android-34/com/android/systemui/dreams/touch/BouncerSwipeTouchHandler.java - platform/prebuilts/fullsdk/sources - Git at Google

 /*
  * 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.systemui.dreams.touch;

 import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_CLOSING;
 import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_OPENING;
 import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_START_REGION;

 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.ValueAnimator;
 import android.graphics.Rect;
 import android.graphics.Region;
 import android.util.Log;
 import android.view.GestureDetector;
 import android.view.InputEvent;
 import android.view.MotionEvent;
 import android.view.VelocityTracker;

 import androidx.annotation.VisibleForTesting;

 import com.android.internal.logging.UiEvent;
 import com.android.internal.logging.UiEventLogger;
 import com.android.systemui.dreams.touch.scrim.ScrimController;
 import com.android.systemui.dreams.touch.scrim.ScrimManager;
 import com.android.systemui.keyguard.shared.constants.KeyguardBouncerConstants;
 import com.android.systemui.shade.ShadeExpansionChangeEvent;
 import com.android.systemui.statusbar.NotificationShadeWindowController;
 import com.android.systemui.statusbar.phone.CentralSurfaces;
 import com.android.wm.shell.animation.FlingAnimationUtils;

 import java.util.Optional;

 import javax.inject.Inject;
 import javax.inject.Named;

 /**
  * Monitor for tracking touches on the DreamOverlay to bring up the bouncer.
  */
 public class BouncerSwipeTouchHandler implements DreamTouchHandler {
     /**
      * An interface for creating ValueAnimators.
      */
     public interface ValueAnimatorCreator {
         /**
          * Creates {@link ValueAnimator}.
          */
         ValueAnimator create(float start, float finish);
     }

     /**
      * An interface for obtaining VelocityTrackers.
      */
     public interface VelocityTrackerFactory {
         /**
          * Obtains {@link VelocityTracker}.
          */
         VelocityTracker obtain();
     }

     public static final float FLING_PERCENTAGE_THRESHOLD = 0.5f;

     private static final String TAG = "BouncerSwipeTouchHandler";
     private final NotificationShadeWindowController mNotificationShadeWindowController;
     private final float mBouncerZoneScreenPercentage;

     private final ScrimManager mScrimManager;
     private ScrimController mCurrentScrimController;
     private float mCurrentExpansion;
     private final Optional<CentralSurfaces> mCentralSurfaces;

     private VelocityTracker mVelocityTracker;

     private final FlingAnimationUtils mFlingAnimationUtils;
     private final FlingAnimationUtils mFlingAnimationUtilsClosing;

     private Boolean mCapture;
     private Boolean mExpanded;

     private boolean mBouncerInitiallyShowing;

     private TouchSession mTouchSession;

     private ValueAnimatorCreator mValueAnimatorCreator;

     private VelocityTrackerFactory mVelocityTrackerFactory;

     private final UiEventLogger mUiEventLogger;

     private final ScrimManager.Callback mScrimManagerCallback = new ScrimManager.Callback() {
         @Override
         public void onScrimControllerChanged(ScrimController controller) {
             if (mCurrentScrimController != null) {
                 mCurrentScrimController.reset();
             }

             mCurrentScrimController = controller;
         }
     };

     private final GestureDetector.OnGestureListener mOnGestureListener =
             new GestureDetector.SimpleOnGestureListener() {
                 @Override
                 public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
                         float distanceY) {
                     if (mCapture == null) {
                         // If the user scrolling favors a vertical direction, begin capturing
                         // scrolls.
                         mCapture = Math.abs(distanceY) > Math.abs(distanceX);
                         mBouncerInitiallyShowing = mCentralSurfaces
                                 .map(CentralSurfaces::isBouncerShowing)
                                 .orElse(false);

                         if (mCapture) {
                             // reset expanding
                             mExpanded = false;
                             // Since the user is dragging the bouncer up, set scrimmed to false.
                             mCurrentScrimController.show();
                         }
                     }

                     if (!mCapture) {
                         return false;
                     }

                     // Don't set expansion for downward scroll when the bouncer is hidden.
                     if (!mBouncerInitiallyShowing && (e1.getY() < e2.getY())) {
                         return true;
                     }

