bardiagramcellrenderer.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
 * 
 */
package de.kupzog.ktable.renderers;

import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Rectangle;

import de.kupzog.ktable.KTableModel;

/**
 * 
 * @author Lorenz Maierhofer <[e-mail]>
 */
public class BarDiagramCellRenderer extends DefaultCellRenderer {
    
    /**
     * @param style The style bits to use.
     * Currently supported are:<br>
     * - INDICATION_FOCUS<br>
     * - INDICATION_FOCUS_ROW<br>
     * - INDICATION_GRADIENT
     */
    public BarDiagramCellRenderer(int style) {
        super(style);
    }
    
    /* (non-Javadoc)
     * @see de.kupzog.ktable.KTableCellRenderer#getOptimalWidth(org.eclipse.swt.graphics.GC, int, int, java.lang.Object, boolean)
     */
    public int getOptimalWidth(GC gc, int col, int row, Object content, boolean fixed, KTableModel model) {
        return 20;
    }

    /** 
     * @param content The content is expected to be a Float value between 0 and 1 that represents
     * the fraction of the cell width that should be used for the bar.
     * @see de.kupzog.ktable.KTableCellRenderer#drawCell(GC, Rectangle, int, int, Object, boolean, boolean, boolean, KTableModel)
     */
    public void drawCell(GC gc, Rectangle rect, int col, int row, Object content, 
            boolean focus, boolean fixed, boolean clicked, KTableModel model) {
        
        if (focus && (m_Style & INDICATION_FOCUS)!=0) {
            rect = drawDefaultSolidCellLine(gc, rect, COLOR_LINE_LIGHTGRAY, COLOR_LINE_LIGHTGRAY);
            drawBar(gc, rect, content, COLOR_BGFOCUS, getForeground());            
            gc.drawFocus(rect.x, rect.y, rect.width, rect.height);
            
        } else if (focus && (m_Style & INDICATION_FOCUS_ROW)!=0) {
            rect = drawDefaultSolidCellLine(gc, rect, COLOR_BGROWFOCUS, COLOR_BGROWFOCUS);
            Color defaultBg = COLOR_BACKGROUND;
            setDefaultBackground(COLOR_BGROWFOCUS);
            drawBar(gc, rect, content, getBackground(), getForeground());
            setDefaultBackground(defaultBg);
            
        } else {
            rect = drawDefaultSolidCellLine(gc, rect, COLOR_LINE_LIGHTGRAY, COLOR_LINE_LIGHTGRAY);
            drawBar(gc, rect, content, getBackground(), getForeground());
        }
    }

    /**
     * @param gc
     * @param rect
     * @param m_fraction
     * @param background
     */
    protected void drawGradientBar(GC gc, Rectangle rect, float m_fraction, Color background, Color foreground) {
        int barWidth = Math.round(rect.width*m_fraction);
        gc.setForeground(background);
        gc.setBackground(foreground);
        gc.fillGradientRectangle(rect.x, rect.y, barWidth, rect.height, false);
        gc.setBackground(COLOR_BACKGROUND);
        gc.fillRectangle(rect.x+barWidth, rect.y, rect.width-barWidth, rect.height);
    }

    /**
     * @param gc
     * @param rect
     * @param background
     * @param foreground
     * @param m_fraction
     */
    protected void drawNormalBar(GC gc, Rectangle rect, Color background, Color foreground, float m_fraction) {
        int barWidth = Math.round(rect.width*m_fraction);
        gc.setBackground(foreground);
        gc.fillRectangle(rect.x, rect.y, barWidth, rect.height);
        gc.setBackground(background);
        gc.fillRectangle(rect.x+barWidth, rect.y, rect.width-barWidth, rect.height);
    }
    
    /**
     * @param gc
     * @param rect
     * @param m_fraction
     * @param background
     */
    protected void drawBar(GC gc, Rectangle rect, Object content, Color background, Color foreground) {
        float m_fraction;
        if (content instanceof Float)
            m_fraction = ((Float)content).floatValue();
        else if (content instanceof Double)
            m_fraction = ((Double)content).floatValue();
        else if (content instanceof IPercentage)
            m_fraction = ((IPercentage)content).getPercentage();
        else m_fraction=0;
        
        if (m_fraction>1) m_fraction=1;
        if (m_fraction<0) m_fraction=0;
        
        if ((m_Style & INDICATION_GRADIENT) != 0)
            drawGradientBar(gc, rect, m_fraction, background, foreground);
        else
            drawNormalBar(gc, rect, background, foreground, m_fraction);
    }
}