相关疑难解决方法(0)

我试图将一个Graphics对象添加/绘制到现有的JPanel.我正在生成10个随机大小的初始Graphics对象并放置在面板中,但是想要一次添加额外的绘制对象,随机调整大小并放置像初始10.

目前,AddNewDrawItem类不呈现新的Graphics对象.

谢谢你的意见.

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;

public class Painter{

private DrawingPanel dp = new DrawingPanel();

    //constructor
    public Painter(){
        buildGUI();
    }

    private void buildGUI(){
        JFrame frame = new JFrame();
        frame.setLayout(new BorderLayout());
        frame.setTitle("Paint drawing demonstration");
        JPanel headerPanel = new JPanel();
        headerPanel.add(new JLabel("The drawing panel is below"));
        JButton addNew = new JButton("Add New Graphic");
        addNew.addActionListener(new addNewClickHandler());
        headerPanel.add(addNew);            
        frame.add(BorderLayout.NORTH,headerPanel);
        frame.add(BorderLayout.SOUTH,this.dp);  
        frame.pack();
        frame.setVisible(true);
    }

    class DrawingPanel extends JPanel {

        public void paintComponent(Graphics g) {
            super.paintComponent(g);       
            this.setBackground(Color.white);

            int x, …