                     // Don't set expansion for upward scroll when the bouncer is shown.
                     if (mBouncerInitiallyShowing && (e1.getY() > e2.getY())) {
                         return true;
                     }

                     if (!mCentralSurfaces.isPresent()) {
                         return true;
                     }

                     // For consistency, we adopt the expansion definition found in the
                     // PanelViewController. In this case, expansion refers to the view above the
                     // bouncer. As that view's expansion shrinks, the bouncer appears. The bouncer
                     // is fully hidden at full expansion (1) and fully visible when fully collapsed
                     // (0).
                     final float dragDownAmount = e2.getY() - e1.getY();
                     final float screenTravelPercentage = Math.abs(e1.getY() - e2.getY())
                             / mTouchSession.getBounds().height();
                     setPanelExpansion(mBouncerInitiallyShowing
                             ? screenTravelPercentage : 1 - screenTravelPercentage, dragDownAmount);
                     return true;
                 }
             };

     private void setPanelExpansion(float expansion, float dragDownAmount) {
         mCurrentExpansion = expansion;
         ShadeExpansionChangeEvent event =
                 new ShadeExpansionChangeEvent(
                         /* fraction= */ mCurrentExpansion,
                         /* expanded= */ mExpanded,
                         /* tracking= */ true,
                         /* dragDownPxAmount= */ dragDownAmount);
         mCurrentScrimController.expand(event);
     }


     @VisibleForTesting
     public enum DreamEvent implements UiEventLogger.UiEventEnum {
         @UiEvent(doc = "The screensaver has been swiped up.")
         DREAM_SWIPED(988),

         @UiEvent(doc = "The bouncer has become fully visible over dream.")
         DREAM_BOUNCER_FULLY_VISIBLE(1056);

         private final int mId;

         DreamEvent(int id) {
             mId = id;
         }

         @Override
         public int getId() {
             return mId;
         }
     }

     @Inject
     public BouncerSwipeTouchHandler(
             ScrimManager scrimManager,
             Optional<CentralSurfaces> centralSurfaces,
             NotificationShadeWindowController notificationShadeWindowController,
             ValueAnimatorCreator valueAnimatorCreator,
             VelocityTrackerFactory velocityTrackerFactory,
             @Named(SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_OPENING)
                     FlingAnimationUtils flingAnimationUtils,
             @Named(SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_CLOSING)
                     FlingAnimationUtils flingAnimationUtilsClosing,
             @Named(SWIPE_TO_BOUNCER_START_REGION) float swipeRegionPercentage,
             UiEventLogger uiEventLogger) {
         mCentralSurfaces = centralSurfaces;
         mScrimManager = scrimManager;
         mNotificationShadeWindowController = notificationShadeWindowController;
         mBouncerZoneScreenPercentage = swipeRegionPercentage;
         mFlingAnimationUtils = flingAnimationUtils;
         mFlingAnimationUtilsClosing = flingAnimationUtilsClosing;
         mValueAnimatorCreator = valueAnimatorCreator;
         mVelocityTrackerFactory = velocityTrackerFactory;
         mUiEventLogger = uiEventLogger;
     }

     @Override
     public void getTouchInitiationRegion(Rect bounds, Region region) {
         final int width = bounds.width();
         final int height = bounds.height();

         if (mCentralSurfaces.map(CentralSurfaces::isBouncerShowing).orElse(false)) {
             region.op(new Rect(0, 0, width,
                             Math.round(
                                     height * mBouncerZoneScreenPercentage)),
                     Region.Op.UNION);
         } else {
             region.op(new Rect(0,
                             Math.round(height * (1 - mBouncerZoneScreenPercentage)),
                             width,
                             height),
                     Region.Op.UNION);
         }
     }

     @Override
     public void onSessionStart(TouchSession session) {
         mVelocityTracker = mVelocityTrackerFactory.obtain();
         mTouchSession = session;
         mVelocityTracker.clear();
         mNotificationShadeWindowController.setForcePluginOpen(true, this);
         mScrimManager.addCallback(mScrimManagerCallback);
         mCurrentScrimController = mScrimManager.getCurrentController();

         session.registerCallback(() -> {
             if (mVelocityTracker != null) {
                 mVelocityTracker.recycle();
                 mVelocityTracker = null;
             }
             mScrimManager.removeCallback(mScrimManagerCallback);
             mCapture = null;
             mNotificationShadeWindowController.setForcePluginOpen(false, this);
         });

         session.registerGestureListener(mOnGestureListener);
         session.registerInputListener(ev -> onMotionEvent(ev));

