project_files/Android-build/SDL-android-project/src/org/hedgewars/hedgeroid/ChatlogAdapter.java
/*
* Hedgewars for Android. An Android port of Hedgewars, a free turn based strategy game
* Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.com>
*
* 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 2
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.hedgewars.hedgeroid;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.hedgewars.hedgeroid.netplay.MessageLog;
import android.content.Context;
import android.text.method.LinkMovementMethod;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView.LayoutParams;
import android.widget.BaseAdapter;
import android.widget.TextView;
/**
* Optimization: ListView is smart enough to try re-using the same view for an item
* with the same ID, but it still calls getView for those items when the list changes.
* Since lines with a given ID never change in our chatlog, we can avoid the effort
* of TextView.setText in many cases by checking if the view is already set up for the
* line with the right ID - but to do that, the view needs to remember the ID it's
* holding the text for. That's what the LoglineView does.
*/
class LoglineView extends TextView {
long chatlogId = -1;
public LoglineView(Context context) {
super(context);
}
}
/**
* For performance reasons, the chatlog is implemented as ListView instead of a
* single TextView (although I later learned that TextView might also have
* facilities for efficient appending with limited backlog... oh well, this
* works). Every chat line is a line in the ListView, and this adapter prepares
* the textviews from a messagelog in an efficient way.
*/
public class ChatlogAdapter extends BaseAdapter implements MessageLog.Listener {
long idOffset = 0;
private List<CharSequence> log = new ArrayList<CharSequence>();
private Context context;
public ChatlogAdapter(Context context) {
this.context = context;
}
public int getCount() {
return log.size();
}
public Object getItem(int position) {
return log.get(position);
}
public long getItemId(int position) {
return position+idOffset;
}
public boolean hasStableIds() {
return true;
}
public void clear() {
idOffset += log.size();
log.clear();
notifyDataSetChanged();
}
public void lineAdded(CharSequence text) {
log.add(text);
notifyDataSetChanged();
}
public void lineRemoved() {
log.remove(0);
idOffset += 1;
notifyDataSetChanged();
}
public void setLog(Collection<CharSequence> log) {
idOffset += log.size();
this.log = new ArrayList<CharSequence>(log);
notifyDataSetChanged();
}
public View getView(int position, View convertView, ViewGroup parent) {
LoglineView v = (LoglineView)convertView;
if (v == null) {
v = new LoglineView(context);
v.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
v.setMovementMethod(LinkMovementMethod.getInstance());
}
long id = getItemId(position);
if(id != v.chatlogId) {
v.setText(log.get(position));
v.chatlogId = id;
}
return v;
}
}