com.android.wm.shell.transition.Transitions;
 
@@ -37,15 +41,37 @@ import com.android.wm.shell.transition.Transitions;
 public class ActivityEmbeddingController implements Transitions.TransitionHandler {
 
     private final Context mContext;
-    private final Transitions mTransitions;
+    @VisibleForTesting
+    final Transitions mTransitions;
+    @VisibleForTesting
+    final ActivityEmbeddingAnimationRunner mAnimationRunner;
 
-    public ActivityEmbeddingController(Context context, ShellInit shellInit,
-            Transitions transitions) {
-        mContext = context;
-        mTransitions = transitions;
-        if (Transitions.ENABLE_SHELL_TRANSITIONS) {
-            shellInit.addInitCallback(this::onInit, this);
-        }
+    /**
+     * Keeps track of the currently-running transition callback associated with each transition
+     * token.
+     */
+    private final ArrayMap<IBinder, Transitions.TransitionFinishCallback> mTransitionCallbacks =
+            new ArrayMap<>();
+
+    private ActivityEmbeddingController(@NonNull Context context, @NonNull ShellInit shellInit,
+            @NonNull Transitions transitions) {
+        mContext = requireNonNull(context);
+        mTransitions = requireNonNull(transitions);
+        mAnimationRunner = new ActivityEmbeddingAnimationRunner(context, this);
+
+        shellInit.addInitCallback(this::onInit, this);
+    }
+
+    /**
+     * Creates {@link ActivityEmbeddingController}, returns {@code null} if the feature is not
+     * supported.
+     */
+    @Nullable
+    public static ActivityEmbeddingController create(@NonNull Context context,
+            @NonNull ShellInit shellInit, @NonNull Transitions transitions) {
+        return Transitions.ENABLE_SHELL_TRANSITIONS
+                ? new ActivityEmbeddingController(context, shellInit, transitions)
+                : null;
     }
 
     /** Registers to handle transitions. */
@@ -66,9 +92,9 @@ public class ActivityEmbeddingController implements Transitions.TransitionHandle
             }
         }
 
-        // TODO(b/207070762) Implement AE animation.
-        startTransaction.apply();
-        finishCallback.onTransitionFinished(null /* wct */, null /* wctCB */);
+        // Start ActivityEmbedding animation.
+        mTransitionCallbacks.put(transition, finishCallback);
+        mAnimationRunner.startAnimation(transition, info, startTransaction, finishTransaction);
         return true;
     }
 
@@ -79,6 +105,21 @@ public class ActivityEmbeddingController implements Transitions.TransitionHandle
         return null;
     }
 
+    @Override
+    public void setAnimScaleSetting(float scale) {
+        mAnimationRunner.setAnimScaleSetting(scale);
+    }
+
+    /** Called when the animation is finished. */
+    void onAnimationFinished(@NonNull IBinder transition) {
+        final Transitions.TransitionFinishCallback callback =
+                mTransitionCallbacks.remove(transition);
+        if (callback == null) {
+            throw new IllegalStateException("No finish callback found");
+        }
+        callback.onTransitionFinished(null /* wct */, null /* wctCB */);
+    }
+
     private static boolean isEmbedded(@NonNull TransitionInfo.Change change) {
         return (change.getFlags() & FLAG_IS_EMBEDDED) != 0;
     }

libs/WindowManager/Shell/src/com/android/wm/shell/dagger/WMShellBaseModule.java

@@ -627,11 +627,12 @@ public abstract class WMShellBaseModule {
 
     @WMSingleton
     @Provides
-    static ActivityEmbeddingController provideActivityEmbeddingController(
+    static Optional<ActivityEmbeddingController> provideActivityEmbeddingController(
             Context context,
             ShellInit shellInit,
             Transitions transitions) {
-        return new ActivityEmbeddingController(context, shellInit, transitions);
+        return Optional.ofNullable(
+                ActivityEmbeddingController.create(context, shellInit, transitions));
     }
 
     //
@@ -686,7 +687,7 @@ public abstract class WMShellBaseModule {
             Optional<RecentTasksController> recentTasksOptional,
             Optional<OneHandedController> oneHandedControllerOptional,
             Optional<HideDisplayCutoutController> hideDisplayCutoutControllerOptional,
-            ActivityEmbeddingController activityEmbeddingOptional,
+            Optional<ActivityEmbeddingController> activityEmbeddingOptional,
             Transitions transitions,
             StartingWindowController startingWindow,
             @ShellCreateTriggerOverride Optional<Object> overriddenCreateTrigger) {

libs/WindowManager/Shell/src/com/android/wm/shell/transition/Transitions.java

@@ -219,6 +219,8 @@ public class Transitions implements RemoteCallable<Transitions> {
                     + "use ShellInit callbacks to ensure proper ordering");
         }
         mHandlers.add(handler);
+        // Set initial scale settings.
+        handler.setAnimScaleSetting(mTransitionAnimationScaleSetting);
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TRANSITIONS, "addHandler: %s",
                 handler.getClass().getSimpleName());
     }

