import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.*;
public class Task1 extends JFrame implements ActionListener {
    private JLabel word;
    private JLabel[] animal;
    private JButton checkbutton;
    private JPanel jp1, jp2,jp3,jp4;
    private JTextField ans;
    private String answer;
    private String coranswer;
    public Task1() {   
    word=new JLabel("How many animals have come to the party?");
    animal=new JLabel[10];
    jp1 = new JPanel();
    jp2 = new JPanel();
    jp3 = new JPanel();
    jp4 = new JPanel();
    ans = new JTextField(2);
    jp1.setLayout(new GridLayout(0,5));
    jp2.setLayout(new BorderLayout());
    jp3.setLayout(new FlowLayout());
    jp4.setLayout(new FlowLayout());
    this.setTitle("Welcome to the Jungle Party!");
    checkbutton=new JButton("Check!");
    jp4.add(checkbutton);
    jp3.add(word);
    jp3.add(ans);
    jp2.add(BorderLayout.CENTER,jp3);
    jp2.add(BorderLayout.SOUTH,jp4);
    jp2.add(BorderLayout.NORTH,jp1);
    this.makepic1();
    this.getContentPane().add(jp2);
    checkbutton.addActionListener(this);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    this.setLocation(100,100);
    this.setSize(1920,1080);
    this.setVisible(true);

    }
    public void actionPerformed(ActionEvent event){
        answer = ans.getText().trim();
        while(!answer.equals("null")) 
        {
            if (answer.equals(coranswer)){
                word.setText("Correct!How many animals are in the party now?");
                this.makepic2();
                return;
            }
            else{word.setText("Wrong!Try again!");}
            return;}
          }
    private void makepic1(){
        for(int i=0;i<10;i++){
            int j=i+1;
            animal[i]=new JLabel(new ImageIcon(getClass().getResource("animal"+j+".png")));
            jp1.add(animal[i]);
            coranswer="10";
        }
    }
    private void makepic2(){
        jp1.removeAll();
        double t =Math.floor(Math.random()*9 + 1);
        int k= (int) t;
        coranswer= String.valueOf(k) ;
        for(int i = 0;i<k;i++)
        { int j = i + 1;
        animal[i]=new JLabel(new ImageIcon(getClass().getResource("animal"+j+".png")));
        jp1.add(animal[i]);
    }
    }


} 

这段程序就是一开始显示10张图，在文本框里输入正确的数字（一开始固定是10）的话就会显示正确，然后随机再显示1-10个图片，错误的话就会告诉你错误让你重新输入，像这样无限循环。

现在有两个BUG，如果前后两次图片数正好随机成相等的话，不管输入多少都会显示错误（看起来是这种感觉）。如果在前一次输入正确的情况下，再次输入正确的话，图片文字都不会换，必须再按一下CHECK，文字显示错误了，图片同时会换（也就是说，必须是文字显示WRONG的情况下，输入正确的结果才能正常运行，如果是文字显示correct的情况下再次正确了，图片不换，必须先wrong了才行。）

用Eclipse多运行几次就知道这俩BUG是什么意思了。