     }

     private void onMotionEvent(InputEvent event) {
         if (!(event instanceof MotionEvent)) {
             Log.e(TAG, "non MotionEvent received:" + event);
             return;
         }

         final MotionEvent motionEvent = (MotionEvent) event;

         switch (motionEvent.getAction()) {
             case MotionEvent.ACTION_CANCEL:
             case MotionEvent.ACTION_UP:
                 mTouchSession.pop();
                 // If we are not capturing any input, there is no need to consider animating to
                 // finish transition.
                 if (mCapture == null || !mCapture) {
                     break;
                 }

                 // We must capture the resulting velocities as resetMonitor() will clear these
                 // values.
                 mVelocityTracker.computeCurrentVelocity(1000);
                 final float verticalVelocity = mVelocityTracker.getYVelocity();
                 final float horizontalVelocity = mVelocityTracker.getXVelocity();

                 final float velocityVector =
                         (float) Math.hypot(horizontalVelocity, verticalVelocity);

                 mExpanded = !flingRevealsOverlay(verticalVelocity, velocityVector);
                 final float expansion = mExpanded
                         ? KeyguardBouncerConstants.EXPANSION_VISIBLE
                         : KeyguardBouncerConstants.EXPANSION_HIDDEN;

                 // Log the swiping up to show Bouncer event.
                 if (!mBouncerInitiallyShowing
                         && expansion == KeyguardBouncerConstants.EXPANSION_VISIBLE) {
                     mUiEventLogger.log(DreamEvent.DREAM_SWIPED);
                 }

                 flingToExpansion(verticalVelocity, expansion);
                 break;
             default:
                 mVelocityTracker.addMovement(motionEvent);
                 break;
         }
     }

     private ValueAnimator createExpansionAnimator(float targetExpansion, float expansionHeight) {
         final ValueAnimator animator =
                 mValueAnimatorCreator.create(mCurrentExpansion, targetExpansion);
         animator.addUpdateListener(
                 animation -> {
                     float expansionFraction = (float) animation.getAnimatedValue();
                     float dragDownAmount = expansionFraction * expansionHeight;
                     setPanelExpansion(expansionFraction, dragDownAmount);
                 });
         if (!mBouncerInitiallyShowing
                 && targetExpansion == KeyguardBouncerConstants.EXPANSION_VISIBLE) {
             animator.addListener(
                     new AnimatorListenerAdapter() {
                         @Override
                         public void onAnimationEnd(Animator animation) {
                             mUiEventLogger.log(DreamEvent.DREAM_BOUNCER_FULLY_VISIBLE);
                         }
                     });
         }
         return animator;
     }

     protected boolean flingRevealsOverlay(float velocity, float velocityVector) {
         // Fully expand the space above the bouncer, if the user has expanded the bouncer less
         // than halfway or final velocity was positive, indicating a downward direction.
         if (Math.abs(velocityVector) < mFlingAnimationUtils.getMinVelocityPxPerSecond()) {
             return mCurrentExpansion > FLING_PERCENTAGE_THRESHOLD;
         } else {
             return velocity > 0;
         }
     }

     protected void flingToExpansion(float velocity, float expansion) {
         if (!mCentralSurfaces.isPresent()) {
             return;
         }

         // The animation utils deal in pixel units, rather than expansion height.
         final float viewHeight = mTouchSession.getBounds().height();
         final float currentHeight = viewHeight * mCurrentExpansion;
         final float targetHeight = viewHeight * expansion;
         final float expansionHeight = targetHeight - currentHeight;
         final ValueAnimator animator = createExpansionAnimator(expansion, expansionHeight);
         if (expansion == KeyguardBouncerConstants.EXPANSION_HIDDEN) {
             // Hides the bouncer, i.e., fully expands the space above the bouncer.
             mFlingAnimationUtilsClosing.apply(animator, currentHeight, targetHeight, velocity,
                     viewHeight);
         } else {
             // Shows the bouncer, i.e., fully collapses the space above the bouncer.
             mFlingAnimationUtils.apply(
                     animator, currentHeight, targetHeight, velocity, viewHeight);
         }

