ktablecelleditorcheckbox2.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,  [e-mail], www.kupzog.de/fkmk
 Lorenz Maierhofer, [e-mail]
 
 */
package de.kupzog.ktable.editors;

import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;

import de.kupzog.ktable.KTable;
import de.kupzog.ktable.SWTX;

/**
 * This class is an implementation of KTableCellEditorCheckbox that
 * simply inverts a boolean cell value. <p>
 * In contrast to KTableCellEditorCheckbox, this class only allows
 * its activation on a mouse event when the user clicked on a special 
 * area inside the cell. The area itself can be specified when calling the
 * constructor.   
 * 
 * @see de.kupzog.ktable.editors.KTableCellEditorCheckbox
 * @see de.kupzog.ktable.cellrenderers.CheckableCellRenderer
 * 
 * @author Lorenz Maierhofer <[e-mail]>
 */
public class KTableCellEditorCheckbox2 extends KTableCellEditorCheckbox {

    private Point m_Active;
    private int m_hAlign, m_vAlign;
    
    /**
     * Creates a checkbox celleditor that is only sensible for mouse activation 
     * in the specified area.
     * @param activeArea The size of the active area inside the cell. 
     *        x means width, y means height.
     * @param hAlign The horizontal alignment of the active 
     * 		  area inside the cell. Defined in the SWTX class.
     *        Possible values: ALIGN_HORIZONTAL_CENTER, 
     *                         ALIGN_HORIZONTAL_LEFT, 
     * 					       ALIGN_HORIZONTAL_RIGHT
     * @param vAlign The vertical alignment of the active area 
     * 		  inside the cell. Defined in the SWTX class.
     *        Possible values: ALIGN_VERTICAL_CENTER, 
     *                         ALIGN_VERTICAL_BOTTOM, 
     * 					       ALIGN_VERTICAL_TOP
     * @throws ClassCastException if an invalid input is given.
     */
    public KTableCellEditorCheckbox2(Point activeArea, int hAlign, int vAlign) {
        if (activeArea==null || 
                !isValidHAlignment(hAlign) || !isValidVAlignment(vAlign))
            throw new ClassCastException("Check the parameters given to KTableCellEditorCheckbox2!");
            
        m_Active = activeArea;
        m_hAlign = hAlign;
        m_vAlign = vAlign;
    }
    
    /**
     * Checks wether the given horizontal alignment parameter is valid.
     * @param align The alignment to check
     * @return True if the alignment value is valid.
     */
    private boolean isValidHAlignment(int align) {
        if (align==SWTX.ALIGN_HORIZONTAL_CENTER || 
            align==SWTX.ALIGN_HORIZONTAL_LEFT  || 
            align==SWTX.ALIGN_HORIZONTAL_RIGHT)
            return true;
        return false;
    }
    
    /**
     * Checks wether the given vertical alignment parameter is valid.
     * @param align The alignment to check
     * @return True if the alignment value is valid.
     */
    private boolean isValidVAlignment(int align) {
        if (align==SWTX.ALIGN_VERTICAL_TOP || 
            align==SWTX.ALIGN_VERTICAL_CENTER  || 
            align==SWTX.ALIGN_VERTICAL_BOTTOM)
            return true;
        return false;
    }
    
    /**
	 * Is called when an activation is triggered via a mouse click.<p> 
	 * If false is returned, the editor does not get activated.<p>
	 * All coordinates must be relative to the KTable.
     * @param clickLocation The point where the mouseclick occured.
     * @return Returns true if the editor activation should happen.
	 */
	public boolean isApplicable(int eventType, KTable table, int col, int row, 
			Point clickLocation, String keyInput, int stateMask) {
		if (eventType == SINGLECLICK) {
			// compute active location inside the cellBoundary:
			Rectangle active = new Rectangle(0, 0, m_Active.x, m_Active.y);
			Rectangle cellBoundary = table.getCellRect(col, row);
			if (cellBoundary.width<active.width) active.width = cellBoundary.width;
			if (cellBoundary.height<active.height) active.height = cellBoundary.height;
			
			if (m_hAlign == SWTX.ALIGN_HORIZONTAL_LEFT)
				active.x = cellBoundary.x;
			else if (m_hAlign == SWTX.ALIGN_HORIZONTAL_RIGHT)
				active.x = cellBoundary.x+cellBoundary.width-active.width;
			else // center
				active.x = cellBoundary.x+(cellBoundary.width-active.width)/2;
			
			if (m_vAlign == SWTX.ALIGN_VERTICAL_TOP)
				active.y = cellBoundary.y;
			else if (m_vAlign == SWTX.ALIGN_VERTICAL_BOTTOM) 
				active.y = cellBoundary.y+cellBoundary.height-active.height;
			else 
				active.y = cellBoundary.y+(cellBoundary.height-active.height)/2;
			
			// check if clickLocation is inside the specified active area:
			if (active.contains(clickLocation))
				return true;
			return false;
		} else
			return true;
	}
}