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/activityembedding/ActivityEmbeddingAnimationRunnerTests.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.activityembedding;
+
+import static android.view.WindowManager.TRANSIT_OPEN;
+import static android.window.TransitionInfo.FLAG_IS_EMBEDDED;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+
+import android.window.TransitionInfo;
+
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+import androidx.test.filters.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+
+/**
+ * Tests for {@link ActivityEmbeddingAnimationRunner}.
+ *
+ * Build/Install/Run:
+ *  atest WMShellUnitTests:ActivityEmbeddingAnimationRunnerTests
+ */
+@SmallTest
+@RunWith(AndroidJUnit4.class)
+public class ActivityEmbeddingAnimationRunnerTests extends ActivityEmbeddingAnimationTestBase {
+
+    @Before
+    public void setup() {
+        super.setUp();
+        doNothing().when(mController).onAnimationFinished(any());
+    }
+
+    @Test
+    public void testStartAnimation() {
+        final TransitionInfo info = new TransitionInfo(TRANSIT_OPEN, 0);
+        final TransitionInfo.Change embeddingChange = createChange();
+        embeddingChange.setFlags(FLAG_IS_EMBEDDED);
+        info.addChange(embeddingChange);
+        doReturn(mAnimator).when(mAnimRunner).createAnimator(any(), any(), any(), any());
+
+        mAnimRunner.startAnimation(mTransition, info, mStartTransaction, mFinishTransaction);
+
+        final ArgumentCaptor<Runnable> finishCallback = ArgumentCaptor.forClass(Runnable.class);
+        verify(mAnimRunner).createAnimator(eq(info), eq(mStartTransaction), eq(mFinishTransaction),
+                finishCallback.capture());
+        verify(mStartTransaction).apply();
+        verify(mAnimator).start();
+        verifyNoMoreInteractions(mFinishTransaction);
+        verify(mController, never()).onAnimationFinished(any());
+
+        // Call onAnimationFinished() when the animation is finished.
+        finishCallback.getValue().run();
+
+        verify(mController).onAnimationFinished(mTransition);
+    }
+}

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/activityembedding/ActivityEmbeddingAnimationTestBase.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.activityembedding;
+
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.spyOn;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assume.assumeTrue;
+import static org.mockito.Mockito.mock;
+
+import android.animation.Animator;
+import android.annotation.CallSuper;
+import android.os.IBinder;
+import android.view.SurfaceControl;
+import android.window.TransitionInfo;
+import android.window.WindowContainerToken;
+
+import com.android.wm.shell.ShellTestCase;
+import com.android.wm.shell.sysui.ShellInit;
+import com.android.wm.shell.transition.Transitions;
+
+import org.junit.Before;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/** TestBase for ActivityEmbedding animation. */
+abstract class ActivityEmbeddingAnimationTestBase extends ShellTestCase {
+
+    @Mock
+    ShellInit mShellInit;
+    @Mock
+    Transitions mTransitions;
+    @Mock
+    IBinder mTransition;
+    @Mock
+    SurfaceControl.Transaction mStartTransaction;
+    @Mock
+    SurfaceControl.Transaction mFinishTransaction;
+    @Mock
+    Transitions.TransitionFinishCallback mFinishCallback;
+    @Mock
+    Animator mAnimator;
+
+    ActivityEmbeddingController mController;
+    ActivityEmbeddingAnimationRunner mAnimRunner;
+    ActivityEmbeddingAnimationSpec mAnimSpec;
+
+    @CallSuper
+    @Before
+    public void setUp() {
+        assumeTrue(Transitions.ENABLE_SHELL_TRANSITIONS);
+        MockitoAnnotations.initMocks(this);
+        mController = ActivityEmbeddingController.create(mContext, mShellInit, mTransitions);
+        assertNotNull(mController);
+        mAnimRunner = mController.mAnimationRunner;
+        assertNotNull(mAnimRunner);
+        mAnimSpec = mAnimRunner.mAnimationSpec;
+        assertNotNull(mAnimSpec);
+        spyOn(mController);
+        spyOn(mAnimRunner);
+        spyOn(mAnimSpec);
+    }
+
+    /** Creates a mock {@link TransitionInfo.Change}. */
+    static TransitionInfo.Change createChange() {
+        return new TransitionInfo.Change(mock(WindowContainerToken.class),
+                mock(SurfaceControl.class));
+    }
+}

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/activityembedding/ActivityEmbeddingControllerTests.java

@@ -16,52 +16,117 @@
 
 package com.android.wm.shell.activityembedding;
 
-import static com.android.dx.mockito.inline.extended.ExtendedMockito.spy;
+import static android.view.WindowManager.TRANSIT_OPEN;
+import static android.window.TransitionInfo.FLAG_IS_EMBEDDED;
 
