android/android-9.0.0_r35 : android/service/wallpaper/WallpaperService.java

WallpaperService
https://source.android.com/
/*
 * Copyright (C) 2009 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 android.service.wallpaper;

import android.annotation.Nullable;
import android.annotation.SdkConstant;
import android.annotation.SdkConstant.SdkConstantType;
import android.app.Service;
import android.app.WallpaperColors;
import android.app.WallpaperManager;
import android.content.Context;
import android.content.Intent;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.hardware.display.DisplayManager;
import android.hardware.display.DisplayManager.DisplayListener;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.RemoteException;
import android.os.SystemClock;
import android.util.Log;
import android.util.MergedConfiguration;
import android.view.Display;
import android.view.DisplayCutout;
import android.view.Gravity;
import android.view.IWindowSession;
import android.view.InputChannel;
import android.view.InputDevice;
import android.view.InputEvent;
import android.view.InputEventReceiver;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowInsets;
import android.view.WindowManager;
import android.view.WindowManagerGlobal;

import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.os.HandlerCaller;
import com.android.internal.view.BaseIWindow;
import com.android.internal.view.BaseSurfaceHolder;

import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.function.Supplier;

A wallpaper service is responsible for showing a live wallpaper behind applications that would like to sit on top of it. This service object itself does very little -- its only purpose is to generate instances of Engine as needed. Implementing a wallpaper thus involves subclassing from this, subclassing an Engine implementation, and implementing onCreateEngine() to return a new instance of your engine. /**
 * A wallpaper service is responsible for showing a live wallpaper behind
 * applications that would like to sit on top of it.  This service object
 * itself does very little -- its only purpose is to generate instances of
 * {@link Engine} as needed.  Implementing a wallpaper thus
 * involves subclassing from this, subclassing an Engine implementation,
 * and implementing {@link #onCreateEngine()} to return a new instance of
 * your engine.
 */
public abstract class WallpaperService extends Service {
    The Intent that must be declared as handled by the service. To be supported, the service must also require the BIND_WALLPAPER.BIND_WALLPAPER permission so that other applications can not abuse it. /**
     * The {@link Intent} that must be declared as handled by the service.
     * To be supported, the service must also require the
     * {@link android.Manifest.permission#BIND_WALLPAPER} permission so
     * that other applications can not abuse it.
     */
    @SdkConstant(SdkConstantType.SERVICE_ACTION)
    public static final String SERVICE_INTERFACE =
            "android.service.wallpaper.WallpaperService";

    Name under which a WallpaperService component publishes information
about itself.  This meta-data must reference an XML resource containing
a <wallpaper>
tag.
/**
     * Name under which a WallpaperService component publishes information
     * about itself.  This meta-data must reference an XML resource containing
     * a <code>&lt;{@link android.R.styleable#Wallpaper wallpaper}&gt;</code>
     * tag.
     */
    public static final String SERVICE_META_DATA = "android.service.wallpaper";

    static final String TAG = "WallpaperService";
    static final boolean DEBUG = false;
    
    private static final int DO_ATTACH = 10;
    private static final int DO_DETACH = 20;
    private static final int DO_SET_DESIRED_SIZE = 30;
    private static final int DO_SET_DISPLAY_PADDING = 40;
    private static final int DO_IN_AMBIENT_MODE = 50;

    private static final int MSG_UPDATE_SURFACE = 10000;
    private static final int MSG_VISIBILITY_CHANGED = 10010;
    private static final int MSG_WALLPAPER_OFFSETS = 10020;
    private static final int MSG_WALLPAPER_COMMAND = 10025;
    private static final int MSG_WINDOW_RESIZED = 10030;
    private static final int MSG_WINDOW_MOVED = 10035;
    private static final int MSG_TOUCH_EVENT = 10040;
    private static final int MSG_REQUEST_WALLPAPER_COLORS = 10050;

    private static final int NOTIFY_COLORS_RATE_LIMIT_MS = 1000;

    private final ArrayList<Engine> mActiveEngines
            = new ArrayList<Engine>();
    
    static final class WallpaperCommand {
        String action;
        int x;
        int y;
        int z;
        Bundle extras;
        boolean sync;
    }
    
    The actual implementation of a wallpaper. A wallpaper service may have multiple instances running (for example as a real wallpaper and as a preview), each of which is represented by its own Engine instance. You must implement WallpaperService.onCreateEngine() to return your concrete Engine implementation. /**
     * The actual implementation of a wallpaper.  A wallpaper service may
     * have multiple instances running (for example as a real wallpaper
     * and as a preview), each of which is represented by its own Engine
     * instance.  You must implement {@link WallpaperService#onCreateEngine()}
     * to return your concrete Engine implementation.
     */
    public class Engine {
        IWallpaperEngineWrapper mIWallpaperEngine;
        
        // Copies from mIWallpaperEngine.
        HandlerCaller mCaller;
        IWallpaperConnection mConnection;
        IBinder mWindowToken;
        
        boolean mInitializing = true;
        boolean mVisible;
        boolean mReportedVisible;
        boolean mDestroyed;
        
        // Current window state.
        boolean mCreated;
        boolean mSurfaceCreated;
        boolean mIsCreating;
        boolean mDrawingAllowed;
        boolean mOffsetsChanged;
        boolean mFixedSizeAllowed;
        int mWidth;
        int mHeight;
        int mFormat;
        int mType;
        int mCurWidth;
        int mCurHeight;
        int mWindowFlags = WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;
        int mWindowPrivateFlags =
                WindowManager.LayoutParams.PRIVATE_FLAG_WANTS_OFFSET_NOTIFICATIONS;
        int mCurWindowFlags = mWindowFlags;
        int mCurWindowPrivateFlags = mWindowPrivateFlags;
        final Rect mVisibleInsets = new Rect();
        final Rect mWinFrame = new Rect();
        final Rect mOverscanInsets = new Rect();
        final Rect mContentInsets = new Rect();
        final Rect mStableInsets = new Rect();
        final Rect mOutsets = new Rect();
        final Rect mDispatchedOverscanInsets = new Rect();
        final Rect mDispatchedContentInsets = new Rect();
        final Rect mDispatchedStableInsets = new Rect();
        final Rect mDispatchedOutsets = new Rect();
        final Rect mFinalSystemInsets = new Rect();
        final Rect mFinalStableInsets = new Rect();
        final Rect mBackdropFrame = new Rect();
        final DisplayCutout.ParcelableWrapper mDisplayCutout =
                new DisplayCutout.ParcelableWrapper();
        DisplayCutout mDispatchedDisplayCutout = DisplayCutout.NO_CUTOUT;
        final MergedConfiguration mMergedConfiguration = new MergedConfiguration();

        final WindowManager.LayoutParams mLayout
                = new WindowManager.LayoutParams();
        IWindowSession mSession;
        InputChannel mInputChannel;

        final Object mLock = new Object();
        boolean mOffsetMessageEnqueued;
        float mPendingXOffset;
        float mPendingYOffset;
        float mPendingXOffsetStep;
        float mPendingYOffsetStep;
        boolean mPendingSync;
        MotionEvent mPendingMove;
        boolean mIsInAmbientMode;

