/*
* 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.contacts.widget;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.SectionIndexer;
/**
* A list adapter that supports section indexer and a pinned header.
*/
public abstract class IndexerListAdapter extends PinnedHeaderListAdapter implements SectionIndexer {
protected Context mContext;
private SectionIndexer mIndexer;
private int mIndexedPartition = 0;
private boolean mSectionHeaderDisplayEnabled;
private View mHeader;
/**
* An item view is displayed differently depending on whether it is placed
* at the beginning, middle or end of a section. It also needs to know the
* section header when it is at the beginning of a section. This object
* captures all this configuration.
*/
public static final class Placement {
private int position = ListView.INVALID_POSITION;
public boolean firstInSection;
public boolean lastInSection;
public String sectionHeader;
public void invalidate() {
position = ListView.INVALID_POSITION;
}
}
private Placement mPlacementCache = new Placement();
/**
* Constructor.
*/
public IndexerListAdapter(Context context) {
super(context);
mContext = context;
}
/**
* Creates a section header view that will be pinned at the top of the list
* as the user scrolls.
*/
protected abstract View createPinnedSectionHeaderView(Context context, ViewGroup parent);
/**
* Sets the title in the pinned header as the user scrolls.
*/
protected abstract void setPinnedSectionTitle(View pinnedHeaderView, String title);
/**
* Sets the contacts count in the pinned header.
*/
protected abstract void setPinnedHeaderContactsCount(View header);
/**
* clears the contacts count in the pinned header and makes the view invisible.
*/
protected abstract void clearPinnedHeaderContactsCount(View header);
public boolean isSectionHeaderDisplayEnabled() {
return mSectionHeaderDisplayEnabled;
}
public void setSectionHeaderDisplayEnabled(boolean flag) {
this.mSectionHeaderDisplayEnabled = flag;
}
public int getIndexedPartition() {
return mIndexedPartition;
}
public void setIndexedPartition(int partition) {
this.mIndexedPartition = partition;
}
public SectionIndexer getIndexer() {
return mIndexer;
}
public void setIndexer(SectionIndexer indexer) {
mIndexer = indexer;
mPlacementCache.invalidate();
}
public Object[] getSections() {
if (mIndexer == null) {
return new String[] { " " };
} else {
return mIndexer.getSections();
}
}
/**
* @return relative position of the section in the indexed partition
*/
public int getPositionForSection(int sectionIndex) {
if (mIndexer == null) {
return -1;
}
return mIndexer.getPositionForSection(sectionIndex);
}
/**
* @param position relative position in the indexed partition
*/
public int getSectionForPosition(int position) {
if (mIndexer == null) {
return -1;
}
return mIndexer.getSectionForPosition(position);
}
@Override
public int getPinnedHeaderCount() {
if (isSectionHeaderDisplayEnabled()) {
return super.getPinnedHeaderCount() + 1;
} else {
return super.getPinnedHeaderCount();
}
}
@Override
public View getPinnedHeaderView(int viewIndex, View convertView, ViewGroup parent) {
if (isSectionHeaderDisplayEnabled() && viewIndex == getPinnedHeaderCount() - 1) {
if (mHeader == null) {
mHeader = createPinnedSectionHeaderView(mContext, parent);
}
return mHeader;
} else {
return super.getPinnedHeaderView(viewIndex, convertView, parent);
}
}
@Override
public void configurePinnedHeaders(PinnedHeaderListView listView) {
super.configurePinnedHeaders(listView);
if (!isSectionHeaderDisplayEnabled()) {
return;
}
int index = getPinnedHeaderCount() - 1;
if (mIndexer == null || getCount() == 0) {
listView.setHeaderInvisible(index, false);
} else {
int listPosition = listView.getPositionAt(listView.getTotalTopPinnedHeaderHeight());
int position = listPosition - listView.getHeaderViewsCount();
int section = -1;
int partition = getPartitionForPosition(position);
if (partition == mIndexedPartition) {
int offset = getOffsetInPartition(position);
if (offset != -1) {
section = getSectionForPosition(offset);
}
}
if (section == -1) {
listView.setHeaderInvisible(index, false);
} else {
setPinnedSectionTitle(mHeader, (String)mIndexer.getSections()[section]);
if (section == 0) {
setPinnedHeaderContactsCount(mHeader);
} else {
clearPinnedHeaderContactsCount(mHeader);
}
// Compute the item position where the current partition begins
int partitionStart = getPositionForPartition(mIndexedPartition);
if (hasHeader(mIndexedPartition)) {
partitionStart++;
}
// Compute the item position where the next section begins
int nextSectionPosition = partitionStart + getPositionForSection(section + 1);
boolean isLastInSection = position == nextSectionPosition - 1;
listView.setFadingHeader(index, listPosition, isLastInSection);
}
}
}
/**
* Computes the item's placement within its section and populates the {@code placement}
* object accordingly. Please note that the returned object is volatile and should be
* copied if the result needs to be used later.
*/
public Placement getItemPlacementInSection(int position) {
if (mPlacementCache.position == position) {
return mPlacementCache;
}
mPlacementCache.position = position;
if (isSectionHeaderDisplayEnabled()) {
int section = getSectionForPosition(position);
if (section != -1 && getPositionForSection(section) == position) {
mPlacementCache.firstInSection = true;
mPlacementCache.sectionHeader = (String)getSections()[section];
} else {
mPlacementCache.firstInSection = false;
mPlacementCache.sectionHeader = null;
}
mPlacementCache.lastInSection = (getPositionForSection(section + 1) - 1 == position);
} else {
mPlacementCache.firstInSection = false;
mPlacementCache.lastInSection = false;
mPlacementCache.sectionHeader = null;
}
return mPlacementCache;
}
}