1 /*

     2  * Hedgewars for Android. An Android port of Hedgewars, a free turn based strategy game

     3  * Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.com>

     4  *

     5  * This program is free software; you can redistribute it and/or

     6  * modify it under the terms of the GNU General Public License

     7  * as published by the Free Software Foundation; either version 2

     8  * of the License, or (at your option) any later version.

     9  *

    10  * This program is distributed in the hope that it will be useful,

    11  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    13  * GNU General Public License for more details.

    14  *

    15  * You should have received a copy of the GNU General Public License

    16  * along with this program; if not, write to the Free Software

    17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

    18  */

    19 

    20 package org.hedgewars.hedgeroid;

    21 

    22 import java.util.ArrayList;

    23 import java.util.Collection;

    24 import java.util.List;

    25 

    26 import org.hedgewars.hedgeroid.netplay.MessageLog;

    27 

    28 import android.content.Context;

    29 import android.text.method.LinkMovementMethod;

    30 import android.view.View;

    31 import android.view.ViewGroup;

    32 import android.widget.AbsListView.LayoutParams;

    33 import android.widget.BaseAdapter;

    34 import android.widget.TextView;

    35 

    36 /**

    37  * Optimization: ListView is smart enough to try re-using the same view for an item

    38  * with the same ID, but it still calls getView for those items when the list changes.

    39  * Since lines with a given ID never change in our chatlog, we can avoid the effort

    40  * of TextView.setText in many cases by checking if the view is already set up for the

    41  * line with the right ID - but to do that, the view needs to remember the ID it's

    42  * holding the text for. That's what the LoglineView does. 

    43  */

    44 class LoglineView extends TextView {

    45 	long chatlogId = -1;

    46 	

    47 	public LoglineView(Context context) {

    48 		super(context);

    49 	}

    50 }

    51 

    52 /**

    53  * For performance reasons, the chatlog is implemented as ListView instead of a

    54  * single TextView (although I later learned that TextView might also have

    55  * facilities for efficient appending with limited backlog... oh well, this

    56  * works). Every chat line is a line in the ListView, and this adapter prepares

    57  * the textviews from a messagelog in an efficient way.

    58  */

    59 public class ChatlogAdapter extends BaseAdapter implements MessageLog.Listener {

    60 	long idOffset = 0;

    61 	private List<CharSequence> log = new ArrayList<CharSequence>();

    62 	private Context context;

    63 	

    64 	public ChatlogAdapter(Context context) {

    65 		this.context = context;

    66 	}

    67 	

    68 	public int getCount() {

    69 		return log.size();

    70 	}

    71 

    72 	public Object getItem(int position) {

    73 		return log.get(position);

    74 	}

    75 

    76 	public long getItemId(int position) {

    77 		return position+idOffset;

    78 	}

    79 

    80 	public boolean hasStableIds() {

    81 		return true;

    82 	}

    83 

    84 	public void clear() {

    85 		idOffset += log.size();

    86 		log.clear();

    87 		notifyDataSetChanged();

    88 	}

    89 	

    90 	public void lineAdded(CharSequence text) {

    91 		log.add(text);

    92 		notifyDataSetChanged();

    93 	}

    94 	

    95 	public void lineRemoved() {

    96 		log.remove(0);

    97 		idOffset += 1;

    98 		notifyDataSetChanged();

    99 	}

   100 	

   101 	public void setLog(Collection<CharSequence> log) {

   102 		idOffset += log.size();

   103 		this.log = new ArrayList<CharSequence>(log);

   104 		notifyDataSetChanged();

   105 	}

   106 	

   107 	public View getView(int position, View convertView, ViewGroup parent) {

   108 		LoglineView v = (LoglineView)convertView;

   109 		if (v == null) {

   110 			v = new LoglineView(context);

   111 			v.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));

   112 			v.setMovementMethod(LinkMovementMethod.getInstance());

   113 		}

   114 		long id = getItemId(position);

   115 		if(id != v.chatlogId) {

   116 			v.setText(log.get(position));

   117 			v.chatlogId = id;

   118 		}

   119 		return v;

   120 	}

   121 }