        // Needed for throttling onComputeColors.
        private long mLastColorInvalidation;
        private final Runnable mNotifyColorsChanged = this::notifyColorsChanged;
        private final Supplier<Long> mClockFunction;
        private final Handler mHandler;

        DisplayManager mDisplayManager;
        Display mDisplay;
        private int mDisplayState;

        final BaseSurfaceHolder mSurfaceHolder = new BaseSurfaceHolder() {
            {
                mRequestedFormat = PixelFormat.RGBX_8888;
            }

            @Override
            public boolean onAllowLockCanvas() {
                return mDrawingAllowed;
            }

            @Override
            public void onRelayoutContainer() {
                Message msg = mCaller.obtainMessage(MSG_UPDATE_SURFACE);
                mCaller.sendMessage(msg);
            }

            @Override
            public void onUpdateSurface() {
                Message msg = mCaller.obtainMessage(MSG_UPDATE_SURFACE);
                mCaller.sendMessage(msg);
            }

            public boolean isCreating() {
                return mIsCreating;
            }

            @Override
            public void setFixedSize(int width, int height) {
                if (!mFixedSizeAllowed) {
                    // Regular apps can't do this.  It can only work for
                    // certain designs of window animations, so you can't
                    // rely on it.
                    throw new UnsupportedOperationException(
                            "Wallpapers currently only support sizing from layout");
                }
                super.setFixedSize(width, height);
            }
            
            public void setKeepScreenOn(boolean screenOn) {
                throw new UnsupportedOperationException(
                        "Wallpapers do not support keep screen on");
            }

            private void prepareToDraw() {
                if (mDisplayState == Display.STATE_DOZE
                        || mDisplayState == Display.STATE_DOZE_SUSPEND) {
                    try {
                        mSession.pokeDrawLock(mWindow);
                    } catch (RemoteException e) {
                        // System server died, can be ignored.
                    }
                }
            }

            @Override
            public Canvas lockCanvas() {
                prepareToDraw();
                return super.lockCanvas();
            }

            @Override
            public Canvas lockCanvas(Rect dirty) {
                prepareToDraw();
                return super.lockCanvas(dirty);
            }

            @Override
            public Canvas lockHardwareCanvas() {
                prepareToDraw();
                return super.lockHardwareCanvas();
            }
        };

        final class WallpaperInputEventReceiver extends InputEventReceiver {
            public WallpaperInputEventReceiver(InputChannel inputChannel, Looper looper) {
                super(inputChannel, looper);
            }

            @Override
            public void onInputEvent(InputEvent event, int displayId) {
                boolean handled = false;
                try {
                    if (event instanceof MotionEvent
                            && (event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) {
                        MotionEvent dup = MotionEvent.obtainNoHistory((MotionEvent)event);
                        dispatchPointer(dup);
                        handled = true;
                    }
                } finally {
                    finishInputEvent(event, handled);
                }
            }
        }
        WallpaperInputEventReceiver mInputEventReceiver;

        final BaseIWindow mWindow = new BaseIWindow() {
            @Override
            public void resized(Rect frame, Rect overscanInsets, Rect contentInsets,
                    Rect visibleInsets, Rect stableInsets, Rect outsets, boolean reportDraw,
                    MergedConfiguration mergedConfiguration, Rect backDropRect, boolean forceLayout,
                    boolean alwaysConsumeNavBar, int displayId,
                    DisplayCutout.ParcelableWrapper displayCutout) {
                Message msg = mCaller.obtainMessageIO(MSG_WINDOW_RESIZED,
                        reportDraw ? 1 : 0, outsets);
                mCaller.sendMessage(msg);
            }

            @Override
            public void moved(int newX, int newY) {
                Message msg = mCaller.obtainMessageII(MSG_WINDOW_MOVED, newX, newY);
                mCaller.sendMessage(msg);
            }

            @Override
            public void dispatchAppVisibility(boolean visible) {
                // We don't do this in preview mode; we'll let the preview
                // activity tell us when to run.
                if (!mIWallpaperEngine.mIsPreview) {
                    Message msg = mCaller.obtainMessageI(MSG_VISIBILITY_CHANGED,
                            visible ? 1 : 0);
                    mCaller.sendMessage(msg);
                }
            }

            @Override
            public void dispatchWallpaperOffsets(float x, float y, float xStep, float yStep,
                    boolean sync) {
                synchronized (mLock) {
                    if (DEBUG) Log.v(TAG, "Dispatch wallpaper offsets: " + x + ", " + y);
                    mPendingXOffset = x;
                    mPendingYOffset = y;
                    mPendingXOffsetStep = xStep;
                    mPendingYOffsetStep = yStep;
                    if (sync) {
                        mPendingSync = true;
                    }
                    if (!mOffsetMessageEnqueued) {
                        mOffsetMessageEnqueued = true;
                        Message msg = mCaller.obtainMessage(MSG_WALLPAPER_OFFSETS);
                        mCaller.sendMessage(msg);
                    }
                }
            }

            @Override
            public void dispatchWallpaperCommand(String action, int x, int y,
                    int z, Bundle extras, boolean sync) {
                synchronized (mLock) {
                    if (DEBUG) Log.v(TAG, "Dispatch wallpaper command: " + x + ", " + y);
                    WallpaperCommand cmd = new WallpaperCommand();
                    cmd.action = action;
                    cmd.x = x;
                    cmd.y = y;
                    cmd.z = z;
                    cmd.extras = extras;
                    cmd.sync = sync;
                    Message msg = mCaller.obtainMessage(MSG_WALLPAPER_COMMAND);
                    msg.obj = cmd;
                    mCaller.sendMessage(msg);
                }
            }
        };

        Default constructor
/**
         * Default constructor
         */
        public Engine() {
            this(SystemClock::elapsedRealtime, Handler.getMain());
        }

        Constructor used for test purposes.
Params: clockFunction – Supplies current times in millis.
handler – Used for posting/deferring asynchronous calls.
@hide /**
         * Constructor used for test purposes.
         *
         * @param clockFunction Supplies current times in millis.
         * @param handler Used for posting/deferring asynchronous calls.
         * @hide
         */
        @VisibleForTesting
        public Engine(Supplier<Long> clockFunction, Handler handler) {
           mClockFunction = clockFunction;
           mHandler = handler;
        }
        
        Provides access to the surface in which this wallpaper is drawn.
/**
         * Provides access to the surface in which this wallpaper is drawn.
         */
        public SurfaceHolder getSurfaceHolder() {
            return mSurfaceHolder;
        }
        
        Convenience for 
WallpaperManager.getDesiredMinimumWidth(), returning the width that the system would like this wallpaper to run in. /**
         * Convenience for {@link WallpaperManager#getDesiredMinimumWidth()
         * WallpaperManager.getDesiredMinimumWidth()}, returning the width
         * that the system would like this wallpaper to run in.
         */
        public int getDesiredMinimumWidth() {
            return mIWallpaperEngine.mReqWidth;
        }
        
        Convenience for 
WallpaperManager.getDesiredMinimumHeight(), returning the height that the system would like this wallpaper to run in. /**
         * Convenience for {@link WallpaperManager#getDesiredMinimumHeight()
         * WallpaperManager.getDesiredMinimumHeight()}, returning the height
         * that the system would like this wallpaper to run in.
         */
        public int getDesiredMinimumHeight() {
            return mIWallpaperEngine.mReqHeight;
        }
        
