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举一个画直线的例子
摘要: 举一个画直线的例子
用main()
#include
void main()
{
for(int i_c=0;i_c<25;i_c++) printf("-");
}
楼上C暴强...
用java写!
public void paint(Graphics g)
{
g.drawLine(10,10,50,10);
}
一楼是我的偶像,强
class xxx
public static void main(String args[])
{
for(int i_c=0;i_c<25;i_c++) System.out.print("-");
}
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.awt.image.*;
public class DrawLine extends JFrame
{
public DrawLine()
{
int x1,y1,x2,y2;
this.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
x1 = e.getX();
y1 = e.getY();
}
public void mouseReleased(MouseEvent e)
{
x2 = e.getX();
y2 = e.getY();
getGraphics().drawLine(x1,y1,x2,y2);//此处getGraphics()为什么不对呢??
}
}
);
}
public static void main(String[] args)
{
DrawLine fm = new DrawLine();
fm.setSize(300,300);
fm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
fm.setVisible(true);
}
}
楼上的你没继承Graphics类 不能这样用吧
哦 楼上楼上的你的程式没问题
int x1,y1,x2,y2;放到构造方法之外编译没错误
class xxx
public static void main(String args[])
{
System.out.print("-----------------------------------------");
}
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.awt.image.*;
class DrawLine extends JFrame
{
int x1,y1,x2,y2;
public DrawLine()
{
this.setSize(300,300);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
//int x1,y1,x2,y2;
this.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
x1 = e.getX();
y1 = e.getY();
}
public void mouseReleased(MouseEvent e)
{
x2 = e.getX();
y2 = e.getY();
getGraphics().drawLine(x1,y1,x2,y2);//此处getGraphics()为什么不对呢??
}
});
}
public static void main(String[] args)
{
DrawLine fm = new DrawLine();
//fm.setSize(300,300);
//fm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//fm.setVisible(true);
}
}
直线画好了吗?