progressbar.java

打印管理程序,测试完全通过.windows开发环境.

/*
    $Author: $
    $Date: $
    $Revision: $
    $NoKeywords: $
*/
package jp.co.ntl.awt;

import java.awt.Component;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.Image;
import java.awt.FontMetrics;

import jp.co.ntl.Util;

public class ProgressBar extends Component {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
    private float ratio;
    private Color progressColor;
    private String text;

    private Image imageBuffer = null;
    private Graphics graphicsImage = null;

    public ProgressBar() {
        setSize(100, 20);
        progressColor = Color.red;
        setBackground(Color.blue);
        setForeground(Color.white);
    }
    
    public void setRatio(float ratio) {
        this.ratio = ratio;
        repaint();
    }
    
    public void setText(String text) {
        this.text = text;
        repaint();
    }
    
    public void setProgressColor(Color progressColor) {
        this.progressColor = progressColor;
        repaint();
    }
    
    public void update(Graphics g) {
        paint(g);
    }
        
	public void invalidate() {
		super.invalidate();
		imageBuffer = null;
		if (graphicsImage != null) {
		    graphicsImage.dispose();
		}
	}

    public void paint(Graphics g) {
        Dimension d = getSize();
        int width = d.width;
        int height = d.height;
        if (imageBuffer == null) {
			imageBuffer = createImage(width, height);
			graphicsImage = imageBuffer.getGraphics();
		}
        super.paint(graphicsImage);

        int sx =  (int)(width * ratio);
        graphicsImage.setColor(progressColor);
        graphicsImage.fillRect(0, 0, sx, height);
        graphicsImage.setColor(getBackground());
        graphicsImage.fillRect(sx, 0, width - sx, height);
        if (text != null) {
            FontMetrics fm = g.getFontMetrics();
            int bx = Util.basePointX(fm, text, width);
            int by = Util.basePointY(fm, text, height);
            graphicsImage.setColor(getForeground());
            graphicsImage.drawString(text, bx, by);
        }
        g.drawImage(imageBuffer, 0, 0, this);
    }
}