        Return whether the wallpaper is currently visible to the user, this is the last value supplied to onVisibilityChanged(boolean). /**
         * Return whether the wallpaper is currently visible to the user,
         * this is the last value supplied to
         * {@link #onVisibilityChanged(boolean)}.
         */
        public boolean isVisible() {
            return mReportedVisible;
        }
        
        Returns true if this engine is running in preview mode -- that is,
it is being shown to the user before they select it as the actual
wallpaper.
/**
         * Returns true if this engine is running in preview mode -- that is,
         * it is being shown to the user before they select it as the actual
         * wallpaper.
         */
        public boolean isPreview() {
            return mIWallpaperEngine.mIsPreview;
        }

        Returns true if this engine is running in ambient mode -- that is,
it is being shown in low power mode, in always on display.
@hide /**
         * Returns true if this engine is running in ambient mode -- that is,
         * it is being shown in low power mode, in always on display.
         * @hide
         */
        public boolean isInAmbientMode() {
            return mIsInAmbientMode;
        }
        
        Control whether this wallpaper will receive raw touch events from the window manager as the user interacts with the window that is currently displaying the wallpaper. By default they are turned off. If enabled, the events will be received in onTouchEvent(MotionEvent). /**
         * Control whether this wallpaper will receive raw touch events
         * from the window manager as the user interacts with the window
         * that is currently displaying the wallpaper.  By default they
         * are turned off.  If enabled, the events will be received in
         * {@link #onTouchEvent(MotionEvent)}.
         */
        public void setTouchEventsEnabled(boolean enabled) {
            mWindowFlags = enabled
                    ? (mWindowFlags&~WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE)
                    : (mWindowFlags|WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
            if (mCreated) {
                updateSurface(false, false, false);
            }
        }

        Control whether this wallpaper will receive notifications when the wallpaper
has been scrolled. By default, wallpapers will receive notifications, although
the default static image wallpapers do not. It is a performance optimization to
set this to false.
Params: enabled – whether the wallpaper wants to receive offset notifications/**
         * Control whether this wallpaper will receive notifications when the wallpaper
         * has been scrolled. By default, wallpapers will receive notifications, although
         * the default static image wallpapers do not. It is a performance optimization to
         * set this to false.
         *
         * @param enabled whether the wallpaper wants to receive offset notifications
         */
        public void setOffsetNotificationsEnabled(boolean enabled) {
            mWindowPrivateFlags = enabled
                    ? (mWindowPrivateFlags |
                        WindowManager.LayoutParams.PRIVATE_FLAG_WANTS_OFFSET_NOTIFICATIONS)
                    : (mWindowPrivateFlags &
                        ~WindowManager.LayoutParams.PRIVATE_FLAG_WANTS_OFFSET_NOTIFICATIONS);
            if (mCreated) {
                updateSurface(false, false, false);
            }
        }

        {@hide} /** {@hide} */
        public void setFixedSizeAllowed(boolean allowed) {
            mFixedSizeAllowed = allowed;
        }

        Called once to initialize the engine.  After returning, the
engine's surface will be created by the framework.
/**
         * Called once to initialize the engine.  After returning, the
         * engine's surface will be created by the framework.
         */
        public void onCreate(SurfaceHolder surfaceHolder) {
        }

        Called right before the engine is going away.  After this the
surface will be destroyed and this Engine object is no longer
valid.
/**
         * Called right before the engine is going away.  After this the
         * surface will be destroyed and this Engine object is no longer
         * valid.
         */
        public void onDestroy() {
        }

        Called to inform you of the wallpaper becoming visible or
hidden.  It is very important that a wallpaper only use
CPU while it is visible..
/**
         * Called to inform you of the wallpaper becoming visible or
         * hidden.  <em>It is very important that a wallpaper only use
         * CPU while it is visible.</em>.
         */
        public void onVisibilityChanged(boolean visible) {
        }

        Called with the current insets that are in effect for the wallpaper.
This gives you the part of the overall wallpaper surface that will
generally be visible to the user (ignoring position offsets applied to it).
Params: insets – Insets to apply./**
         * Called with the current insets that are in effect for the wallpaper.
         * This gives you the part of the overall wallpaper surface that will
         * generally be visible to the user (ignoring position offsets applied to it).
         *
         * @param insets Insets to apply.
         */
        public void onApplyWindowInsets(WindowInsets insets) {
        }

        Called as the user performs touch-screen interaction with the
window that is currently showing this wallpaper.  Note that the
events you receive here are driven by the actual application the
user is interacting with, so if it is slow you will get fewer
move events.
/**
         * Called as the user performs touch-screen interaction with the
         * window that is currently showing this wallpaper.  Note that the
         * events you receive here are driven by the actual application the
         * user is interacting with, so if it is slow you will get fewer
         * move events.
         */
        public void onTouchEvent(MotionEvent event) {
        }

        Called to inform you of the wallpaper's offsets changing within its contain, corresponding to the container's call to 
WallpaperManager.setWallpaperOffsets(). /**
         * Called to inform you of the wallpaper's offsets changing
         * within its contain, corresponding to the container's
         * call to {@link WallpaperManager#setWallpaperOffsets(IBinder, float, float)
         * WallpaperManager.setWallpaperOffsets()}.
         */
        public void onOffsetsChanged(float xOffset, float yOffset,
                float xOffsetStep, float yOffsetStep,
                int xPixelOffset, int yPixelOffset) {
        }

        Process a command that was sent to the wallpaper with WallpaperManager.sendWallpaperCommand. The default implementation does nothing, and always returns null as the result. 
Params: action – The name of the command to perform.  This tells you
what to do and how to interpret the rest of the arguments.
x – Generic integer parameter.
y – Generic integer parameter.
z – Generic integer parameter.
extras – Any additional parameters.
resultRequested – If true, the caller is requesting that
a result, appropriate for the command, be returned back.
Returns: If returning a result, create a Bundle and place the
result data in to it.  Otherwise return null./**
         * Process a command that was sent to the wallpaper with
         * {@link WallpaperManager#sendWallpaperCommand}.
         * The default implementation does nothing, and always returns null
         * as the result.
         * 
         * @param action The name of the command to perform.  This tells you
         * what to do and how to interpret the rest of the arguments.
         * @param x Generic integer parameter.
         * @param y Generic integer parameter.
         * @param z Generic integer parameter.
         * @param extras Any additional parameters.
         * @param resultRequested If true, the caller is requesting that
         * a result, appropriate for the command, be returned back.
         * @return If returning a result, create a Bundle and place the
         * result data in to it.  Otherwise return null.
         */
        public Bundle onCommand(String action, int x, int y, int z,
                Bundle extras, boolean resultRequested) {
            return null;
        }

        Called when the device enters or exits ambient mode.
Params: inAmbientMode – true if in ambient mode.
animated – true if you'll have te opportunity of animating your transition false when the screen will blank and the wallpaper should be set to ambient mode immediately.
@hide /**
         * Called when the device enters or exits ambient mode.
         *
         * @param inAmbientMode {@code true} if in ambient mode.
         * @param animated {@code true} if you'll have te opportunity of animating your transition
         *                 {@code false} when the screen will blank and the wallpaper should be
         *                 set to ambient mode immediately.
         * @hide
         */
        public void onAmbientModeChanged(boolean inAmbientMode, boolean animated) {
        }

