3

我在任何地方都找不到任何工作，并且代码似乎与您在 Applet 中的操作方式不同，我已经习惯了。我是摇摆新手。如何向我的 JButtons 添加一个 ActionListener（是吗？还是我在寻找其他东西？）？（我不确定是什么导致code块像那样不稳定，我无法修复它。）

` 

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

public class Main implements ActionListener{

static String answerOne = "";
static String answerTwo = "";
static boolean answerable = false;
static int labelX = 240, labelY = 48;
static int questionWrite = 0;
static String text = "Welcome! I will ask simple, two-answer questions, and you will answer them. Simple as that. ";
static int charIndex = 0;

private static void createAndShowGUI() {
    JFrame frame = new JFrame("FrameDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JLabel emptyLabel = new JLabel("");
    emptyLabel.setPreferredSize(new Dimension(300, 225));
    frame.getContentPane().add(emptyLabel, BorderLayout.CENTER);

    frame.pack();
    frame.setVisible(true);

    frame.setLayout(null);
    frame.setResizable(false);

    JPanel buttons = new JPanel(new FlowLayout());
    final JButton buttonOne = new JButton(answerOne);
    final JButton buttonTwo = new JButton(answerTwo);
    final JButton buttonThree = new JButton("Continue");
    buttonThree.setActionCommand("continue");

    if (answerable == true) {
    buttons.add(buttonOne);
    buttons.add(buttonTwo);
    } else {
        buttons.add(buttonThree);
    }

    frame.add(buttons);

    final JLabel centerText = new JLabel("<html>");
    frame.add(centerText);

    buttons.reshape(50, 185, 200, 40);
    centerText.reshape(10, 10, 280, 160);

    Timer timer = new Timer(50, new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
        String labelText = centerText.getText();
        labelText += text.charAt(charIndex);
        centerText.setText(labelText);
        charIndex++;
        if (charIndex >= text.length()) {
            ((Timer)e.getSource()).stop();
        }

        Object buttonClicked = e.getSource();
        if(buttonClicked == buttonOne) {
            System.out.println("One.");
        }
        else if(buttonClicked == buttonTwo) {
            System.out.println("Two.");
        }
        else if(buttonClicked == buttonThree) {
            System.out.println("Continuing.");
        }

        //writeNext(Text to write, button one text, button two text, yes/no or "continue"); 
        switch(questionWrite) {
        case 0:
            writeNext("Welcome! I will ask simple, two-answer questions, and you will answer them. Simple as that. ", null, null, false);
            break;
        case 1:
            writeNext("Is Canada the largest country?", "Yes", "No,", true);
            break;
        case 2:
            writeNext("Have humans been to Mars?", "Yes", "No", true);
            break;
        }
    }

});

    timer.start();
}

public static void main(String[] args) {
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });



}
public static void writeNext(String textM, String answerOneM, String answerTwoM, boolean answerableM) {
        text = textM;
        answerOne = answerOneM;
        answerTwo = answerTwoM;
        answerable = answerableM;
    }

@Override
public void actionPerformed(ActionEvent arg0) {

}

}`

4

1 回答 1

5 
button.addActionListener(new ActionListener()
{
    public void actionPerformed(ActionEvent e)
    {
        //action listener here
    }
});

由于您必须将对象传递给addActionListener，因此您不能从静态上下文中执行此操作。因此，您创建了一个匿名类的实例并将其与您的操作事件处理程序一起传递。

或者，您可以在您的类中编写该actionPerformed方法。不过，最好给它一个构造函数来识别它。

private int button;
public Main(int button)
{
    this.button = button;
}

然后添加动作监听器：

button.addActionListener(new Main(1)); //or pass it 2, 3, 4 ... just some unique integer

在您的 actionPerformed 中，您可以读取传入的整数。

if(this.button==1)
{
    //do button 1 stuff
}
于 2013-09-19T19:57:11.363 回答