/*
* 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.pinnedlist;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import java.util.Collection;
/**
* A general purpose adapter that is composed of multiple Collections. It just
* appends them in the order they are added.
*/
/**
* This class is used instead of {@link CompositeAdapter} because creating
* a cursor with the needed data would be too much in this case, using the POJOS
* from start to end is an easier choice
*/
public abstract class CompositeAdapter extends BaseAdapter {
private static final int INITIAL_CAPACITY = 2;
public static class Partition {
boolean showIfEmpty;
int header = -1;
Collection<?> elements;
int count;
public Partition(boolean showIfEmpty, int header) {
this.showIfEmpty = showIfEmpty;
this.header = header;
}
public boolean hasHeader() {
return header != -1;
}
public int getHeader() {
return header;
}
public void setElements(Collection<?> elements) {
this.elements = elements;
}
}
private final Context mContext;
private Partition[] mPartitions;
private int mSize = 0;
private int mCount = 0;
private boolean mCacheValid = true;
private boolean mNotificationsEnabled = true;
public CompositeAdapter(Context context) {
this(context, INITIAL_CAPACITY);
}
public CompositeAdapter(Context context, int initialCapacity) {
mContext = context;
mPartitions = new Partition[initialCapacity];
}
public Context getContext() {
return mContext;
}
public void setPartitions(Partition... partitions) {
mPartitions = partitions;
mSize = mPartitions.length;
invalidate();
notifyDataSetChanged();
}
/**
* Removes all partitions.
*/
public void close() {
mSize = 0;
invalidate();
notifyDataSetChanged();
}
public Partition getPartition(int partitionIndex) {
if (partitionIndex >= mSize) {
throw new ArrayIndexOutOfBoundsException(partitionIndex);
}
return mPartitions[partitionIndex];
}
protected void invalidate() {
mCacheValid = false;
}
public int getPartitionCount() {
return mSize;
}
protected void ensureCacheValid() {
if (mCacheValid) {
return;
}
mCount = 0;
for (int i = 0; i < mSize; i++) {
Collection<?> elements = mPartitions[i].elements;
int count = elements != null ? elements.size() : 0;
if (mPartitions[i].hasHeader()) {
if (count != 0 || mPartitions[i].showIfEmpty) {
count++;
}
}
mPartitions[i].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[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 Collection<?> getElements(int partition) {
return mPartitions[partition].elements;
}
/**
* Returns true if the specified partition has no cursor or an empty cursor.
*/
public boolean isPartitionEmpty(int partition) {
Collection<?> elements = mPartitions[partition].elements;
return elements == null || elements.size() == 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; i < mSize; i++) {
int end = start + mPartitions[i].count;
if (position >= start && position < end) {
return i;
}
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[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; i < mSize; i++) {
int end = start + mPartitions[i].count;
if (position >= start && position < end) {
int offset = position - start;
if (mPartitions[i].hasHeader() && offset == 0) {
return IGNORE_ITEM_VIEW_TYPE;
}
return getItemViewType(i, position);
}
start = end;
}
throw new ArrayIndexOutOfBoundsException(position);
}
public View getView(int position, View convertView, ViewGroup parent) {
ensureCacheValid();
int start = 0;
for (int i = 0; i < mSize; i++) {
int end = start + mPartitions[i].count;
if (position >= start && position < end) {
int offset = position - start;
if (mPartitions[i].hasHeader()) {
offset--;
}
View view;
if (offset == -1) {
view = getHeaderView(i, mPartitions[i].elements, convertView, parent);
}
else {
if (mPartitions[i].elements.size() < offset) {
throw new IllegalStateException("Cannot access element : " + offset);
}
view = getView(i, mPartitions[i].elements.toArray()[offset], 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, Collection<?> elements, View convertView, ViewGroup parent) {
View view = convertView != null ? convertView : newHeaderView(mContext, partition, elements, parent);
bindHeaderView(view, partition, elements);
return view;
}
/**
* Creates the header view for the specified partition.
*/
protected abstract View newHeaderView(Context context, int partition, Collection<?> elements, ViewGroup parent);
/**
* Binds the header view for the specified partition.
*/
protected abstract void bindHeaderView(View view, int partition, Collection<?> elements);
/**
* Returns an item view for the specified partition, creating one if needed.
*/
protected View getView(int partition, Object element, int position, View convertView, ViewGroup parent) {
View view;
if (convertView != null) {
view = convertView;
}
else {
view = newView(mContext, partition, element, position, parent);
}
bindView(view, partition, element, 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, Object element, 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, Object element, int position);
/**
* Returns the elements linked to the position.
*/
public Object getItem(int position) {
ensureCacheValid();
int start = 0;
for (int i = 0; i < mSize; i++) {
int end = start + mPartitions[i].count;
if (position >= start && position < end) {
int offset = position - start;
if (mPartitions[i].hasHeader()) {
offset--;
}
if (offset == -1) {
return null;
}
return mPartitions[i].elements;
}
start = end;
}
return null;
}
/**
* Returns the item ID for the specified list position.
*/
public long getItemId(int position) {
return position;
}
/**
* Returns false if any partition has a header.
*/
@Override
public boolean areAllItemsEnabled() {
for (int i = 0; i < mSize; i++) {
if (mPartitions[i].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; i < mSize; i++) {
int end = start + mPartitions[i].count;
if (position >= start && position < end) {
int offset = position - start;
if (mPartitions[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;
}
public void setNotificationsEnabled(boolean notificationsEnabled) {
this.mNotificationsEnabled = notificationsEnabled;
}
@Override
public void notifyDataSetChanged() {
if (mNotificationsEnabled) {
super.notifyDataSetChanged();
}
}
}