| /* |
| * Copyright (C) 2010 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.app.backup; |
| |
| import android.app.WallpaperManager; |
| import android.content.Context; |
| import android.graphics.BitmapFactory; |
| import android.os.ParcelFileDescriptor; |
| import android.util.Slog; |
| |
| import java.io.File; |
| |
| /** |
| * Helper for backing up / restoring wallpapers. Basically an AbsoluteFileBackupHelper, |
| * but with logic for deciding what to do with restored wallpaper images. |
| * |
| * @hide |
| */ |
| public class WallpaperBackupHelper extends FileBackupHelperBase implements BackupHelper { |
| private static final String TAG = "WallpaperBackupHelper"; |
| private static final boolean DEBUG = false; |
| |
| // This path must match what the WallpaperManagerService uses |
| private static final String WALLPAPER_IMAGE = "/data/data/com.android.settings/files/wallpaper"; |
| |
| // Stage file - should be adjacent to the WALLPAPER_IMAGE location. The wallpapers |
| // will be saved to this file from the restore stream, then renamed to the proper |
| // location if it's deemed suitable. |
| private static final String STAGE_FILE = "/data/data/com.android.settings/files/wallpaper-tmp"; |
| |
| Context mContext; |
| String[] mFiles; |
| double mDesiredMinWidth; |
| double mDesiredMinHeight; |
| |
| /** |
| * Construct a helper for backing up / restoring the files at the given absolute locations |
| * within the file system. |
| * |
| * @param context |
| * @param files |
| */ |
| public WallpaperBackupHelper(Context context, String... files) { |
| super(context); |
| |
| mContext = context; |
| mFiles = files; |
| |
| WallpaperManager wpm; |
| wpm = (WallpaperManager) context.getSystemService(Context.WALLPAPER_SERVICE); |
| mDesiredMinWidth = (double) wpm.getDesiredMinimumWidth(); |
| mDesiredMinHeight = (double) wpm.getDesiredMinimumHeight(); |
| } |
| |
| /** |
| * Based on oldState, determine which of the files from the application's data directory |
| * need to be backed up, write them to the data stream, and fill in newState with the |
| * state as it exists now. |
| */ |
| public void performBackup(ParcelFileDescriptor oldState, BackupDataOutput data, |
| ParcelFileDescriptor newState) { |
| performBackup_checked(oldState, data, newState, mFiles, mFiles); |
| } |
| |
| /** |
| * Restore one absolute file entity from the restore stream. If we're restoring the |
| * magic wallpaper file, take specific action to determine whether it is suitable for |
| * the current device. |
| */ |
| public void restoreEntity(BackupDataInputStream data) { |
| final String key = data.getKey(); |
| if (isKeyInList(key, mFiles)) { |
| if (key.equals(WALLPAPER_IMAGE)) { |
| // restore the file to the stage for inspection |
| File f = new File(STAGE_FILE); |
| if (writeFile(f, data)) { |
| |
| // Preflight the restored image's dimensions without loading it |
| BitmapFactory.Options options = new BitmapFactory.Options(); |
| options.inJustDecodeBounds = true; |
| BitmapFactory.decodeFile(STAGE_FILE, options); |
| |
| if (DEBUG) Slog.v(TAG, "Restoring wallpaper image w=" + options.outWidth |
| + " h=" + options.outHeight); |
| |
| // how much does the image differ from our preference? |
| double widthRatio = mDesiredMinWidth / options.outWidth; |
| double heightRatio = mDesiredMinHeight / options.outHeight; |
| if (widthRatio > 0.8 && widthRatio < 1.25 |
| && heightRatio > 0.8 && heightRatio < 1.25) { |
| // sufficiently close to our resolution; go ahead and use it |
| if (DEBUG) Slog.v(TAG, "wallpaper dimension match; using"); |
| f.renameTo(new File(WALLPAPER_IMAGE)); |
| // TODO: spin a service to copy the restored image to sd/usb storage, |
| // since it does not exist anywhere other than the private wallpaper |
| // file. |
| } else { |
| if (DEBUG) Slog.v(TAG, "dimensions too far off: wr=" + widthRatio |
| + " hr=" + heightRatio); |
| f.delete(); |
| } |
| } |
| } else { |
| // Some other normal file; just decode it to its destination |
| File f = new File(key); |
| writeFile(f, data); |
| } |
| } |
| } |
| } |