-import static org.junit.Assume.assumeTrue;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.never;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
 
-import android.content.Context;
+import android.window.TransitionInfo;
 
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import androidx.test.filters.SmallTest;
 
-import com.android.wm.shell.ShellTestCase;
-import com.android.wm.shell.sysui.ShellInit;
-import com.android.wm.shell.transition.Transitions;
-
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
 
 /**
- * Tests for the activity embedding controller.
+ * Tests for {@link ActivityEmbeddingController}.
  *
  * Build/Install/Run:
  *  atest WMShellUnitTests:ActivityEmbeddingControllerTests
  */
 @SmallTest
 @RunWith(AndroidJUnit4.class)
-public class ActivityEmbeddingControllerTests extends ShellTestCase {
-
-    private @Mock Context mContext;
-    private @Mock ShellInit mShellInit;
-    private @Mock Transitions mTransitions;
-    private ActivityEmbeddingController mController;
+public class ActivityEmbeddingControllerTests extends ActivityEmbeddingAnimationTestBase {
 
     @Before
-    public void setUp() {
-        MockitoAnnotations.initMocks(this);
-        mController = spy(new ActivityEmbeddingController(mContext, mShellInit, mTransitions));
+    public void setup() {
+        super.setUp();
+        doReturn(mAnimator).when(mAnimRunner).createAnimator(any(), any(), any(), any());
     }
 
     @Test
-    public void instantiate_addInitCallback() {
-        assumeTrue(Transitions.ENABLE_SHELL_TRANSITIONS);
-        verify(mShellInit, times(1)).addInitCallback(any(), any());
+    public void testInstantiate() {
+        verify(mShellInit).addInitCallback(any(), any());
+    }
+
+    @Test
+    public void testOnInit() {
+        mController.onInit();
+
+        verify(mTransitions).addHandler(mController);
+    }
+
+    @Test
+    public void testSetAnimScaleSetting() {
+        mController.setAnimScaleSetting(1.0f);
+
+        verify(mAnimRunner).setAnimScaleSetting(1.0f);
+        verify(mAnimSpec).setAnimScaleSetting(1.0f);
+    }
+
+    @Test
+    public void testStartAnimation_containsNonActivityEmbeddingChange() {
+        final TransitionInfo info = new TransitionInfo(TRANSIT_OPEN, 0);
+        final TransitionInfo.Change embeddingChange = createChange();
+        embeddingChange.setFlags(FLAG_IS_EMBEDDED);
+        final TransitionInfo.Change nonEmbeddingChange = createChange();
+        info.addChange(embeddingChange);
+        info.addChange(nonEmbeddingChange);
+
+        // No-op
+        assertFalse(mController.startAnimation(mTransition, info, mStartTransaction,
+                mFinishTransaction, mFinishCallback));
+        verify(mAnimRunner, never()).startAnimation(any(), any(), any(), any());
+        verifyNoMoreInteractions(mStartTransaction);
+        verifyNoMoreInteractions(mFinishTransaction);
+        verifyNoMoreInteractions(mFinishCallback);
+    }
+
+    @Test
+    public void testStartAnimation_onlyActivityEmbeddingChange() {
+        final TransitionInfo info = new TransitionInfo(TRANSIT_OPEN, 0);
+        final TransitionInfo.Change embeddingChange = createChange();
+        embeddingChange.setFlags(FLAG_IS_EMBEDDED);
+        info.addChange(embeddingChange);
+
+        // No-op
+        assertTrue(mController.startAnimation(mTransition, info, mStartTransaction,
+                mFinishTransaction, mFinishCallback));
+        verify(mAnimRunner).startAnimation(mTransition, info, mStartTransaction,
+                mFinishTransaction);
+        verify(mStartTransaction).apply();
+        verifyNoMoreInteractions(mFinishTransaction);
+    }
+
+    @Test
+    public void testOnAnimationFinished() {
+        // Should not call finish when there is no transition.
+        assertThrows(IllegalStateException.class,
+                () -> mController.onAnimationFinished(mTransition));
+
+        final TransitionInfo info = new TransitionInfo(TRANSIT_OPEN, 0);
+        final TransitionInfo.Change embeddingChange = createChange();
+        embeddingChange.setFlags(FLAG_IS_EMBEDDED);
+        info.addChange(embeddingChange);
+        mController.startAnimation(mTransition, info, mStartTransaction,
+                mFinishTransaction, mFinishCallback);
+
+        verify(mFinishCallback, never()).onTransitionFinished(any(), any());
+        mController.onAnimationFinished(mTransition);
+        verify(mFinishCallback).onTransitionFinished(any(), any());
+
+        // Should not call finish when the finish has already been called.
+        assertThrows(IllegalStateException.class,
+                () -> mController.onAnimationFinished(mTransition));
     }
 }