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Diffstat (limited to 'src/com/android/launcher3/list/CompositeCursorAdapter.java')
| -rw-r--r-- | src/com/android/launcher3/list/CompositeCursorAdapter.java | 532 |
1 files changed, 532 insertions, 0 deletions
diff --git a/src/com/android/launcher3/list/CompositeCursorAdapter.java b/src/com/android/launcher3/list/CompositeCursorAdapter.java new file mode 100644 index 000000000..b163c501c --- /dev/null +++ b/src/com/android/launcher3/list/CompositeCursorAdapter.java @@ -0,0 +1,532 @@ +/* + * 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 com.android.launcher3.list; + +import android.content.Context; +import android.database.Cursor; +import android.view.View; +import android.view.ViewGroup; +import android.widget.BaseAdapter; + +import java.util.ArrayList; + +/** + * A general purpose adapter that is composed of multiple cursors. It just + * appends them in the order they are added. + */ +public abstract class CompositeCursorAdapter extends BaseAdapter { + + private static final int INITIAL_CAPACITY = 2; + + public static class Partition { + boolean showIfEmpty; + boolean hasHeader; + + Cursor cursor; + int idColumnIndex; + int count; + + public Partition(boolean showIfEmpty, boolean hasHeader) { + this.showIfEmpty = showIfEmpty; + this.hasHeader = hasHeader; + } + + /** + * True if the directory should be shown even if no contacts are found. + */ + public boolean getShowIfEmpty() { + return showIfEmpty; + } + + public boolean getHasHeader() { + return hasHeader; + } + } + + private final Context mContext; + private ArrayList<Partition> mPartitions; + private int mCount = 0; + private boolean mCacheValid = true; + private boolean mNotificationsEnabled = true; + private boolean mNotificationNeeded; + + public CompositeCursorAdapter(Context context) { + this(context, INITIAL_CAPACITY); + } + + public CompositeCursorAdapter(Context context, int initialCapacity) { + mContext = context; + mPartitions = new ArrayList<Partition>(); + } + + public Context getContext() { + return mContext; + } + + /** + * Registers a partition. The cursor for that partition can be set later. + * Partitions should be added in the order they are supposed to appear in the + * list. + */ + public void addPartition(boolean showIfEmpty, boolean hasHeader) { + addPartition(new Partition(showIfEmpty, hasHeader)); + } + + public void addPartition(Partition partition) { + mPartitions.add(partition); + invalidate(); + notifyDataSetChanged(); + } + + public void addPartition(int location, Partition partition) { + mPartitions.add(location, partition); + invalidate(); + notifyDataSetChanged(); + } + + public void removePartition(int partitionIndex) { + Cursor cursor = mPartitions.get(partitionIndex).cursor; + if (cursor != null && !cursor.isClosed()) { + cursor.close(); + } + mPartitions.remove(partitionIndex); + invalidate(); + notifyDataSetChanged(); + } + + /** + * Removes cursors for all partitions. + */ + // TODO: Is this really what this is supposed to do? Just remove the cursors? Not close them? + // Not remove the partitions themselves? Isn't this leaking? + + public void clearPartitions() { + for (Partition partition : mPartitions) { + partition.cursor = null; + } + invalidate(); + notifyDataSetChanged(); + } + + /** + * Closes all cursors and removes all partitions. + */ + public void close() { + for (Partition partition : mPartitions) { + Cursor cursor = partition.cursor; + if (cursor != null && !cursor.isClosed()) { + cursor.close(); + } + } + mPartitions.clear(); + invalidate(); + notifyDataSetChanged(); + } + + public void setHasHeader(int partitionIndex, boolean flag) { + mPartitions.get(partitionIndex).hasHeader = flag; + invalidate(); + } + + public void setShowIfEmpty(int partitionIndex, boolean flag) { + mPartitions.get(partitionIndex).showIfEmpty = flag; + invalidate(); + } + + public Partition getPartition(int partitionIndex) { + return mPartitions.get(partitionIndex); + } + + protected void invalidate() { + mCacheValid = false; + } + + public int getPartitionCount() { + return mPartitions.size(); + } + + protected void ensureCacheValid() { + if (mCacheValid) { + return; + } + + mCount = 0; + for (Partition partition : mPartitions) { + Cursor cursor = partition.cursor; + int count = cursor != null ? cursor.getCount() : 0; + if (partition.hasHeader) { + if (count != 0 || partition.showIfEmpty) { + count++; + } + } + partition.count = count; + mCount += count; + } + + mCacheValid = true; + } + + /** + * Returns true if the specified partition was configured to have a header. + */ + public boolean hasHeader(int partition) { + return mPartitions.get(partition).hasHeader; + } + + /** + * Returns the total number of list items in all partitions. + */ + public int getCount() { + ensureCacheValid(); + return mCount; + } + + /** + * Returns the cursor for the given partition + */ + public Cursor getCursor(int partition) { + return mPartitions.get(partition).cursor; + } + + /** + * Changes the cursor for an individual partition. + */ + public void changeCursor(int partition, Cursor cursor) { + Cursor prevCursor = mPartitions.get(partition).cursor; + if (prevCursor != cursor) { + if (prevCursor != null && !prevCursor.isClosed()) { + prevCursor.close(); + } + mPartitions.get(partition).cursor = cursor; + if (cursor != null) { + mPartitions.get(partition).idColumnIndex = cursor.getColumnIndex("_id"); + } + invalidate(); + notifyDataSetChanged(); + } + } + + /** + * Returns true if the specified partition has no cursor or an empty cursor. + */ + public boolean isPartitionEmpty(int partition) { + Cursor cursor = mPartitions.get(partition).cursor; + return cursor == null || cursor.getCount() == 0; + } + + /** + * Given a list position, returns the index of the corresponding partition. + */ + public int getPartitionForPosition(int position) { + ensureCacheValid(); + int start = 0; + for (int i = 0, n = mPartitions.size(); i < n; i++) { + int end = start + mPartitions.get(i).count; + if (position >= start && position < end) { + return i; + } + start = end; + } + return -1; + } + + /** + * Given a list position, return the offset of the corresponding item in its + * partition. The header, if any, will have offset -1. + */ + public int getOffsetInPartition(int position) { + ensureCacheValid(); + int start = 0; + for (Partition partition : mPartitions) { + int end = start + partition.count; + if (position >= start && position < end) { + int offset = position - start; + if (partition.hasHeader) { + offset--; + } + return offset; + } + start = end; + } + return -1; + } + + /** + * Returns the first list position for the specified partition. + */ + public int getPositionForPartition(int partition) { + ensureCacheValid(); + int position = 0; + for (int i = 0; i < partition; i++) { + position += mPartitions.get(i).count; + } + return position; + } + + @Override + public int getViewTypeCount() { + return getItemViewTypeCount() + 1; + } + + /** + * Returns the overall number of item view types across all partitions. An + * implementation of this method needs to ensure that the returned count is + * consistent with the values returned by {@link #getItemViewType(int,int)}. + */ + public int getItemViewTypeCount() { + return 1; + } + + /** + * Returns the view type for the list item at the specified position in the + * specified partition. + */ + protected int getItemViewType(int partition, int position) { + return 1; + } + + @Override + public int getItemViewType(int position) { + ensureCacheValid(); + int start = 0; + for (int i = 0, n = mPartitions.size(); i < n; i++) { + int end = start + mPartitions.get(i).count; + if (position >= start && position < end) { + int offset = position - start; + if (mPartitions.get(i).hasHeader) { + offset--; + } + if (offset == -1) { + return IGNORE_ITEM_VIEW_TYPE; + } else { + return getItemViewType(i, offset); + } + } + start = end; + } + + throw new ArrayIndexOutOfBoundsException(position); + } + + public View getView(int position, View convertView, ViewGroup parent) { + ensureCacheValid(); + int start = 0; + for (int i = 0, n = mPartitions.size(); i < n; i++) { + int end = start + mPartitions.get(i).count; + if (position >= start && position < end) { + int offset = position - start; + if (mPartitions.get(i).hasHeader) { + offset--; + } + View view; + if (offset == -1) { + view = getHeaderView(i, mPartitions.get(i).cursor, convertView, parent); + } else { + if (!mPartitions.get(i).cursor.moveToPosition(offset)) { + throw new IllegalStateException("Couldn't move cursor to position " + + offset); + } + view = getView(i, mPartitions.get(i).cursor, offset, convertView, parent); + } + if (view == null) { + throw new NullPointerException("View should not be null, partition: " + i + + " position: " + offset); + } + return