        Called when an application has changed the desired virtual size of
the wallpaper.
/**
         * Called when an application has changed the desired virtual size of
         * the wallpaper.
         */
        public void onDesiredSizeChanged(int desiredWidth, int desiredHeight) {
        }

        Convenience for 
SurfaceHolder.Callback.surfaceChanged(). /**
         * Convenience for {@link SurfaceHolder.Callback#surfaceChanged
         * SurfaceHolder.Callback.surfaceChanged()}.
         */
        public void onSurfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        }

        Convenience for 
SurfaceHolder.Callback.surfaceRedrawNeeded(). /**
         * Convenience for {@link SurfaceHolder.Callback2#surfaceRedrawNeeded
         * SurfaceHolder.Callback.surfaceRedrawNeeded()}.
         */
        public void onSurfaceRedrawNeeded(SurfaceHolder holder) {
        }

        Convenience for 
SurfaceHolder.Callback.surfaceCreated(). /**
         * Convenience for {@link SurfaceHolder.Callback#surfaceCreated
         * SurfaceHolder.Callback.surfaceCreated()}.
         */
        public void onSurfaceCreated(SurfaceHolder holder) {
        }

        Convenience for 
SurfaceHolder.Callback.surfaceDestroyed(). /**
         * Convenience for {@link SurfaceHolder.Callback#surfaceDestroyed
         * SurfaceHolder.Callback.surfaceDestroyed()}.
         */
        public void onSurfaceDestroyed(SurfaceHolder holder) {
        }

        Notifies the engine that wallpaper colors changed significantly. This will trigger a onComputeColors() call. /**
         * Notifies the engine that wallpaper colors changed significantly.
         * This will trigger a {@link #onComputeColors()} call.
         */
        public void notifyColorsChanged() {
            final long now = mClockFunction.get();
            if (now - mLastColorInvalidation < NOTIFY_COLORS_RATE_LIMIT_MS) {
                Log.w(TAG, "This call has been deferred. You should only call "
                        + "notifyColorsChanged() once every "
                        + (NOTIFY_COLORS_RATE_LIMIT_MS / 1000f) + " seconds.");
                if (!mHandler.hasCallbacks(mNotifyColorsChanged)) {
                    mHandler.postDelayed(mNotifyColorsChanged, NOTIFY_COLORS_RATE_LIMIT_MS);
                }
                return;
            }
            mLastColorInvalidation = now;
            mHandler.removeCallbacks(mNotifyColorsChanged);

            try {
                final WallpaperColors newColors = onComputeColors();
                if (mConnection != null) {
                    mConnection.onWallpaperColorsChanged(newColors);
                } else {
                    Log.w(TAG, "Can't notify system because wallpaper connection "
                            + "was not established.");
                }
            } catch (RemoteException e) {
                Log.w(TAG, "Can't notify system because wallpaper connection was lost.", e);
            }
        }

        Called by the system when it needs to know what colors the wallpaper is using. You might return null if no color information is available at the moment. In that case you might want to call notifyColorsChanged() when color information becomes available.  The simplest way of creating a WallpaperColors object is by using WallpaperColors.fromBitmap(Bitmap) or WallpaperColors.fromDrawable(Drawable), but you can also specify your main colors by constructing a WallpaperColors object manually. 
Returns: Wallpaper colors./**
         * Called by the system when it needs to know what colors the wallpaper is using.
         * You might return null if no color information is available at the moment.
         * In that case you might want to call {@link #notifyColorsChanged()} when
         * color information becomes available.
         * <p>
         * The simplest way of creating a {@link android.app.WallpaperColors} object is by using
         * {@link android.app.WallpaperColors#fromBitmap(Bitmap)} or
         * {@link android.app.WallpaperColors#fromDrawable(Drawable)}, but you can also specify
         * your main colors by constructing a {@link android.app.WallpaperColors} object manually.
         *
         * @return Wallpaper colors.
         */
        public @Nullable WallpaperColors onComputeColors() {
            return null;
        }

        Sets internal engine state. Only for testing.
Params: created – true or false.
@hide /**
         * Sets internal engine state. Only for testing.
         * @param created {@code true} or {@code false}.
         * @hide
         */
        @VisibleForTesting
        public void setCreated(boolean created) {
            mCreated = created;
        }

        protected void dump(String prefix, FileDescriptor fd, PrintWriter out, String[] args) {
            out.print(prefix); out.print("mInitializing="); out.print(mInitializing);
                    out.print(" mDestroyed="); out.println(mDestroyed);
            out.print(prefix); out.print("mVisible="); out.print(mVisible);
                    out.print(" mReportedVisible="); out.println(mReportedVisible);
            out.print(prefix); out.print("mDisplay="); out.println(mDisplay);
            out.print(prefix); out.print("mCreated="); out.print(mCreated);
                    out.print(" mSurfaceCreated="); out.print(mSurfaceCreated);
                    out.print(" mIsCreating="); out.print(mIsCreating);
                    out.print(" mDrawingAllowed="); out.println(mDrawingAllowed);
            out.print(prefix); out.print("mWidth="); out.print(mWidth);
                    out.print(" mCurWidth="); out.print(mCurWidth);
                    out.print(" mHeight="); out.print(mHeight);
                    out.print(" mCurHeight="); out.println(mCurHeight);
            out.print(prefix); out.print("mType="); out.print(mType);
                    out.print(" mWindowFlags="); out.print(mWindowFlags);
                    out.print(" mCurWindowFlags="); out.println(mCurWindowFlags);
            out.print(prefix); out.print("mWindowPrivateFlags="); out.print(mWindowPrivateFlags);
                    out.print(" mCurWindowPrivateFlags="); out.println(mCurWindowPrivateFlags);
            out.print(prefix); out.print("mVisibleInsets=");
                    out.print(mVisibleInsets.toShortString());
                    out.print(" mWinFrame="); out.print(mWinFrame.toShortString());
                    out.print(" mContentInsets="); out.println(mContentInsets.toShortString());
            out.print(prefix); out.print("mConfiguration=");
                    out.println(mMergedConfiguration.getMergedConfiguration());
            out.print(prefix); out.print("mLayout="); out.println(mLayout);
            synchronized (mLock) {
                out.print(prefix); out.print("mPendingXOffset="); out.print(mPendingXOffset);
                        out.print(" mPendingXOffset="); out.println(mPendingXOffset);
                out.print(prefix); out.print("mPendingXOffsetStep=");
                        out.print(mPendingXOffsetStep);
                        out.print(" mPendingXOffsetStep="); out.println(mPendingXOffsetStep);
                out.print(prefix); out.print("mOffsetMessageEnqueued=");
                        out.print(mOffsetMessageEnqueued);
                        out.print(" mPendingSync="); out.println(mPendingSync);
                if (mPendingMove != null) {
                    out.print(prefix); out.print("mPendingMove="); out.println(mPendingMove);
                }
            }
        }

