diff options
Diffstat (limited to 'src/com/android/gallery3d/data/FilterDeleteSet.java')
-rw-r--r-- | src/com/android/gallery3d/data/FilterDeleteSet.java | 256 |
1 files changed, 0 insertions, 256 deletions
diff --git a/src/com/android/gallery3d/data/FilterDeleteSet.java b/src/com/android/gallery3d/data/FilterDeleteSet.java deleted file mode 100644 index c76412ff8..000000000 --- a/src/com/android/gallery3d/data/FilterDeleteSet.java +++ /dev/null @@ -1,256 +0,0 @@ -/* - * Copyright (C) 2012 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.gallery3d.data; - -import java.util.ArrayList; - -// FilterDeleteSet filters a base MediaSet to remove some deletion items (we -// expect the number to be small). The user can use the following methods to -// add/remove deletion items: -// -// void addDeletion(Path path, int index); -// void removeDelection(Path path); -// void clearDeletion(); -// int getNumberOfDeletions(); -// -public class FilterDeleteSet extends MediaSet implements ContentListener { - @SuppressWarnings("unused") - private static final String TAG = "FilterDeleteSet"; - - private static final int REQUEST_ADD = 1; - private static final int REQUEST_REMOVE = 2; - private static final int REQUEST_CLEAR = 3; - - private static class Request { - int type; // one of the REQUEST_* constants - Path path; - int indexHint; - public Request(int type, Path path, int indexHint) { - this.type = type; - this.path = path; - this.indexHint = indexHint; - } - } - - private static class Deletion { - Path path; - int index; - public Deletion(Path path, int index) { - this.path = path; - this.index = index; - } - } - - // The underlying MediaSet - private final MediaSet mBaseSet; - - // Pending Requests - private ArrayList<Request> mRequests = new ArrayList<Request>(); - - // Deletions currently in effect, ordered by index - private ArrayList<Deletion> mCurrent = new ArrayList<Deletion>(); - - public FilterDeleteSet(Path path, MediaSet baseSet) { - super(path, INVALID_DATA_VERSION); - mBaseSet = baseSet; - mBaseSet.addContentListener(this); - } - - @Override - public boolean isCameraRoll() { - return mBaseSet.isCameraRoll(); - } - - @Override - public String getName() { - return mBaseSet.getName(); - } - - @Override - public int getMediaItemCount() { - return mBaseSet.getMediaItemCount() - mCurrent.size(); - } - - // Gets the MediaItems whose (post-deletion) index are in the range [start, - // start + count). Because we remove some of the MediaItems, the index need - // to be adjusted. - // - // For example, if there are 12 items in total. The deleted items are 3, 5, - // 10, and the the requested range is [3, 7]: - // - // The original index: 0 1 2 3 4 5 6 7 8 9 A B C - // The deleted items: X X X - // The new index: 0 1 2 3 4 5 6 7 8 9 - // Requested: * * * * * - // - // We need to figure out the [3, 7] actually maps to the original index 4, - // 6, 7, 8, 9. - // - // We can break the MediaItems into segments, each segment other than the - // last one ends in a deleted item. The difference between the new index and - // the original index increases with each segment: - // - // 0 1 2 X (new index = old index) - // 4 X (new index = old index - 1) - // 6 7 8 9 X (new index = old index - 2) - // B C (new index = old index - 3) - // - @Override - public ArrayList<MediaItem> getMediaItem(int start, int count) { - if (count <= 0) return new ArrayList<MediaItem>(); - - int end = start + count - 1; - int n = mCurrent.size(); - // Find the segment that "start" falls into. Count the number of items - // not yet deleted until it reaches "start". - int i = 0; - for (i = 0; i < n; i++) { - Deletion d = mCurrent.get(i); - if (d.index - i > start) break; - } - // Find the segment that "end" falls into. - int j = i; - for (; j < n; j++) { - Deletion d = mCurrent.get(j); - if (d.index - j > end) break; - } - - // Now get enough to cover deleted items in [start, end] - ArrayList<MediaItem> base = mBaseSet.getMediaItem(start + i, count + (j - i)); - - // Remove the deleted items. - for (int m = j - 1; m >= i; m--) { - Deletion d = mCurrent.get(m); - int k = d.index - (start + i); - base.remove(k); - } - return base; - } - - // We apply the pending requests in the mRequests to construct mCurrent in reload(). - @Override - public long reload() { - boolean newData = mBaseSet.reload() > mDataVersion; - synchronized (mRequests) { - if (!newData && mRequests.isEmpty()) { - return mDataVersion; - } - for (int i = 0; i < mRequests.size(); i++) { - Request r = mRequests.get(i); - switch (r.type) { - case REQUEST_ADD: { - // Add the path into mCurrent if there is no duplicate. - int n = mCurrent.size(); - int j; - for (j = 0; j < n; j++) { - if (mCurrent.get(j).path == r.path) break; - } - if (j == n) { - mCurrent.add(new Deletion(r.path, r.indexHint)); - } - break; - } - case REQUEST_REMOVE: { - // Remove the path from mCurrent. - int n = mCurrent.size(); - for (int j = 0; j < n; j++) { - if (mCurrent.get(j).path == r.path) { - mCurrent.remove(j); - break; - } - } - break; - } - case REQUEST_CLEAR: { - mCurrent.clear(); - break; - } - } - } - mRequests.clear(); - } - - if (!mCurrent.isEmpty()) { - // See if the elements in mCurrent can be found in the MediaSet. We - // don't want to search the whole mBaseSet, so we just search a - // small window that contains the index hints (plus some margin). - int minIndex = mCurrent.get(0).index; - int maxIndex = minIndex; - for (int i = 1; i < mCurrent.size(); i++) { - Deletion d = mCurrent.get(i); - minIndex = Math.min(d.index, minIndex); - maxIndex = Math.max(d.index, maxIndex); - } - - int n = mBaseSet.getMediaItemCount(); - int from = Math.max(minIndex - 5, 0); - int to = Math.min(maxIndex + 5, n); - ArrayList<MediaItem> items = mBaseSet.getMediaItem(from, to - from); - ArrayList<Deletion> result = new ArrayList<Deletion>(); - for (int i = 0; i < items.size(); i++) { - MediaItem item = items.get(i); - if (item == null) continue; - Path p = item.getPath(); - // Find the matching path in mCurrent, if found move it to result - for (int j = 0; j < mCurrent.size(); j++) { - Deletion d = mCurrent.get(j); - if (d.path == p) { - d.index = from + i; - result.add(d); - mCurrent.remove(j); - break; - } - } - } - mCurrent = result; - } - - mDataVersion = nextVersionNumber(); - return mDataVersion; - } - - private void sendRequest(int type, Path path, int indexHint) { - Request r = new Request(type, path, indexHint); - synchronized (mRequests) { - mRequests.add(r); - } - notifyContentChanged(); - } - - @Override - public void onContentDirty() { - notifyContentChanged(); - } - - public void addDeletion(Path path, int indexHint) { - sendRequest(REQUEST_ADD, path, indexHint); - } - - public void removeDeletion(Path path) { - sendRequest(REQUEST_REMOVE, path, 0 /* unused */); - } - - public void clearDeletion() { - sendRequest(REQUEST_CLEAR, null /* unused */ , 0 /* unused */); - } - - // Returns number of deletions _in effect_ (the number will only gets - // updated after a reload()). - public int getNumberOfDeletions() { - return mCurrent.size(); - } -} |