TermTreePane.java

/* 
** Author(s): Miguel Calejo
** Contact:   interprolog@declarativa.com, http://www.declarativa.com
** Copyright (C) Declarativa, Portugal, 2000-2002
** Use and distribution, without any warranties, under the terms of the 
** GNU Library General Public License, readable in http://www.fsf.org/copyleft/lgpl.html
*/
package com.declarativa.interprolog.gui;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
public class TermTreePane extends JPanel{
        JList[] lists;
        TermTreeModel model;
        Object[] levelTitles;
        TermTreePane(TermTreeModel m, Object[] levelTitles){
                setLayout(new BorderLayout());
                if (m==null) 
                        throw new RuntimeException("Null model in TermTreeWindow");
                int nLevels = m.depth();
                if (nLevels<2) 
                        throw new RuntimeException("Bad model in TermTreeWindow:"+m);
                if (levelTitles==null) levelTitles = new String[0];
                this.levelTitles = levelTitles;
                
                lists = new JList[nLevels];
                model=m;
                String[] dummy = {"     "};
                for (int level=0; level<nLevels; level++){
                        final JList list = new JList(dummy);
                        lists[level] = list;
                        if (level<nLevels-1) list.addListSelectionListener(new ListHandler(level));
                list.addMouseListener(new MouseAdapter() {
                        public void mouseClicked(MouseEvent e) {
                                if (e.getClickCount() == 2) {
                                int index = list.locationToIndex(e.getPoint());
                                TermListModel lm = (TermListModel)(list.getModel());
                                if (index != -1) new TermModelWindow(lm.terms[index]);
                                }
                        };
                });

                }
                lists[0].setModel(m.topList());
                if (nLevels>2){
                        JSplitPane current = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, true, 
                                paneForList(0), paneForList(1));
                        current.setDividerLocation(0.5);
                        for (int level=2;level<nLevels-1;level++){
                                current = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, true, current, paneForList(level)); 
                                current.setDividerLocation((float)level/(nLevels-1));
                        }
                        add("Center",current);
                }
                else add("Center",paneForList(0));
        }
        
        JComponent paneForList(int L){
                JPanel temp = new JPanel(new BorderLayout());
                temp.add("Center",new JScrollPane(lists[L]));
                if (L>levelTitles.length-2)
                        temp.add("North",new JLabel(" "));
                else
                        temp.add("North",new JLabel(levelTitles[L+1].toString()));
                return temp;
        }
        class ListHandler implements ListSelectionListener{
                int position;
                ListHandler(int i){position=i;}
                public void valueChanged(ListSelectionEvent e){ // repaint() needed !
                        JList list = (JList)(e.getSource());
                        
                        if (!e.getValueIsAdjusting() & list.getSelectedIndex()!=-1){
                                lists[position+1].setModel(findModel(position).topList());
                                clearRightLists();
                                repaintRight();
                        }
                }
                
                void clearRightLists(){ 
                        for(int level=position+2; level<lists.length; level++){
                                lists[level].setListData(new Object[0]);
                        }
                }
                void repaintRight(){
                        for(int level=position+1; level<lists.length; level++){
                                lists[level].repaint();
                                //lists[level].clearSelection();
                                //lists[level].revalidate();
                        }
                }
                
                TermTreeModel findModel(int position){ // all JLists have a selection up to position
                        TermTreeModel temp = model.children[lists[0].getSelectedIndex()];
                        for (int level=1; level<=position; level++){
                                temp=temp.children[lists[level].getSelectedIndex()];
                        }
                        return temp;
                }
        }
}

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