        private void dispatchPointer(MotionEvent event) {
            if (event.isTouchEvent()) {
                synchronized (mLock) {
                    if (event.getAction() == MotionEvent.ACTION_MOVE) {
                        mPendingMove = event;
                    } else {
                        mPendingMove = null;
                    }
                }
                Message msg = mCaller.obtainMessageO(MSG_TOUCH_EVENT, event);
                mCaller.sendMessage(msg);
            } else {
                event.recycle();
            }
        }

        void updateSurface(boolean forceRelayout, boolean forceReport, boolean redrawNeeded) {
            if (mDestroyed) {
                Log.w(TAG, "Ignoring updateSurface: destroyed");
            }

            boolean fixedSize = false;
            int myWidth = mSurfaceHolder.getRequestedWidth();
            if (myWidth <= 0) myWidth = ViewGroup.LayoutParams.MATCH_PARENT;
            else fixedSize = true;
            int myHeight = mSurfaceHolder.getRequestedHeight();
            if (myHeight <= 0) myHeight = ViewGroup.LayoutParams.MATCH_PARENT;
            else fixedSize = true;

            final boolean creating = !mCreated;
            final boolean surfaceCreating = !mSurfaceCreated;
            final boolean formatChanged = mFormat != mSurfaceHolder.getRequestedFormat();
            boolean sizeChanged = mWidth != myWidth || mHeight != myHeight;
            boolean insetsChanged = !mCreated;
            final boolean typeChanged = mType != mSurfaceHolder.getRequestedType();
            final boolean flagsChanged = mCurWindowFlags != mWindowFlags ||
                    mCurWindowPrivateFlags != mWindowPrivateFlags;
            if (forceRelayout || creating || surfaceCreating || formatChanged || sizeChanged
                    || typeChanged || flagsChanged || redrawNeeded
                    || !mIWallpaperEngine.mShownReported) {

                if (DEBUG) Log.v(TAG, "Changes: creating=" + creating
                        + " format=" + formatChanged + " size=" + sizeChanged);

                try {
                    mWidth = myWidth;
                    mHeight = myHeight;
                    mFormat = mSurfaceHolder.getRequestedFormat();
                    mType = mSurfaceHolder.getRequestedType();

                    mLayout.x = 0;
                    mLayout.y = 0;
                    mLayout.width = myWidth;
                    mLayout.height = myHeight;
                    
                    mLayout.format = mFormat;
                    
                    mCurWindowFlags = mWindowFlags;
                    mLayout.flags = mWindowFlags
                            | WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS
                            | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR
                            | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
                            | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
                    mCurWindowPrivateFlags = mWindowPrivateFlags;
                    mLayout.privateFlags = mWindowPrivateFlags;

                    mLayout.memoryType = mType;
                    mLayout.token = mWindowToken;

                    if (!mCreated) {
                        // Retrieve watch round info
                        TypedArray windowStyle = obtainStyledAttributes(
                                com.android.internal.R.styleable.Window);
                        windowStyle.recycle();

                        // Add window
                        mLayout.type = mIWallpaperEngine.mWindowType;
                        mLayout.gravity = Gravity.START|Gravity.TOP;
                        mLayout.setTitle(WallpaperService.this.getClass().getName());
                        mLayout.windowAnimations =
                                com.android.internal.R.style.Animation_Wallpaper;
                        mInputChannel = new InputChannel();
                        if (mSession.addToDisplay(mWindow, mWindow.mSeq, mLayout, View.VISIBLE,
                                Display.DEFAULT_DISPLAY, mWinFrame, mContentInsets, mStableInsets,
                                mOutsets, mDisplayCutout, mInputChannel) < 0) {
                            Log.w(TAG, "Failed to add window while updating wallpaper surface.");
                            return;
                        }
                        mCreated = true;

                        mInputEventReceiver = new WallpaperInputEventReceiver(
                                mInputChannel, Looper.myLooper());
                    }

                    mSurfaceHolder.mSurfaceLock.lock();
                    mDrawingAllowed = true;

                    if (!fixedSize) {
                        mLayout.surfaceInsets.set(mIWallpaperEngine.mDisplayPadding);
                        mLayout.surfaceInsets.left += mOutsets.left;
                        mLayout.surfaceInsets.top += mOutsets.top;
                        mLayout.surfaceInsets.right += mOutsets.right;
                        mLayout.surfaceInsets.bottom += mOutsets.bottom;
                    } else {
                        mLayout.surfaceInsets.set(0, 0, 0, 0);
                    }
                    final int relayoutResult = mSession.relayout(
                        mWindow, mWindow.mSeq, mLayout, mWidth, mHeight,
                            View.VISIBLE, 0, -1, mWinFrame, mOverscanInsets, mContentInsets,
                            mVisibleInsets, mStableInsets, mOutsets, mBackdropFrame,
                            mDisplayCutout, mMergedConfiguration, mSurfaceHolder.mSurface);

                    if (DEBUG) Log.v(TAG, "New surface: " + mSurfaceHolder.mSurface
                            + ", frame=" + mWinFrame);

                    int w = mWinFrame.width();
                    int h = mWinFrame.height();

                    if (!fixedSize) {
                        final Rect padding = mIWallpaperEngine.mDisplayPadding;
                        w += padding.left + padding.right + mOutsets.left + mOutsets.right;
                        h += padding.top + padding.bottom + mOutsets.top + mOutsets.bottom;
                        mOverscanInsets.left += padding.left;
                        mOverscanInsets.top += padding.top;
                        mOverscanInsets.right += padding.right;
                        mOverscanInsets.bottom += padding.bottom;
                        mContentInsets.left += padding.left;
                        mContentInsets.top += padding.top;
                        mContentInsets.right += padding.right;
                        mContentInsets.bottom += padding.bottom;
                        mStableInsets.left += padding.left;
                        mStableInsets.top += padding.top;
                        mStableInsets.right += padding.right;
                        mStableInsets.bottom += padding.bottom;
                        mDisplayCutout.set(mDisplayCutout.get().inset(-padding.left, -padding.top,
                                -padding.right, -padding.bottom));
                    }

                    if (mCurWidth != w) {
                        sizeChanged = true;
                        mCurWidth = w;
                    }
                    if (mCurHeight != h) {
                        sizeChanged = true;
                        mCurHeight = h;
                    }

                    if (DEBUG) {
                        Log.v(TAG, "Wallpaper size has changed: (" + mCurWidth + ", " + mCurHeight);
                    }

                    insetsChanged |= !mDispatchedOverscanInsets.equals(mOverscanInsets);
                    insetsChanged |= !mDispatchedContentInsets.equals(mContentInsets);
                    insetsChanged |= !mDispatchedStableInsets.equals(mStableInsets);
                    insetsChanged |= !mDispatchedOutsets.equals(mOutsets);
                    insetsChanged |= !mDispatchedDisplayCutout.equals(mDisplayCutout.get());

                    mSurfaceHolder.setSurfaceFrameSize(w, h);
                    mSurfaceHolder.mSurfaceLock.unlock();

                    if (!mSurfaceHolder.mSurface.isValid()) {
                        reportSurfaceDestroyed();
                        if (DEBUG) Log.v(TAG, "Layout: Surface destroyed");
                        return;
                    }

                    boolean didSurface = false;

                    try {
                        mSurfaceHolder.ungetCallbacks();