         animator.start();
     }
 }
	/*
	* 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.systemui.dreams.touch;

	import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_CLOSING;
	import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_OPENING;
	import static com.android.systemui.dreams.touch.dagger.BouncerSwipeModule.SWIPE_TO_BOUNCER_START_REGION;

	import android.animation.Animator;
	import android.animation.AnimatorListenerAdapter;
	import android.animation.ValueAnimator;
	import android.graphics.Rect;
	import android.graphics.Region;
	import android.util.Log;
	import android.view.GestureDetector;
	import android.view.InputEvent;
	import android.view.MotionEvent;
	import android.view.VelocityTracker;

	import androidx.annotation.VisibleForTesting;

	import com.android.internal.logging.UiEvent;
	import com.android.internal.logging.UiEventLogger;
	import com.android.systemui.dreams.touch.scrim.ScrimController;
	import com.android.systemui.dreams.touch.scrim.ScrimManager;
	import com.android.systemui.keyguard.shared.constants.KeyguardBouncerConstants;
	import com.android.systemui.shade.ShadeExpansionChangeEvent;
	import com.android.systemui.statusbar.NotificationShadeWindowController;
	import com.android.systemui.statusbar.phone.CentralSurfaces;
	import com.android.wm.shell.animation.FlingAnimationUtils;

	import java.util.Optional;

	import javax.inject.Inject;
	import javax.inject.Named;

	/**
	* Monitor for tracking touches on the DreamOverlay to bring up the bouncer.
	*/
	public class BouncerSwipeTouchHandler implements DreamTouchHandler {
	/**
	* An interface for creating ValueAnimators.
	*/
	public interface ValueAnimatorCreator {
	/**
	* Creates {@link ValueAnimator}.
	*/
	ValueAnimator create(float start, float finish);
	}

	/**
	* An interface for obtaining VelocityTrackers.
	*/
	public interface VelocityTrackerFactory {
	/**
	* Obtains {@link VelocityTracker}.
	*/
	VelocityTracker obtain();
	}

	public static final float FLING_PERCENTAGE_THRESHOLD = 0.5f;

	private static final String TAG = "BouncerSwipeTouchHandler";
	private final NotificationShadeWindowController mNotificationShadeWindowController;
	private final float mBouncerZoneScreenPercentage;

	private final ScrimManager mScrimManager;
	private ScrimController mCurrentScrimController;
	private float mCurrentExpansion;
	private final Optional<CentralSurfaces> mCentralSurfaces;

	private VelocityTracker mVelocityTracker;

	private final FlingAnimationUtils mFlingAnimationUtils;
	private final FlingAnimationUtils mFlingAnimationUtilsClosing;

	private Boolean mCapture;
	private Boolean mExpanded;

	private boolean mBouncerInitiallyShowing;

	private TouchSession mTouchSession;

	private ValueAnimatorCreator mValueAnimatorCreator;

	private VelocityTrackerFactory mVelocityTrackerFactory;

	private final UiEventLogger mUiEventLogger;

	private final ScrimManager.Callback mScrimManagerCallback = new ScrimManager.Callback() {
	@Override
	public void onScrimControllerChanged(ScrimController controller) {
	if (mCurrentScrimController != null) {
	mCurrentScrimController.reset();
	}

	mCurrentScrimController = controller;
	}
	};

	private final GestureDetector.OnGestureListener mOnGestureListener =
	new GestureDetector.SimpleOnGestureListener() {
	@Override
	public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
	float distanceY) {
	if (mCapture == null) {
	// If the user scrolling favors a vertical direction, begin capturing
	// scrolls.
	mCapture = Math.abs(distanceY) > Math.abs(distanceX);
	mBouncerInitiallyShowing = mCentralSurfaces
	.map(CentralSurfaces::isBouncerShowing)
	.orElse(false);

	if (mCapture) {
	// reset expanding
	mExpanded = false;
	// Since the user is dragging the bouncer up, set scrimmed to false.
	mCurrentScrimController.show();
	}
	}

	if (!mCapture) {
	return false;
	}

	// Don't set expansion for downward scroll when the bouncer is hidden.
	if (!mBouncerInitiallyShowing && (e1.getY() < e2.getY())) {
	return true;
	}

