自学的第五篇博客

Posted 2020-11-24 sunblingbling

利用Jpanel设计一个程序

import java.awt.*;
import java.awt.Container;
import java.awt.FlowLayout;

import javax.swing.*;

public class JPanelExample extends JFrame {
    JButton[] buttons;
    JPanel panel1;
    CustomPanel panel2;
    public JPanelExample(){
        super("面板示例");
        Container container = getContentPane();//创建一个内容面板容器
        container.setLayout(new BorderLayout());//设置该窗口布局
        panel1 = new JPanel(new FlowLayout());
        buttons = new JButton[4];
        for(int i=0;i<buttons.length;i++){
            buttons[i] = new JButton("按钮"+(i+1));
            panel1.add(buttons[i]);//添加按钮
            
        }
        panel2 = new CustomPanel();
        container.add(panel1,BorderLayout.NORTH);
        container.add(panel2,BorderLayout.CENTER);
        pack();
        setVisible(true);
        
        
    }
    

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        JPanelExample jpe=new JPanelExample();
        jpe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }
public class CustomPanel extends JPanel{
    public void paintComponent(Graphics g){
        super.paintComponent(g);
        g.drawString("welcome to java shape world", 20, 20);
        
        g.drawRect(20, 40, 130, 130);//画矩形
        g.setColor(Color.green);
        g.fillRect(20,40,130,130);
        
        g.drawOval(160, 40, 100, 100);//画椭圆型
        g.setColor(Color.orange);
        g.fillOval(160, 40, 100, 100);
        
    }
    public Dimension getPreferredSize(){
        return new Dimension(200,200);
        
    }

    


}

运行结果：

 

 2.基于JFrame实现的窗口界面，窗口界面中间有一个按钮组件。

代码：

import java.awt.*;

import javax.swing.*;

public class JFrameDemo {
    JFrame f;
    JButton b;
    Container c;
    public JFrameDemo(){
        f = new JFrame("JFrame Demo");
        b = new JButton("Press me");
        c=f.getContentPane();//获取内容面板容器
        c.add(b);//为内容面板容器添加按钮组件
        f.setSize(200,200);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        new JFrameDemo();
        

    }

}

运行结果：

 

 其实以上这些都是一些基础知识，从下次开始就会稍稍复杂一点。