nonflickerpanel.java

一个完整的

// Decompiled by DJ v2.9.9.60 Copyright 2000 Atanas Neshkov  Date: 2002-12-03 18:43:38
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// Decompiler options: packimports(3) 
// Source File Name:   NonFlickerPanel.java

package cn.com.fcsoft.chart;

import java.awt.*;

public class NonFlickerPanel extends Panel
{

    public void invalidate()
    {
        super.invalidate();
        offscreen = null;
    }

    public NonFlickerPanel()
    {
    }

    public NonFlickerPanel(LayoutManager layoutmanager)
    {
        super(layoutmanager);
    }

    public void paint(Graphics g)
    {
        Dimension dimension = getSize();
        if(offscreen == null)
        {
            dimension.width = Math.max(1, dimension.width);
            dimension.height = Math.max(1, dimension.height);
            offscreen = createImage(dimension.width, dimension.height);
        }
        try
        {
            Graphics g1 = offscreen.getGraphics();
            g1.setClip(0, 0, dimension.width, dimension.height);
            super.paint(g1);
            g.drawImage(offscreen, 0, 0, null);
            g1.dispose();
        }
        catch(NullPointerException _ex) { }
    }

    public void update(Graphics g)
    {
        paint(g);
    }

    private Image offscreen;
}