view; + } + start = end; + } + + throw new ArrayIndexOutOfBoundsException(position); + } + + /** + * Returns the header view for the specified partition, creating one if needed. + */ + protected View getHeaderView(int partition, Cursor cursor, View convertView, + ViewGroup parent) { + View view = convertView != null + ? convertView + : newHeaderView(mContext, partition, cursor, parent); + bindHeaderView(view, partition, cursor); + return view; + } + + /** + * Creates the header view for the specified partition. + */ + protected View newHeaderView(Context context, int partition, Cursor cursor, + ViewGroup parent) { + return null; + } + + /** + * Binds the header view for the specified partition. + */ + protected void bindHeaderView(View view, int partition, Cursor cursor) { + } + + /** + * Returns an item view for the specified partition, creating one if needed. + */ + protected View getView(int partition, Cursor cursor, int position, View convertView, + ViewGroup parent) { + View view; + if (convertView != null) { + view = convertView; + } else { + view = newView(mContext, partition, cursor, position, parent); + } + bindView(view, partition, cursor, position); + return view; + } + + /** + * Creates an item view for the specified partition and position. Position + * corresponds directly to the current cursor position. + */ + protected abstract View newView(Context context, int partition, Cursor cursor, int position, + ViewGroup parent); + + /** + * Binds an item view for the specified partition and position. Position + * corresponds directly to the current cursor position. + */ + protected abstract void bindView(View v, int partition, Cursor cursor, int position); + + /** + * Returns a pre-positioned cursor for the specified list position. + */ + public Object getItem(int position) { + ensureCacheValid(); + int start = 0; + for (Partition mPartition : mPartitions) { + int end = start + mPartition.count; + if (position >= start && position < end) { + int offset = position - start; + if (mPartition.hasHeader) { + offset--; + } + if (offset == -1) { + return null; + } + Cursor cursor = mPartition.cursor; + cursor.moveToPosition(offset); + return cursor; + } + start = end; + } + + return null; + } + + /** + * Returns the item ID for the specified list position. + */ + public long getItemId(int position) { + ensureCacheValid(); + int start = 0; + for (Partition mPartition : mPartitions) { + int end = start + mPartition.count; + if (position >= start && position < end) { + int offset = position - start; + if (mPartition.hasHeader) { + offset--; + } + if (offset == -1) { + return 0; + } + if (mPartition.idColumnIndex == -1) { + return 0; + } + + Cursor cursor = mPartition.cursor; + if (cursor == null || cursor.isClosed() || !cursor.moveToPosition(offset)) { + return 0; + } + return cursor.getLong(mPartition.idColumnIndex); + } + start = end; + } + + return 0; + } + + /** + * Returns false if any partition has a header. + */ + @Override + public boolean areAllItemsEnabled() { + for (Partition mPartition : mPartitions) { + if (mPartition.hasHeader) { + return false; + } + } + return true; + } + + /** + * Returns true for all items except headers. + */ + @Override + public boolean isEnabled(int position) { + ensureCacheValid(); + int start = 0; + for (int i = 0, n = mPartitions.size(); i < n; i++) { + int end = start + mPartitions.get(i).count; + if (position >= start && position < end) { + int offset = position - start; + if (mPartitions.get(i).hasHeader && offset == 0) { + return false; + } else { + return isEnabled(i, offset); + } + } + start = end; + } + + return false; + } + + /** + * Returns true if the item at the specified offset of the specified + * partition is selectable and clickable. + */ + protected boolean isEnabled(int partition, int position) { + return true; + } + + /** + * Enable or disable data change notifications. It may be a good idea to + * disable notifications before making changes to several partitions at once. + */ + public void setNotificationsEnabled(boolean flag) { + mNotificationsEnabled = flag; + if (flag && mNotificationNeeded) { + notifyDataSetChanged(); + } + } + + @Override + public void notifyDataSetChanged() { + if (mNotificationsEnabled) { + mNotificationNeeded = false; + super.notifyDataSetChanged(); + } else { + mNotificationNeeded = true; + } + } +}
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