JComboBox 与 JButton 进入 TextField

Question

我想检测单击JButton 时选择了哪些JComboBox 项目。结果将放在我在执行的操作中堆积的TextField 中。

例如，当我选择一个合适的数字时，它将使用 JButton 分类，结果将显示在 TextField 上。

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class mFrame extends JFrame implements ActionListener
{
JLabel lblAge = new JLabel("Age");
JComboBox cboAge = new JComboBox();
JButton btnClass = new JButton("Classification");
JTextField txtField = new JTextField();
JButton btnClose = new JButton("Close");

public mFrame()
{
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setLayout(null);
    setSize(400,200);

    add(lblAge);
    add(cboAge);
    add(btnClass);
    add(txtField);
    add(btnClose);

    lblAge.setBounds(10,10,100,20);
    cboAge.setBounds(140,10,120,20);
    btnClass.setBounds(10,30,120,20);
    txtField.setBounds(140,30,120,20);
    btnClose.setBounds(200,105,70,20);
    for (int j = 10; j < 101; j++) cboAge.addItem(new Integer(j));

    cboAge.addActionListener(this);
    btnClass.addActionListener(this);
    txtField.addActionListener(this);
    btnClose.addActionListener(this);
    setVisible(true);
}
public void actionPerformed(ActionEvent age)
{
    //if (age.getSource() == btnClass)
    {
        //
    if (age.getSource() == btnClose)
    {
        System.exit(0);
    }
}
}
}
  class StartHere
{
    public static void main(String [] args)
    {
        new mFrame();
    }
}

Answer 1

首先，对于 txtField 和 cboAge，您不需要 addActionListener() 因为在那里执行操作时您没有做任何事情。 只为按钮做。

这就是actionPerformed() 的样子（注意：我将ActionEvent age 更改为ActionEvent e）

public void actionPerformed(ActionEvent e){
    if (e.getSource() == btnClass){
        String selectedValue = cboAge.getSelectedItem().toString();

        // if you need it as integer...
        int age = Integer.parseInt(selectedValue);

        // do your classification processing... assuming output value is assigned in String result.

        //ex for classification processing:
        String result = "";
        if(age>=10 && age<=19){
              result = "Teenage";
        }else if(age>=20 && age<=28){
              result = "blah blah";
        }//... and so on...

        txtField.setText(result);
    }else if (e.getSource() == btnClose){
        System.exit(0);
    }
}