Java tutorial
/** * Copyright (C) 2011 Whisper Systems * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.thoughtcrime.securesms; import android.content.Context; import android.database.Cursor; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.AbsListView; import android.support.v4.widget.CursorAdapter; import org.thoughtcrime.securesms.crypto.MasterSecret; import org.thoughtcrime.securesms.database.DatabaseFactory; import org.thoughtcrime.securesms.database.MmsSmsColumns; import org.thoughtcrime.securesms.database.MmsSmsDatabase; import org.thoughtcrime.securesms.database.SmsDatabase; import org.thoughtcrime.securesms.database.model.MessageRecord; import org.thoughtcrime.securesms.util.LRUCache; import java.lang.ref.SoftReference; import java.util.Collections; import java.util.HashSet; import java.util.Locale; import java.util.Map; import java.util.Set; import org.thoughtcrime.securesms.ConversationFragment.SelectionClickListener; /** * A cursor adapter for a conversation thread. Ultimately * used by ComposeMessageActivity to display a conversation * thread in a ListActivity. * * @author Moxie Marlinspike * */ public class ConversationAdapter extends CursorAdapter implements AbsListView.RecyclerListener { private static final int MAX_CACHE_SIZE = 40; private final Map<String, SoftReference<MessageRecord>> messageRecordCache = Collections .synchronizedMap(new LRUCache<String, SoftReference<MessageRecord>>(MAX_CACHE_SIZE)); public static final int MESSAGE_TYPE_OUTGOING = 0; public static final int MESSAGE_TYPE_INCOMING = 1; public static final int MESSAGE_TYPE_GROUP_ACTION = 2; private final Set<MessageRecord> batchSelected = Collections.synchronizedSet(new HashSet<MessageRecord>()); private final SelectionClickListener selectionClickListener; private final Context context; private final MasterSecret masterSecret; private final Locale locale; private final boolean groupThread; private final boolean pushDestination; private final LayoutInflater inflater; public ConversationAdapter(Context context, MasterSecret masterSecret, Locale locale, SelectionClickListener selectionClickListener, boolean groupThread, boolean pushDestination) { super(context, null, 0); this.context = context; this.masterSecret = masterSecret; this.locale = locale; this.selectionClickListener = selectionClickListener; this.groupThread = groupThread; this.pushDestination = pushDestination; this.inflater = LayoutInflater.from(context); } @Override public void bindView(View view, Context context, Cursor cursor) { ConversationItem item = (ConversationItem) view; long id = cursor.getLong(cursor.getColumnIndexOrThrow(SmsDatabase.ID)); String type = cursor.getString(cursor.getColumnIndexOrThrow(MmsSmsDatabase.TRANSPORT)); MessageRecord messageRecord = getMessageRecord(id, cursor, type); item.set(masterSecret, messageRecord, locale, batchSelected, selectionClickListener, groupThread, pushDestination); } @Override public void changeCursor(Cursor cursor) { messageRecordCache.clear(); super.changeCursor(cursor); } @Override public View newView(Context context, Cursor cursor, ViewGroup parent) { View view; int type = getItemViewType(cursor); switch (type) { case ConversationAdapter.MESSAGE_TYPE_OUTGOING: view = inflater.inflate(R.layout.conversation_item_sent, parent, false); break; case ConversationAdapter.MESSAGE_TYPE_INCOMING: view = inflater.inflate(R.layout.conversation_item_received, parent, false); break; case ConversationAdapter.MESSAGE_TYPE_GROUP_ACTION: view = inflater.inflate(R.layout.conversation_item_activity, parent, false); break; default: throw new IllegalArgumentException("unsupported item view type given to ConversationAdapter"); } return view; } @Override public int getViewTypeCount() { return 3; } @Override public int getItemViewType(int position) { Cursor cursor = (Cursor) getItem(position); return getItemViewType(cursor); } private int getItemViewType(Cursor cursor) { long id = cursor.getLong(cursor.getColumnIndexOrThrow(MmsSmsColumns.ID)); String type = cursor.getString(cursor.getColumnIndexOrThrow(MmsSmsDatabase.TRANSPORT)); MessageRecord messageRecord = getMessageRecord(id, cursor, type); if (messageRecord.isGroupAction()) return MESSAGE_TYPE_GROUP_ACTION; else if (messageRecord.isOutgoing()) return MESSAGE_TYPE_OUTGOING; else return MESSAGE_TYPE_INCOMING; } private MessageRecord getMessageRecord(long messageId, Cursor cursor, String type) { SoftReference<MessageRecord> reference = messageRecordCache.get(type + messageId); if (reference != null) { MessageRecord record = reference.get(); if (record != null) return record; } MmsSmsDatabase.Reader reader = DatabaseFactory.getMmsSmsDatabase(context).readerFor(cursor, masterSecret); MessageRecord messageRecord = reader.getCurrent(); messageRecordCache.put(type + messageId, new SoftReference<MessageRecord>(messageRecord)); return messageRecord; } public void close() { this.getCursor().close(); } public void toggleBatchSelected(MessageRecord messageRecord) { if (batchSelected.contains(messageRecord)) { batchSelected.remove(messageRecord); } else { batchSelected.add(messageRecord); } } public Set<MessageRecord> getBatchSelected() { return batchSelected; } @Override public void onMovedToScrapHeap(View view) { ((ConversationItem) view).unbind(); } }