1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.app.backup; 18 19 import android.app.WallpaperManager; 20 import android.content.Context; 21 import android.graphics.BitmapFactory; 22 import android.graphics.Point; 23 import android.os.ParcelFileDescriptor; 24 import android.util.Slog; 25 import android.view.Display; 26 import android.view.WindowManager; 27 28 import java.io.File; 29 30 /** 31 * Helper for backing up / restoring wallpapers. Basically an AbsoluteFileBackupHelper, 32 * but with logic for deciding what to do with restored wallpaper images. 33 * 34 * @hide 35 */ 36 public class WallpaperBackupHelper extends FileBackupHelperBase implements BackupHelper { 37 private static final String TAG = "WallpaperBackupHelper"; 38 private static final boolean DEBUG = false; 39 40 // This path must match what the WallpaperManagerService uses 41 // TODO: Will need to change if backing up non-primary user's wallpaper 42 public static final String WALLPAPER_IMAGE = "/data/system/users/0/wallpaper"; 43 public static final String WALLPAPER_INFO = "/data/system/users/0/wallpaper_info.xml"; 44 // Use old keys to keep legacy data compatibility and avoid writing two wallpapers 45 public static final String WALLPAPER_IMAGE_KEY = 46 "/data/data/com.android.settings/files/wallpaper"; 47 public static final String WALLPAPER_INFO_KEY = "/data/system/wallpaper_info.xml"; 48 49 // Stage file - should be adjacent to the WALLPAPER_IMAGE location. The wallpapers 50 // will be saved to this file from the restore stream, then renamed to the proper 51 // location if it's deemed suitable. 52 // TODO: Will need to change if backing up non-primary user's wallpaper 53 private static final String STAGE_FILE = "/data/system/users/0/wallpaper-tmp"; 54 55 Context mContext; 56 String[] mFiles; 57 String[] mKeys; 58 double mDesiredMinWidth; 59 double mDesiredMinHeight; 60 61 /** 62 * Construct a helper for backing up / restoring the files at the given absolute locations 63 * within the file system. 64 * 65 * @param context 66 * @param files 67 */ 68 public WallpaperBackupHelper(Context context, String[] files, String[] keys) { 69 super(context); 70 71 mContext = context; 72 mFiles = files; 73 mKeys = keys; 74 75 WallpaperManager wpm; 76 wpm = (WallpaperManager) context.getSystemService(Context.WALLPAPER_SERVICE); 77 mDesiredMinWidth = (double) wpm.getDesiredMinimumWidth(); 78 mDesiredMinHeight = (double) wpm.getDesiredMinimumHeight(); 79 80 if (mDesiredMinWidth <= 0 || mDesiredMinHeight <= 0) { 81 WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); 82 Display d = wm.getDefaultDisplay(); 83 Point size = new Point(); 84 d.getSize(size); 85 mDesiredMinWidth = size.x; 86 mDesiredMinHeight = size.y; 87 } 88 89 if (DEBUG) { 90 Slog.d(TAG, "dmW=" + mDesiredMinWidth + " dmH=" + mDesiredMinHeight); 91 } 92 } 93 94 /** 95 * Based on oldState, determine which of the files from the application's data directory 96 * need to be backed up, write them to the data stream, and fill in newState with the 97 * state as it exists now. 98 */ 99 public void performBackup(ParcelFileDescriptor oldState, BackupDataOutput data, 100 ParcelFileDescriptor newState) { 101 performBackup_checked(oldState, data, newState, mFiles, mKeys); 102 } 103 104 /** 105 * Restore one absolute file entity from the restore stream. If we're restoring the 106 * magic wallpaper file, take specific action to determine whether it is suitable for 107 * the current device. 108 */ 109 public void restoreEntity(BackupDataInputStream data) { 110 final String key = data.getKey(); 111 if (isKeyInList(key, mKeys)) { 112 if (key.equals(WALLPAPER_IMAGE_KEY)) { 113 // restore the file to the stage for inspection 114 File f = new File(STAGE_FILE); 115 if (writeFile(f, data)) { 116 117 // Preflight the restored image's dimensions without loading it 118 BitmapFactory.Options options = new BitmapFactory.Options(); 119 options.inJustDecodeBounds = true; 120 BitmapFactory.decodeFile(STAGE_FILE, options); 121 122 if (DEBUG) Slog.d(TAG, "Restoring wallpaper image w=" + options.outWidth 123 + " h=" + options.outHeight); 124 125 // How much does the image differ from our preference? The threshold 126 // here is set to accept any image larger than our target, because 127 // scaling down is acceptable; but to reject images that are deemed 128 // "too small" to scale up attractively. The value 1.33 is just barely 129 // too low to pass Nexus 1 or Droid wallpapers for use on a Xoom, but 130 // will pass anything relatively larger. 131 double widthRatio = mDesiredMinWidth / options.outWidth; 132 double heightRatio = mDesiredMinHeight / options.outHeight; 133 if (widthRatio > 0 && widthRatio < 1.33 134 && heightRatio > 0 && heightRatio < 1.33) { 135 // sufficiently close to our resolution; go ahead and use it 136 if (DEBUG) Slog.d(TAG, "wallpaper dimension match; using"); 137 f.renameTo(new File(WALLPAPER_IMAGE)); 138 // TODO: spin a service to copy the restored image to sd/usb storage, 139 // since it does not exist anywhere other than the private wallpaper 140 // file. 141 } else { 142 if (DEBUG) Slog.d(TAG, "dimensions too far off: wr=" + widthRatio 143 + " hr=" + heightRatio); 144 f.delete(); 145 } 146 } 147 } else if (key.equals(WALLPAPER_INFO_KEY)) { 148 // XML file containing wallpaper info 149 File f = new File(WALLPAPER_INFO); 150 writeFile(f, data); 151 } 152 } 153 } 154 } 155