                        if (surfaceCreating) {
                            mIsCreating = true;
                            didSurface = true;
                            if (DEBUG) Log.v(TAG, "onSurfaceCreated("
                                    + mSurfaceHolder + "): " + this);
                            onSurfaceCreated(mSurfaceHolder);
                            SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks();
                            if (callbacks != null) {
                                for (SurfaceHolder.Callback c : callbacks) {
                                    c.surfaceCreated(mSurfaceHolder);
                                }
                            }
                        }

                        redrawNeeded |= creating || (relayoutResult
                                & WindowManagerGlobal.RELAYOUT_RES_FIRST_TIME) != 0;

                        if (forceReport || creating || surfaceCreating
                                || formatChanged || sizeChanged) {
                            if (DEBUG) {
                                RuntimeException e = new RuntimeException();
                                e.fillInStackTrace();
                                Log.w(TAG, "forceReport=" + forceReport + " creating=" + creating
                                        + " formatChanged=" + formatChanged
                                        + " sizeChanged=" + sizeChanged, e);
                            }
                            if (DEBUG) Log.v(TAG, "onSurfaceChanged("
                                    + mSurfaceHolder + ", " + mFormat
                                    + ", " + mCurWidth + ", " + mCurHeight
                                    + "): " + this);
                            didSurface = true;
                            onSurfaceChanged(mSurfaceHolder, mFormat,
                                    mCurWidth, mCurHeight);
                            SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks();
                            if (callbacks != null) {
                                for (SurfaceHolder.Callback c : callbacks) {
                                    c.surfaceChanged(mSurfaceHolder, mFormat,
                                            mCurWidth, mCurHeight);
                                }
                            }
                        }

                        if (insetsChanged) {
                            mDispatchedOverscanInsets.set(mOverscanInsets);
                            mDispatchedOverscanInsets.left += mOutsets.left;
                            mDispatchedOverscanInsets.top += mOutsets.top;
                            mDispatchedOverscanInsets.right += mOutsets.right;
                            mDispatchedOverscanInsets.bottom += mOutsets.bottom;
                            mDispatchedContentInsets.set(mContentInsets);
                            mDispatchedStableInsets.set(mStableInsets);
                            mDispatchedOutsets.set(mOutsets);
                            mDispatchedDisplayCutout = mDisplayCutout.get();
                            mFinalSystemInsets.set(mDispatchedOverscanInsets);
                            mFinalStableInsets.set(mDispatchedStableInsets);
                            WindowInsets insets = new WindowInsets(mFinalSystemInsets,
                                    null, mFinalStableInsets,
                                    getResources().getConfiguration().isScreenRound(), false,
                                    mDispatchedDisplayCutout);
                            if (DEBUG) {
                                Log.v(TAG, "dispatching insets=" + insets);
                            }
                            onApplyWindowInsets(insets);
                        }

                        if (redrawNeeded) {
                            onSurfaceRedrawNeeded(mSurfaceHolder);
                            SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks();
                            if (callbacks != null) {
                                for (SurfaceHolder.Callback c : callbacks) {
                                    if (c instanceof SurfaceHolder.Callback2) {
                                        ((SurfaceHolder.Callback2)c).surfaceRedrawNeeded(
                                                mSurfaceHolder);
                                    }
                                }
                            }
                        }

                        if (didSurface && !mReportedVisible) {
                            // This wallpaper is currently invisible, but its
                            // surface has changed.  At this point let's tell it
                            // again that it is invisible in case the report about
                            // the surface caused it to start running.  We really
                            // don't want wallpapers running when not visible.
                            if (mIsCreating) {
                                // Some wallpapers will ignore this call if they
                                // had previously been told they were invisble,
                                // so if we are creating a new surface then toggle
                                // the state to get them to notice.
                                if (DEBUG) Log.v(TAG, "onVisibilityChanged(true) at surface: "
                                        + this);
                                onVisibilityChanged(true);
                            }
                            if (DEBUG) Log.v(TAG, "onVisibilityChanged(false) at surface: "
                                        + this);
                            onVisibilityChanged(false);
                        }

                    } finally {
                        mIsCreating = false;
                        mSurfaceCreated = true;
                        if (redrawNeeded) {
                            mSession.finishDrawing(mWindow);
                        }
                        mIWallpaperEngine.reportShown();
                    }
                } catch (RemoteException ex) {
                }
                if (DEBUG) Log.v(
                    TAG, "Layout: x=" + mLayout.x + " y=" + mLayout.y +
                    " w=" + mLayout.width + " h=" + mLayout.height);
            }
        }

        void attach(IWallpaperEngineWrapper wrapper) {
            if (DEBUG) Log.v(TAG, "attach: " + this + " wrapper=" + wrapper);
            if (mDestroyed) {
                return;
            }
            
            mIWallpaperEngine = wrapper;
            mCaller = wrapper.mCaller;
            mConnection = wrapper.mConnection;
            mWindowToken = wrapper.mWindowToken;
            mSurfaceHolder.setSizeFromLayout();
            mInitializing = true;
            mSession = WindowManagerGlobal.getWindowSession();
            
            mWindow.setSession(mSession);

            mLayout.packageName = getPackageName();

            mDisplayManager = (DisplayManager)getSystemService(Context.DISPLAY_SERVICE);
            mDisplayManager.registerDisplayListener(mDisplayListener, mCaller.getHandler());
            mDisplay = mDisplayManager.getDisplay(Display.DEFAULT_DISPLAY);
            mDisplayState = mDisplay.getState();

            if (DEBUG) Log.v(TAG, "onCreate(): " + this);
            onCreate(mSurfaceHolder);
            
            mInitializing = false;
            mReportedVisible = false;
            updateSurface(false, false, false);
        }

        Executes life cycle event and updates internal ambient mode state based on
message sent from handler.
Params: inAmbientMode – true if in ambient mode.
animated – true if the transition will be animated.
@hide /**
         * Executes life cycle event and updates internal ambient mode state based on
         * message sent from handler.
         *
         * @param inAmbientMode {@code true} if in ambient mode.
         * @param animated {@code true} if the transition will be animated.
         * @hide
         */
        @VisibleForTesting
        public void doAmbientModeChanged(boolean inAmbientMode, boolean animated) {
            if (!mDestroyed) {
                if (DEBUG) {
                    Log.v(TAG, "onAmbientModeChanged(" + inAmbientMode + ", "
                            + animated + "): " + this);
                }
                mIsInAmbientMode = inAmbientMode;
                if (mCreated) {
                    onAmbientModeChanged(inAmbientMode, animated);
                }
            }
        }

        void doDesiredSizeChanged(int desiredWidth, int desiredHeight) {
            if (!mDestroyed) {
                if (DEBUG) Log.v(TAG, "onDesiredSizeChanged("
                        + desiredWidth + "," + desiredHeight + "): " + this);
                mIWallpaperEngine.mReqWidth = desiredWidth;
                mIWallpaperEngine.mReqHeight = desiredHeight;
                onDesiredSizeChanged(desiredWidth, desiredHeight);
                doOffsetsChanged(true);
            }
        }

        void doDisplayPaddingChanged(Rect padding) {
            if (!mDestroyed) {
                if (DEBUG) Log.v(TAG, "onDisplayPaddingChanged(" + padding + "): " + this);
                if (!mIWallpaperEngine.mDisplayPadding.equals(padding)) {
                    mIWallpaperEngine.mDisplayPadding.set(padding);
                    updateSurface(true, false, false);
                }
            }
        }

