ktablecelleditorcombo.java

ktable 是一个由java开发的,对控制报表的项目,它最大的特点是使用独特的算法,能支持巨大的报表(千万以上?).

/*
 * Copyright (C) 2004 by Friederich Kupzog Elektronik & Software
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
    
    Authors: Friederich Kupzog
             Lorenz Maierhofer
    [e-mail]
    www.kupzog.de/fkmk
*/
package de.kupzog.ktable.editors;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CCombo;
import org.eclipse.swt.events.KeyAdapter;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.TraverseEvent;
import org.eclipse.swt.events.TraverseListener;
import org.eclipse.swt.graphics.Cursor;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;

import de.kupzog.ktable.KTable;
import de.kupzog.ktable.KTableCellEditor;

/**
 * A combobox cell editor. 
 * 
 * @author Friederich Kupzog
 */
public class KTableCellEditorCombo extends KTableCellEditor {
	private CCombo m_Combo;
	private String m_Items[];
	private Cursor m_ArrowCursor = new Cursor(Display.getDefault(), SWT.CURSOR_ARROW);
    
    private KeyAdapter keyListener = new KeyAdapter() {
        public void keyPressed(KeyEvent e) {
            try {
                onKeyPressed(e);
            } catch (Exception ex) {
                // Do nothing
            }
            e.doit = false;
       }
    };
    
    private TraverseListener travListener = new TraverseListener() {
        public void keyTraversed(TraverseEvent e) {
            onTraverse(e);
        }
    };

	public void open(KTable table, int row, int col, Rectangle rect) {
		super.open(table, row, col, rect);
		String content =m_Model.getContentAt(m_Col, m_Row).toString(); 
		m_Combo.setText(content);
		m_Combo.setSelection(new Point(0, content.length()));
	}

	public void close(boolean save) {
        if (save)
            m_Model.setContentAt(m_Col, m_Row, m_Combo.getText());
        m_Combo.removeKeyListener(keyListener);
        m_Combo.removeTraverseListener(travListener);
        super.close(save);
        m_Combo = null;
        m_ArrowCursor.dispose();
	}

	protected Control createControl() {
		m_Combo = new CCombo(m_Table, SWT.READ_ONLY);
		m_Combo.setBackground(Display.getCurrent().getSystemColor(SWT.COLOR_LIST_BACKGROUND));
		
		if (m_Items != null)
			m_Combo.setItems(m_Items);
        
        m_Combo.addKeyListener(keyListener);        
        m_Combo.addTraverseListener(travListener);
        
		m_Combo.setCursor(m_ArrowCursor);
		return m_Combo;
	}
	
	/**
	 * Overwrite the onTraverse method to ignore arrowup and arrowdown
	 * events so that they get interpreted by the editor control.<p>
	 * Comment that out if you want the up and down keys move the editor.<br>
	 * Hint by David Sciamma.
	 */
	protected void onTraverse(TraverseEvent e)
    {
        // set selection to the appropriate next element:
        switch (e.keyCode)
        {
            case SWT.ARROW_UP: // Go to previous item
            case SWT.ARROW_DOWN: // Go to next item
            {
                // Just don't treat the event
                break;
            }
            default: {
                super.onTraverse(e);
                break;
            }
        }
    } 
	
	public void setBounds(Rectangle rect) 
	{
		super.setBounds(new Rectangle(rect.x, rect.y+1,
									  rect.width, rect.height-2));
	}

	public void setItems(String items[]) {
		m_Items = items;
	}

    /* (non-Javadoc)
     * @see de.kupzog.ktable.KTableCellEditor#setContent(java.lang.String)
     */
    public void setContent(Object content) {
       if (content instanceof Integer) {
           m_Combo.select(((Integer)content).intValue());
       } else if (content instanceof String) {
           setSelectionToClosestMatch((String)content);
       } else {
           setSelectionToClosestMatch(content.toString());
       }
    }
	
    private void setSelectionToClosestMatch(String content) {
        content = content.toLowerCase();
        
        String[] citems = m_Combo.getItems();
        String[] items = new String[citems.length];
        for (int i=0; i<citems.length; i++)
            items[i] = citems[i].toLowerCase();
        
        for (int length=content.length(); length>=0; length--) {
            String part = content.substring(0, length);
            for (int i=0; i<items.length; i++) 
                if (items[i].startsWith(part)) {
                    m_Combo.select(i);
                    return;
                }
        }
    }
}