I trying to make a math quiz game that generates random question and keep track of of what question are wrong and write.
I trying to figure out how to make my program respond if the answer written in the text field is correct or incorrect when I click the JButton `answerbutton`. I'm very new to using `ActionListener`.
import java.util.Scanner;
import javax.swing.*;
import javax.swing.border.TitledBorder;
import java.util.Random;
import java.util.Scanner;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class PracticeMath extends JFrame {
Scanner k = new Scanner(System.in);
Random generator = new Random();
protected JButton excerciseButton = new JButton( "New Excerices" ); // start new quiz session
protected JButton answerButton = new JButton( "Answer" ); // set new question, check if the answer correct or wrong
protected JLabel titlelabel = new JLabel( "How much is: " );
protected int correctcounter = 0; // keep track of correct answer
protected int wrongcounter = 0; // keep track of wrong answer
protected int one = generator.nextInt(10);//generate ranodm first number of question
protected int two = generator.nextInt(10); // generate random second number of question
protected int i = generator.nextInt(4); // generate random operator
protected char[] ops = { '+', '-', '/', '*' }; // the math operator
protected JLabel correctlabel = new JLabel(" Number of Correct Answer: ");
protected JLabel wronglabel = new JLabel( " Number of Wrong answers: " );
protected JLabel firstnum = new JLabel("" + one); // display first number
protected JLabel secondnum = new JLabel("" + two); // display second number
protected JLabel randomOP = new JLabel("" + ops[i]); display operator
protected JLabel equalOP = new JLabel("=");
protected JTextField answerText = new JTextField(); //text area for writing you answer
protected JLabel questionmark = new JLabel("?");
protected JLabel correct = new JLabel(""+ correctcounter); // display correct answer
protected JLabel wrong = new JLabel(""+ wrongcounter); // display wrong answer
protected JLabel commentlabel = new JLabel(""); // set a comment for how good you doing. optionial
public PracticeMath(){
answerText.setColumns(5);
JPanel Panel1 = new JPanel();// add a panel
FlowLayout flowLayout = (FlowLayout) Panel1.getLayout();// layout for panel
getContentPane().setLayout( new FlowLayout( FlowLayout.LEFT, 5, 5)); // set layout
getContentPane().add(Panel1); // set panel
titlelabel.setForeground(Color.ORANGE);
titlelabel.setFont(new Font("Tahoma", Font.PLAIN, 25));
Panel1.add(titlelabel);
firstnum.setFont(new Font("Tahoma", Font.PLAIN, 20));
Panel1.add(firstnum);
randomOP.setFont(new Font("Tahoma", Font.PLAIN, 25));
Panel1.add(randomOP);
secondnum.setFont(new Font("Tahoma", Font.PLAIN, 20));
Panel1.add(secondnum);
equalOP.setFont(new Font("Tahoma", Font.PLAIN, 20));
Panel1.add(equalOP);
Panel1.add(answerText);
questionmark.setFont(new Font("Tahoma", Font.PLAIN, 20));
Panel1.add(questionmark);
Panel1.add(commentlabel);
JPanel Panel3 = new JPanel();
FlowLayout flowLayout3 = (FlowLayout) Panel3.getLayout();
flowLayout3.setHgap(15);
getContentPane().setLayout( new FlowLayout( FlowLayout.LEFT, 5, 5));
getContentPane().add(Panel3);
Panel3.add(excerciseButton);
Panel3.add(answerButton);
JPanel panel2 = new JPanel();
panel2.setBorder(new TitledBorder("Statistic"));
getContentPane().add(panel2);
panel2.setLayout(new GridLayout(0, 2, 0, 0));
panel2.add(correctlabel);
panel2.add(wronglabel);
correct.setForeground(Color.GREEN);
correct.setFont(new Font("Tahoma", Font.PLAIN, 25));
panel2.add(correct);
wrong.setForeground(Color.RED);
wrong.setFont(new Font("Tahoma", Font.PLAIN, 25));
panel2.add(wrong);
answerButton.addActionListener( this );
}
public static void main(String[] args) {
PracticeMath frame = new PracticeMath();
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,400);
frame.setTitle( "Math Practice");
frame.setVisible(true);
}
public void actionPerformed( ActionEvent ae )
{
String answer = answerText.getText();
int answerint = Integer.parseInt(answer);
if(one + two == answerint){
correctcounter++;
System.out.println("correct");
firstnum.setText("" + generator.nextInt(11));
randomOP.setText("" + ops[generator.nextInt(4)]);
secondnum.setText("" + generator.nextInt(11));
}
else if(one-two == answerint){
correctcounter++;
System.out.println("correct");
firstnum.setText("" + generator.nextInt(11));
randomOP.setText("" + ops[generator.nextInt(4)]);
secondnum.setText("" + generator.nextInt(11));
}
else if(one * two ==answerint){
correctcounter++;
System.out.println("correct");
firstnum.setText("" + generator.nextInt(11));
randomOP.setText("" + ops[generator.nextInt(4)]);
secondnum.setText("" + generator.nextInt(11));
}else if(one/two == answerint){
correctcounter++;
System.out.println("correct");
firstnum.setText("" + generator.nextInt(11));
randomOP.setText("" + ops[generator.nextInt(4)]);
secondnum.setText("" + generator.nextInt(11));
}
else{
wrongcounter++;
System.out.println("wrong");
firstnum.setText("" + generator.nextInt(11));
randomOP.setText("" + ops[generator.nextInt(4)]);
secondnum.setText("" + generator.nextInt(11));
}
}
}
答案 0 :(得分：0)
为了使您的按钮执行某些所需的操作，就像您说的那样，您将需要使用ActionListener。为此，您需要定义一些实现ActionListener接口的类。如果你想要的话，这个类可以是你的PracticeMath类。所以这样做：
public class PracticeMath extends JFrame implements ActionListener
{...}
执行此操作时，您的PracticeMath类将负责为作为ActionListener接口一部分的任何方法指定定义;在这种情况下
public void actionPerformed( ActionEvent ae )
{
// put something intelligent here
}
然后，您需要将此ActionListener添加到您希望其侦听的任何按钮。即
answerButton.addActionListener( this );
使用“this”作为参数，因为ActionListener是您的PracticeMath类。现在，当您按下应答按钮时，将调用您在actionPerformed（...）方法中输入的任何代码。所以你可以在里面评估你的答案。
更新以反映以下评论：
以下是actionPerformed方法的代码。
public void actionPerformed( ActionEvent ae )
{
String answer = answerText.getText();
int answerint = Integer.parseInt(answer);
if(one + two == answerint){
correctcounter++;
System.out.println("correct");
one = generator.nextInt(11);
two = generator.nextInt(11);
// I don't know if you actually store the operator anywhere
operator = ops[generator.nextInt(4)];
firstnum.setText("" + one);
randomOP.setText("" + operator);
secondnum.setText("" + two);
}
else if(one-two == answerint){
// ... and do the same for the other cases too
当然，这并没有解决这样一个事实，即你没有检查是否真正使用了正确的操作符，但这应该可以解决问题，因为每个答案都会被标记为不正确。