	// Don't set expansion for upward scroll when the bouncer is shown.
	if (mBouncerInitiallyShowing && (e1.getY() > e2.getY())) {
	return true;
	}

	if (!mCentralSurfaces.isPresent()) {
	return true;
	}

	// For consistency, we adopt the expansion definition found in the
	// PanelViewController. In this case, expansion refers to the view above the
	// bouncer. As that view's expansion shrinks, the bouncer appears. The bouncer
	// is fully hidden at full expansion (1) and fully visible when fully collapsed
	// (0).
	final float dragDownAmount = e2.getY() - e1.getY();
	final float screenTravelPercentage = Math.abs(e1.getY() - e2.getY())
	/ mTouchSession.getBounds().height();
	setPanelExpansion(mBouncerInitiallyShowing
	? screenTravelPercentage : 1 - screenTravelPercentage, dragDownAmount);
	return true;
	}
	};

	private void setPanelExpansion(float expansion, float dragDownAmount) {
	mCurrentExpansion = expansion;
	ShadeExpansionChangeEvent event =
	new ShadeExpansionChangeEvent(
	/* fraction= */ mCurrentExpansion,
	/* expanded= */ mExpanded,
	/* tracking= */ true,
	/* dragDownPxAmount= */ dragDownAmount);
	mCurrentScrimController.expand(event);
	}


	@VisibleForTesting
	public enum DreamEvent implements UiEventLogger.UiEventEnum {
	@UiEvent(doc = "The screensaver has been swiped up.")
	DREAM_SWIPED(988),

	@UiEvent(doc = "The bouncer has become fully visible over dream.")
	DREAM_BOUNCER_FULLY_VISIBLE(1056);

	private final int mId;

	DreamEvent(int id) {
	mId = id;
	}

	@Override
	public int getId() {
	return mId;
	}
	}

	@Inject
	public BouncerSwipeTouchHandler(
	ScrimManager scrimManager,
	Optional<CentralSurfaces> centralSurfaces,
	NotificationShadeWindowController notificationShadeWindowController,
	ValueAnimatorCreator valueAnimatorCreator,
	VelocityTrackerFactory velocityTrackerFactory,
	@Named(SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_OPENING)
	FlingAnimationUtils flingAnimationUtils,
	@Named(SWIPE_TO_BOUNCER_FLING_ANIMATION_UTILS_CLOSING)
	FlingAnimationUtils flingAnimationUtilsClosing,
	@Named(SWIPE_TO_BOUNCER_START_REGION) float swipeRegionPercentage,
	UiEventLogger uiEventLogger) {
	mCentralSurfaces = centralSurfaces;
	mScrimManager = scrimManager;
	mNotificationShadeWindowController = notificationShadeWindowController;
	mBouncerZoneScreenPercentage = swipeRegionPercentage;
	mFlingAnimationUtils = flingAnimationUtils;
	mFlingAnimationUtilsClosing = flingAnimationUtilsClosing;
	mValueAnimatorCreator = valueAnimatorCreator;
	mVelocityTrackerFactory = velocityTrackerFactory;
	mUiEventLogger = uiEventLogger;
	}

	@Override
	public void getTouchInitiationRegion(Rect bounds, Region region) {
	final int width = bounds.width();
	final int height = bounds.height();

	if (mCentralSurfaces.map(CentralSurfaces::isBouncerShowing).orElse(false)) {
	region.op(new Rect(0, 0, width,
	Math.round(
	height * mBouncerZoneScreenPercentage)),
	Region.Op.UNION);
	} else {
	region.op(new Rect(0,
	Math.round(height * (1 - mBouncerZoneScreenPercentage)),
	width,
	height),
	Region.Op.UNION);
	}
	}

	@Override
	public void onSessionStart(TouchSession session) {
	mVelocityTracker = mVelocityTrackerFactory.obtain();
	mTouchSession = session;
	mVelocityTracker.clear();
	mNotificationShadeWindowController.setForcePluginOpen(true, this);
	mScrimManager.addCallback(mScrimManagerCallback);
	mCurrentScrimController = mScrimManager.getCurrentController();

	session.registerCallback(() -> {
	if (mVelocityTracker != null) {
	mVelocityTracker.recycle();
	mVelocityTracker = null;
	}
	mScrimManager.removeCallback(mScrimManagerCallback);
	mCapture = null;
	mNotificationShadeWindowController.setForcePluginOpen(false, this);
	});

	session.registerGestureListener(mOnGestureListener);
	session.registerInputListener(ev -> onMotionEvent(ev));

