Applet能否绘制曲线图

以前网上搜集的，你可参考：
SmoothedCurveApplet.java/////////////////////////////////////////////
//本程序说明:请用把本文件夹加入PWS或IIS后,用IE打开SmoothedCurve.asp
/////////////////////////////////////////////
import java.awt.*;
import javax.swing.*;class SmoothedCurvePanel extends JPanel
{
private int x1=22,y1=10; //坐标点1的x,y
private int x2=790,y2=580;  //坐标点2的x,y
    private int iCount=6;       //采样个数
    private int[][] iInpoint;   //坐标x,y的存储数组

public SmoothedCurvePanel()
{
iInpoint=new int[iCount][2];
iInpoint[0][0]=20; iInpoint[0][1]=20;
iInpoint[1][0]=40; iInpoint[1][1]=40;
iInpoint[2][0]=80; iInpoint[2][1]=80;
iInpoint[3][0]=200; iInpoint[3][1]=200;
iInpoint[4][0]=250; iInpoint[4][1]=150;
iInpoint[5][0]=300; iInpoint[5][1]=80;
    }

public void paintComponent(Graphics g)
{
super.paintComponent(g);
drawCircle(g);
}

//画光滑曲线
public void drawCircle(Graphics g)
{
for(int i=0;i<iCount;i++)
if(iCount!=0 && i!=iCount-1)
//等x或y
if((iInpoint[i+1][0]-iInpoint[i][0])==0 || (iInpoint[i+1][1]-iInpoint[i][1])==0)
{
g.drawLine(x1+iInpoint[i][0],y2-iInpoint[i][1],x1+iInpoint[i+1][0],y2-iInpoint[i+1][1]);//画直线
}
else
//前升
if((iInpoint[i+1][0]-iInpoint[i][0])>0 && (iInpoint[i+1][1]-iInpoint[i][1])>0)
{
g.drawArc(x1+iInpoint[i][0]-(iInpoint[i+1][0]-iInpoint[i][0])/2,y2-iInpoint[i+1][1],iInpoint[i+1][0]-iInpoint[i][0],iInpoint[i+1][1]-iInpoint[i][1],270,90);
g.drawArc((x1+iInpoint[i][0])+(iInpoint[i+1][0]-iInpoint[i][0])/2,y2-iInpoint[i+1][1],iInpoint[i+1][0]-iInpoint[i][0],iInpoint[i+1][1]-iInpoint[i][1],90,90);
}
else
//前降
if((iInpoint[i+1][0]-iInpoint[i][0])>0 && (iInpoint[i+1][1]-iInpoint[i][1])<0)
{
g.drawArc((x1+iInpoint[i][0])-(iInpoint[i+1][0]-iInpoint[i][0])/2,(y2-iInpoint[i][1]),iInpoint[i+1][0]-iInpoint[i][0],-(iInpoint[i+1][1]-iInpoint[i][1]),0,90);
g.drawArc((x1+iInpoint[i][0])+(iInpoint[i+1][0]-iInpoint[i][0])/2,(y2-iInpoint[i][1]),iInpoint[i+1][0]-iInpoint[i][0],-(iInpoint[i+1][1]-iInpoint[i][1]),180,90);
}
else
//后升
if((iInpoint[i+1][0]-iInpoint[i][0])<0 && (iInpoint[i+1][1]-iInpoint[i][1])>0)
{
g.drawArc((x1+iInpoint[i+1][0])-(-(iInpoint[i+1][0]-iInpoint[i][0])/2),y2-iInpoint[i+1][1],-(iInpoint[i+1][0]-iInpoint[i][0]),iInpoint[i+1][1]-iInpoint[i][1],0,90);
g.drawArc((x1+iInpoint[i+1][0])-(iInpoint[i+1][0]-iInpoint[i][0])/2,y2-iInpoint[i+1][1],-(iInpoint[i+1][0]-iInpoint[i][0]),iInpoint[i+1][1]-iInpoint[i][1],180,90);
}
else
//后降
if((iInpoint[i+1][0]-iInpoint[i][0])<0 && (iInpoint[i+1][1]-iInpoint[i][1])<0)
{
g.drawArc(x1+iInpoint[i+1][0],(y2-iInpoint[i][1])+(iInpoint[i+1][1]-iInpoint[i][1])/2,-(iInpoint[i+1][0]-iInpoint[i][0]),-(iInpoint[i+1][1]-iInpoint[i][1]),270,90);
g.drawArc(x1+iInpoint[i+1][0],(y2-iInpoint[i][1])-(iInpoint[i+1][1]-iInpoint[i][1])/2,-(iInpoint[i+1][0]-iInpoint[i][0]),-(iInpoint[i+1][1]-iInpoint[i][1]),90,90);
}
}
}public class SmoothedCurveApplet extends JApplet
{
public void init()
{
Container contentPane = getContentPane();
contentPane.add(new SmoothedCurvePanel());
}
}
SmoothedCurve.html<html>
<body>
<OBJECT classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
WIDTH = 800 HEIGHT = 601>
<PARAM NAME = CODE VALUE = "SmoothedCurveApplet" >
<PARAM NAME="type" VALUE="application/x-java-applet;version=1.3">
<PARAM NAME="scriptable" VALUE="false">
<COMMENT>
<EMBED type="application/x-java-applet;version=1.3"  CODE = "SmoothedCurveApplet" WIDTH = 800 HEIGHT = 801  scriptable=false pluginspage="http://java.sun.com/products/plugin/1.3/plugin-install.html"><NOEMBED>
</NOEMBED>
</EMBED>
</COMMENT>
</OBJECT>
</body>
</html>
以下代码是sin曲线图,用了draw函数:
In the following example, all the intelligence concerning painting is in the SineDraw class; the SineWave class simply configures the program and the slider control. Inside SineDraw, the setCycles( ) method provides a hook to allow another object—the slider control, in this case—to control the number of cycles.
//: c13:SineWave.java
// Drawing with Swing, using a JSlider.
// <applet code=SineWave
//  width=700 height=400></applet>
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import com.bruceeckel.swing.*;class SineDraw extends JPanel {
  static final int SCALEFACTOR = 200;
  int cycles;
  int points;
  double[] sines;
  int[] pts;
  SineDraw() { setCycles(5); }
  public void setCycles(int newCycles) {
    cycles = newCycles;
    points = SCALEFACTOR * cycles * 2;
    sines = new double[points];
    pts = new int[points];
    for(int i = 0; i < points; i++) {
      double radians = (Math.PI/SCALEFACTOR) * i;
      sines[i] = Math.sin(radians);
    }
    repaint();
  }
  public void paintComponent(Graphics g) {
    super.paintComponent(g);
    int maxWidth = getWidth();
    double hstep = (double)maxWidth/(double)points;
    int maxHeight = getHeight();
    for(int i = 0; i < points; i++)
      pts[i] = (int)(sines[i] * maxHeight/2 * .95
                     + maxHeight/2);
    g.setColor(Color.red);
    for(int i = 1; i < points; i++) {
      int x1 = (int)((i - 1) * hstep);
      int x2 = (int)(i * hstep);
      int y1 = pts[i-1];
      int y2 = pts[i];
      g.drawLine(x1, y1, x2, y2);
    }
  }
}public class SineWave extends JApplet {
  SineDraw sines = new SineDraw();
  JSlider cycles = new JSlider(1, 30, 5);
  public void init() {
    Container cp = getContentPane();
    cp.add(sines);
    cycles.addChangeListener(new ChangeListener(){
      public void stateChanged(ChangeEvent e) {
        sines.setCycles(
          ((JSlider)e.getSource()).getValue());
      }
    });
    cp.add(BorderLayout.SOUTH, cycles);
  }
  public static void main(String[] args) {
    Console.run(new SineWave(), 700, 400);
  }
} ///:~
注意,import com.bruceeckel.swing.*;
是针对:
//: com:bruceeckel:swing:Console.java
// Tool for running Swing demos from the
// console, both applets and JFrames.
package com.bruceeckel.swing;
import javax.swing.*;
import java.awt.event.*;public class Console {
  // Create a title string from the class name:
  public static String title(Object o) {
    String t = o.getClass().toString();
    // Remove the word "class":
    if(t.indexOf("class") != -1)
      t = t.substring(6);
    return t;
  }
  public static void setupClosing(JFrame frame) {
    // The JDK 1.2 Solution as an
    // anonymous inner class:
    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });
    // The improved solution in JDK 1.3:
    // frame.setDefaultCloseOperation(
    //     EXIT_ON_CLOSE);
  }
  public static void
  run(JFrame frame, int width, int height) {
    setupClosing(frame);
    frame.setSize(width, height);
    frame.setVisible(true);
  }
  public static void
  run(JApplet applet, int width, int height) {
    JFrame frame = new JFrame(title(applet));
    setupClosing(frame);
    frame.getContentPane().add(applet);
    frame.setSize(width, height);
    applet.init();
    applet.start();
    frame.setVisible(true);
  }
  public static void
  run(JPanel panel, int width, int height) {
    JFrame frame = new JFrame(title(panel));
    setupClosing(frame);
    frame.getContentPane().add(panel);
    frame.setSize(width, height);
    frame.setVisible(true);
  }
} ///:~
来自:thinking in java

调试易

Applet能否绘制曲线图

解决方案 »