        void doVisibilityChanged(boolean visible) {
            if (!mDestroyed) {
                mVisible = visible;
                reportVisibility();
            }
        }

        void reportVisibility() {
            if (!mDestroyed) {
                mDisplayState = mDisplay == null ? Display.STATE_UNKNOWN : mDisplay.getState();
                boolean visible = mVisible && mDisplayState != Display.STATE_OFF;
                if (mReportedVisible != visible) {
                    mReportedVisible = visible;
                    if (DEBUG) Log.v(TAG, "onVisibilityChanged(" + visible
                            + "): " + this);
                    if (visible) {
                        // If becoming visible, in preview mode the surface
                        // may have been destroyed so now we need to make
                        // sure it is re-created.
                        doOffsetsChanged(false);
                        updateSurface(false, false, false);
                    }
                    onVisibilityChanged(visible);
                }
            }
        }
        
        void doOffsetsChanged(boolean always) {
            if (mDestroyed) {
                return;
            }

            if (!always && !mOffsetsChanged) {
                return;
            }

            float xOffset;
            float yOffset;
            float xOffsetStep;
            float yOffsetStep;
            boolean sync;
            synchronized (mLock) {
                xOffset = mPendingXOffset;
                yOffset = mPendingYOffset;
                xOffsetStep = mPendingXOffsetStep;
                yOffsetStep = mPendingYOffsetStep;
                sync = mPendingSync;
                mPendingSync = false;
                mOffsetMessageEnqueued = false;
            }

            if (mSurfaceCreated) {
                if (mReportedVisible) {
                    if (DEBUG) Log.v(TAG, "Offsets change in " + this
                            + ": " + xOffset + "," + yOffset);
                    final int availw = mIWallpaperEngine.mReqWidth-mCurWidth;
                    final int xPixels = availw > 0 ? -(int)(availw*xOffset+.5f) : 0;
                    final int availh = mIWallpaperEngine.mReqHeight-mCurHeight;
                    final int yPixels = availh > 0 ? -(int)(availh*yOffset+.5f) : 0;
                    onOffsetsChanged(xOffset, yOffset, xOffsetStep, yOffsetStep, xPixels, yPixels);
                } else {
                    mOffsetsChanged = true;
                }
            }
            
            if (sync) {
                try {
                    if (DEBUG) Log.v(TAG, "Reporting offsets change complete");
                    mSession.wallpaperOffsetsComplete(mWindow.asBinder());
                } catch (RemoteException e) {
                }
            }
        }
        
        void doCommand(WallpaperCommand cmd) {
            Bundle result;
            if (!mDestroyed) {
                result = onCommand(cmd.action, cmd.x, cmd.y, cmd.z,
                        cmd.extras, cmd.sync);
            } else {
                result = null;
            }
            if (cmd.sync) {
                try {
                    if (DEBUG) Log.v(TAG, "Reporting command complete");
                    mSession.wallpaperCommandComplete(mWindow.asBinder(), result);
                } catch (RemoteException e) {
                }
            }
        }
        
        void reportSurfaceDestroyed() {
            if (mSurfaceCreated) {
                mSurfaceCreated = false;
                mSurfaceHolder.ungetCallbacks();
                SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks();
                if (callbacks != null) {
                    for (SurfaceHolder.Callback c : callbacks) {
                        c.surfaceDestroyed(mSurfaceHolder);
                    }
                }
                if (DEBUG) Log.v(TAG, "onSurfaceDestroyed("
                        + mSurfaceHolder + "): " + this);
                onSurfaceDestroyed(mSurfaceHolder);
            }
        }
        
        void detach() {
            if (mDestroyed) {
                return;
            }
            
            mDestroyed = true;

            if (mDisplayManager != null) {
                mDisplayManager.unregisterDisplayListener(mDisplayListener);
            }

            if (mVisible) {
                mVisible = false;
                if (DEBUG) Log.v(TAG, "onVisibilityChanged(false): " + this);
                onVisibilityChanged(false);
            }
            
            reportSurfaceDestroyed();
            
            if (DEBUG) Log.v(TAG, "onDestroy(): " + this);
            onDestroy();

            if (mCreated) {
                try {
                    if (DEBUG) Log.v(TAG, "Removing window and destroying surface "
                            + mSurfaceHolder.getSurface() + " of: " + this);
                    
                    if (mInputEventReceiver != null) {
                        mInputEventReceiver.dispose();
                        mInputEventReceiver = null;
                    }
                    
                    mSession.remove(mWindow);
                } catch (RemoteException e) {
                }
                mSurfaceHolder.mSurface.release();
                mCreated = false;
                
                // Dispose the input channel after removing the window so the Window Manager
                // doesn't interpret the input channel being closed as an abnormal termination.
                if (mInputChannel != null) {
                    mInputChannel.dispose();
                    mInputChannel = null;
                }
            }
        }

        private final DisplayListener mDisplayListener = new DisplayListener() {
            @Override
            public void onDisplayChanged(int displayId) {
                if (mDisplay.getDisplayId() == displayId) {
                    reportVisibility();
                }
            }

            @Override
            public void onDisplayRemoved(int displayId) {
            }

            @Override
            public void onDisplayAdded(int displayId) {
            }
        };
    }

    class IWallpaperEngineWrapper extends IWallpaperEngine.Stub
            implements HandlerCaller.Callback {
        private final HandlerCaller mCaller;

        final IWallpaperConnection mConnection;
        final IBinder mWindowToken;
        final int mWindowType;
        final boolean mIsPreview;
        boolean mShownReported;
        int mReqWidth;
        int mReqHeight;
        final Rect mDisplayPadding = new Rect();

        Engine mEngine;

        IWallpaperEngineWrapper(WallpaperService context,
                IWallpaperConnection conn, IBinder windowToken,
                int windowType, boolean isPreview, int reqWidth, int reqHeight, Rect padding) {
            mCaller = new HandlerCaller(context, context.getMainLooper(), this, true);
            mConnection = conn;
            mWindowToken = windowToken;
            mWindowType = windowType;
            mIsPreview = isPreview;
            mReqWidth = reqWidth;
            mReqHeight = reqHeight;
            mDisplayPadding.set(padding);
            
            Message msg = mCaller.obtainMessage(DO_ATTACH);
            mCaller.sendMessage(msg);
        }

        public void setDesiredSize(int width, int height) {
            Message msg = mCaller.obtainMessageII(DO_SET_DESIRED_SIZE, width, height);
            mCaller.sendMessage(msg);
        }

        public void setDisplayPadding(Rect padding) {
            Message msg = mCaller.obtainMessageO(DO_SET_DISPLAY_PADDING, padding);
            mCaller.sendMessage(msg);
        }

        public void setVisibility(boolean visible) {
            Message msg = mCaller.obtainMessageI(MSG_VISIBILITY_CHANGED,
                    visible ? 1 : 0);
            mCaller.sendMessage(msg);
        }

