1 files changed, 115 insertions, 0 deletions
diff --git a/src/com/android/gallery3d/data/FilterDeleteSet.java b/src/com/android/gallery3d/data/FilterDeleteSet.java
new file mode 100644
index 000000000..fc94eb8e0
--- /dev/null
+++ b/src/com/android/gallery3d/data/FilterDeleteSet.java
@@ -0,0 +1,115 @@
+/*
+ * 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 a deletion item. The user
+// can use the following method to change the deletion item:
+//
+// void setDeletion(Path path, int index);
+//
+// If the path is null, there is no deletion item.
+public class FilterDeleteSet extends MediaSet implements ContentListener {
+    private static final String TAG = "FilterDeleteSet";
+
+    private final MediaSet mBaseSet;
+    private Path mDeletionPath;
+    private int mDeletionIndexHint;
+    private boolean mNewDeletionSettingPending = false;
+
+    // This is set to true or false in reload(), so we know if the given
+    // mDelectionPath is still in the mBaseSet, and if so we can adjust the
+    // index and items.
+    private boolean mDeletionInEffect;
+    private int mDeletionIndex;
+
+    public FilterDeleteSet(Path path, MediaSet baseSet) {
+        super(path, INVALID_DATA_VERSION);
+        mBaseSet = baseSet;
+        mBaseSet.addContentListener(this);
+    }
+
+    @Override
+    public String getName() {
+        return mBaseSet.getName();
+    }
+
+    @Override
+    public int getMediaItemCount() {
+        if (mDeletionInEffect) {
+            return mBaseSet.getMediaItemCount() - 1;
+        } else {
+            return mBaseSet.getMediaItemCount();
+        }
+    }
+
+    @Override
+    public ArrayList<MediaItem> getMediaItem(int start, int count) {
+        if (!mDeletionInEffect || mDeletionIndex >= start + count) {
+            return mBaseSet.getMediaItem(start, count);
+        }
+        if (mDeletionIndex < start) {
+            return mBaseSet.getMediaItem(start + 1, count);
+        }
+        ArrayList<MediaItem> base = mBaseSet.getMediaItem(start, count + 1);
+        base.remove(mDeletionIndex - start);
+        return base;
+    }
+
+    @Override
+    public long reload() {
+        boolean newData = mBaseSet.reload() > mDataVersion;
+        if (!newData && !mNewDeletionSettingPending) return mDataVersion;
+        mNewDeletionSettingPending = false;
+        mDeletionInEffect = false;
+        if (mDeletionPath != null) {
+            // See if mDeletionPath can be found in the MediaSet. We don't want
+            // to search the whole mBaseSet, so we just search a small window
+            // that is close the the index hint.
+            int n = mBaseSet.getMediaItemCount();
+            int from = Math.max(mDeletionIndexHint - 5, 0);
+            int to = Math.min(mDeletionIndexHint + 5, n);
+            ArrayList<MediaItem> items = mBaseSet.getMediaItem(from, to - from);
+            for (int i = 0; i < items.size(); i++) {
+                MediaItem item = items.get(i);
+                if (item != null && item.getPath() == mDeletionPath) {
+                    mDeletionInEffect = true;
+                    mDeletionIndex = i + from;
+                }
+            }
+            // We cannot find this path. Set it to null to avoid further search.
+            if (!mDeletionInEffect) {
+                mDeletionPath = null;
+            }
+        }
+        mDataVersion = nextVersionNumber();
+        return mDataVersion;
+    }
+
+    @Override
+    public void onContentDirty() {
+        notifyContentChanged();
+    }
+
+    public void setDeletion(Path path, int indexHint) {
+        mDeletionPath = path;
+        mDeletionIndexHint = indexHint;
+        mNewDeletionSettingPending = true;
+        notifyContentChanged();
+    }
+}