随手写个例子,仅供参考:import java.awt.*;
import java.awt.event.*;
import javax.swing.*;public class GraphicsDrawLine { public static void main(String[] args) {
MyFrame fr = new MyFrame();
fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
fr.show();
}
}class MyFrame extends JFrame {
int a, b, c, d;
public MyFrame() {
final MyPanel p = new MyPanel();
setTitle("Test line-drawing");
setSize(800,600);
getContentPane().add(p);
}
}class MyPanel extends JPanel {
int a, b, c, d;
public MyPanel() {
addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent e) {
a = Integer.parseInt(JOptionPane.showInputDialog("x1: ", "0"));
b = Integer.parseInt(JOptionPane.showInputDialog("y1: ", "0"));
c = Integer.parseInt(JOptionPane.showInputDialog("x2: ", "500"));
d = Integer.parseInt(JOptionPane.showInputDialog("y2: ", "500"));
repaint();
}
});
}
public void paint(Graphics g) {
super.paint(g);
g.drawLine(a,b,c,d);
}
}
import java.awt.event.*;
import javax.swing.*;public class GraphicsDrawLine { public static void main(String[] args) {
MyFrame fr = new MyFrame();
fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
fr.show();
}
}class MyFrame extends JFrame {
int a, b, c, d;
public MyFrame() {
final MyPanel p = new MyPanel();
setTitle("Test line-drawing");
setSize(800,600);
getContentPane().add(p);
}
}class MyPanel extends JPanel {
int a, b, c, d;
public MyPanel() {
addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent e) {
a = Integer.parseInt(JOptionPane.showInputDialog("x1: ", "0"));
b = Integer.parseInt(JOptionPane.showInputDialog("y1: ", "0"));
c = Integer.parseInt(JOptionPane.showInputDialog("x2: ", "500"));
d = Integer.parseInt(JOptionPane.showInputDialog("y2: ", "500"));
repaint();
}
});
}
public void paint(Graphics g) {
super.paint(g);
g.drawLine(a,b,c,d);
}
}
解决方案 »
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比我要的结果还更好,居然可以点鼠标多次画线的.
不过有个地方看不懂耶
在倒数第七行
怎么得加上 ");"才可以运行呢
只有一个右括弧啊
是起什么作用的呢