        @Override
        public void setInAmbientMode(boolean inAmbientDisplay, boolean animated)
                throws RemoteException {
            Message msg = mCaller.obtainMessageII(DO_IN_AMBIENT_MODE, inAmbientDisplay ? 1 : 0,
                    animated ? 1 : 0);
            mCaller.sendMessage(msg);
        }

        public void dispatchPointer(MotionEvent event) {
            if (mEngine != null) {
                mEngine.dispatchPointer(event);
            } else {
                event.recycle();
            }
        }

        public void dispatchWallpaperCommand(String action, int x, int y,
                int z, Bundle extras) {
            if (mEngine != null) {
                mEngine.mWindow.dispatchWallpaperCommand(action, x, y, z, extras, false);
            }
        }

        public void reportShown() {
            if (!mShownReported) {
                mShownReported = true;
                try {
                    mConnection.engineShown(this);
                } catch (RemoteException e) {
                    Log.w(TAG, "Wallpaper host disappeared", e);
                    return;
                }
            }
        }

        public void requestWallpaperColors() {
            Message msg = mCaller.obtainMessage(MSG_REQUEST_WALLPAPER_COLORS);
            mCaller.sendMessage(msg);
        }

        public void destroy() {
            Message msg = mCaller.obtainMessage(DO_DETACH);
            mCaller.sendMessage(msg);
        }

        @Override
        public void executeMessage(Message message) {
            switch (message.what) {
                case DO_ATTACH: {
                    try {
                        mConnection.attachEngine(this);
                    } catch (RemoteException e) {
                        Log.w(TAG, "Wallpaper host disappeared", e);
                        return;
                    }
                    Engine engine = onCreateEngine();
                    mEngine = engine;
                    mActiveEngines.add(engine);
                    engine.attach(this);
                    return;
                }
                case DO_DETACH: {
                    mActiveEngines.remove(mEngine);
                    mEngine.detach();
                    return;
                }
                case DO_SET_DESIRED_SIZE: {
                    mEngine.doDesiredSizeChanged(message.arg1, message.arg2);
                    return;
                }
                case DO_SET_DISPLAY_PADDING: {
                    mEngine.doDisplayPaddingChanged((Rect) message.obj);
                    return;
                }
                case DO_IN_AMBIENT_MODE: {
                    mEngine.doAmbientModeChanged(message.arg1 != 0, message.arg2 != 0);
                    return;
                }
                case MSG_UPDATE_SURFACE:
                    mEngine.updateSurface(true, false, false);
                    break;
                case MSG_VISIBILITY_CHANGED:
                    if (DEBUG) Log.v(TAG, "Visibility change in " + mEngine
                            + ": " + message.arg1);
                    mEngine.doVisibilityChanged(message.arg1 != 0);
                    break;
                case MSG_WALLPAPER_OFFSETS: {
                    mEngine.doOffsetsChanged(true);
                } break;
                case MSG_WALLPAPER_COMMAND: {
                    WallpaperCommand cmd = (WallpaperCommand)message.obj;
                    mEngine.doCommand(cmd);
                } break;
                case MSG_WINDOW_RESIZED: {
                    final boolean reportDraw = message.arg1 != 0;
                    mEngine.mOutsets.set((Rect) message.obj);
                    mEngine.updateSurface(true, false, reportDraw);
                    mEngine.doOffsetsChanged(true);
                } break;
                case MSG_WINDOW_MOVED: {
                    // Do nothing. What does it mean for a Wallpaper to move?
                } break;
                case MSG_TOUCH_EVENT: {
                    boolean skip = false;
                    MotionEvent ev = (MotionEvent)message.obj;
                    if (ev.getAction() == MotionEvent.ACTION_MOVE) {
                        synchronized (mEngine.mLock) {
                            if (mEngine.mPendingMove == ev) {
                                mEngine.mPendingMove = null;
                            } else {
                                // this is not the motion event we are looking for....
                                skip = true;
                            }
                        }
                    }
                    if (!skip) {
                        if (DEBUG) Log.v(TAG, "Delivering touch event: " + ev);
                        mEngine.onTouchEvent(ev);
                    }
                    ev.recycle();
                } break;
                case MSG_REQUEST_WALLPAPER_COLORS: {
                    if (mConnection == null) {
                        break;
                    }
                    try {
                        mConnection.onWallpaperColorsChanged(mEngine.onComputeColors());
                    } catch (RemoteException e) {
                        // Connection went away, nothing to do in here.
                    }
                } break;
                default :
                    Log.w(TAG, "Unknown message type " + message.what);
            }
        }
    }

    Implements the internal IWallpaperService interface to convert incoming calls to it back to calls on an WallpaperService. /**
     * Implements the internal {@link IWallpaperService} interface to convert
     * incoming calls to it back to calls on an {@link WallpaperService}.
     */
    class IWallpaperServiceWrapper extends IWallpaperService.Stub {
        private final WallpaperService mTarget;

        public IWallpaperServiceWrapper(WallpaperService context) {
            mTarget = context;
        }

        @Override
        public void attach(IWallpaperConnection conn, IBinder windowToken,
                int windowType, boolean isPreview, int reqWidth, int reqHeight, Rect padding) {
            new IWallpaperEngineWrapper(mTarget, conn, windowToken,
                    windowType, isPreview, reqWidth, reqHeight, padding);
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        for (int i=0; i<mActiveEngines.size(); i++) {
            mActiveEngines.get(i).detach();
        }
        mActiveEngines.clear();
    }

    Implement to return the implementation of the internal accessibility
service interface.  Subclasses should not override.
/**
     * Implement to return the implementation of the internal accessibility
     * service interface.  Subclasses should not override.
     */
    @Override
    public final IBinder onBind(Intent intent) {
        return new IWallpaperServiceWrapper(this);
    }

    Must be implemented to return a new instance of the wallpaper's engine.
Note that multiple instances may be active at the same time, such as
when the wallpaper is currently set as the active wallpaper and the user
is in the wallpaper picker viewing a preview of it as well.
/**
     * Must be implemented to return a new instance of the wallpaper's engine.
     * Note that multiple instances may be active at the same time, such as
     * when the wallpaper is currently set as the active wallpaper and the user
     * is in the wallpaper picker viewing a preview of it as well.
     */
    public abstract Engine onCreateEngine();

    @Override
    protected void dump(FileDescriptor fd, PrintWriter out, String[] args) {
        out.print("State of wallpaper "); out.print(this); out.println(":");
        for (int i=0; i<mActiveEngines.size(); i++) {
            Engine engine = mActiveEngines.get(i);
            out.print("  Engine "); out.print(engine); out.println(":");
            engine.dump("    ", fd, out, args);
        }
    }
}
Params:	clockFunction – Supplies current times in millis. handler – Used for posting/deferring asynchronous calls.
@hide
Params:	action – The name of the command to perform. This tells you what to do and how to interpret the rest of the arguments. x – Generic integer parameter. y – Generic integer parameter. z – Generic integer parameter. extras – Any additional parameters. resultRequested – If true, the caller is requesting that a result, appropriate for the command, be returned back.
Returns:	If returning a result, create a Bundle and place the result data in to it. Otherwise return null.
Params:	inAmbientMode – `true` if in ambient mode. animated – `true` if you'll have te opportunity of animating your transition `false` when the screen will blank and the wallpaper should be set to ambient mode immediately.
@hide
/

android/ android-9.0.0_r35/ android/service/wallpaper/WallpaperService.java