	}

	private void onMotionEvent(InputEvent event) {
	if (!(event instanceof MotionEvent)) {
	Log.e(TAG, "non MotionEvent received:" + event);
	return;
	}

	final MotionEvent motionEvent = (MotionEvent) event;

	switch (motionEvent.getAction()) {
	case MotionEvent.ACTION_CANCEL:
	case MotionEvent.ACTION_UP:
	mTouchSession.pop();
	// If we are not capturing any input, there is no need to consider animating to
	// finish transition.
	if (mCapture == null \|\| !mCapture) {
	break;
	}

	// We must capture the resulting velocities as resetMonitor() will clear these
	// values.
	mVelocityTracker.computeCurrentVelocity(1000);
	final float verticalVelocity = mVelocityTracker.getYVelocity();
	final float horizontalVelocity = mVelocityTracker.getXVelocity();

	final float velocityVector =
	(float) Math.hypot(horizontalVelocity, verticalVelocity);

	mExpanded = !flingRevealsOverlay(verticalVelocity, velocityVector);
	final float expansion = mExpanded
	? KeyguardBouncerConstants.EXPANSION_VISIBLE
	: KeyguardBouncerConstants.EXPANSION_HIDDEN;

	// Log the swiping up to show Bouncer event.
	if (!mBouncerInitiallyShowing
	&& expansion == KeyguardBouncerConstants.EXPANSION_VISIBLE) {
	mUiEventLogger.log(DreamEvent.DREAM_SWIPED);
	}

	flingToExpansion(verticalVelocity, expansion);
	break;
	default:
	mVelocityTracker.addMovement(motionEvent);
	break;
	}
	}

	private ValueAnimator createExpansionAnimator(float targetExpansion, float expansionHeight) {
	final ValueAnimator animator =
	mValueAnimatorCreator.create(mCurrentExpansion, targetExpansion);
	animator.addUpdateListener(
	animation -> {
	float expansionFraction = (float) animation.getAnimatedValue();
	float dragDownAmount = expansionFraction * expansionHeight;
	setPanelExpansion(expansionFraction, dragDownAmount);
	});
	if (!mBouncerInitiallyShowing
	&& targetExpansion == KeyguardBouncerConstants.EXPANSION_VISIBLE) {
	animator.addListener(
	new AnimatorListenerAdapter() {
	@Override
	public void onAnimationEnd(Animator animation) {
	mUiEventLogger.log(DreamEvent.DREAM_BOUNCER_FULLY_VISIBLE);
	}
	});
	}
	return animator;
	}

	protected boolean flingRevealsOverlay(float velocity, float velocityVector) {
	// Fully expand the space above the bouncer, if the user has expanded the bouncer less
	// than halfway or final velocity was positive, indicating a downward direction.
	if (Math.abs(velocityVector) < mFlingAnimationUtils.getMinVelocityPxPerSecond()) {
	return mCurrentExpansion > FLING_PERCENTAGE_THRESHOLD;
	} else {
	return velocity > 0;
	}
	}

	protected void flingToExpansion(float velocity, float expansion) {
	if (!mCentralSurfaces.isPresent()) {
	return;
	}

	// The animation utils deal in pixel units, rather than expansion height.
	final float viewHeight = mTouchSession.getBounds().height();
	final float currentHeight = viewHeight * mCurrentExpansion;
	final float targetHeight = viewHeight * expansion;
	final float expansionHeight = targetHeight - currentHeight;
	final ValueAnimator animator = createExpansionAnimator(expansion, expansionHeight);
	if (expansion == KeyguardBouncerConstants.EXPANSION_HIDDEN) {
	// Hides the bouncer, i.e., fully expands the space above the bouncer.
	mFlingAnimationUtilsClosing.apply(animator, currentHeight, targetHeight, velocity,
	viewHeight);
	} else {
	// Shows the bouncer, i.e., fully collapses the space above the bouncer.
	mFlingAnimationUtils.apply(
	animator, currentHeight, targetHeight, velocity, viewHeight);
	}

	animator.start();
	}
	}