如何使用来自不同 JFrame 的按钮编辑来自另一个 JFrame 的组件？

Question

我一直在尝试制作一个功能，其中用户按下 JFrame 中的按钮。按下按钮后，另一个 JFrame 中的所有文本字段、禁用按钮将重置，（文本字段为空，按钮已启用）但我遇到了一个错误，即我的代码不执行任何操作，或者无法访问另一个类的文本字段和按钮

主类：

public static void main(String[] args) {
   UserInterface userinterface = new UserInterface();
   userinterface.frame_main.setVisible(true); 
}

第一帧：

public class UserInterface{
public JFrame frame_main = new JFrame();
JPanel pnl_main = new JPanel();

JLabel lbl_firstname = new JLabel("First Name: ");
JLabel lbl_lastname = new JLabel("Last Name: ");
JLabel lbl_midname = new JLabel("Middle Name: ");
JLabel lbl_customerno = new JLabel("Contact Number: ");
JLabel lbl_customeremail = new JLabel("Email Address: ");

JButton btn_submit = new JButton("Submit");
JButton btn_clear = new JButton("Clear All");

JTextField txt_firstname = new JTextField(15);
JTextField txt_lastname = new JTextField(15);
JTextField txt_midname = new JTextField(15);
JTextField txt_customerno = new JTextField(13);
JTextField txt_customeremail = new JTextField(15);

 
FlowLayout fl = new FlowLayout();
Font set_font = new Font("", Font.BOLD, 14);




public UserInterface(){
    
    frame_main.setSize(300,300);
    frame_main.setLocation(200,200);
    frame_main.setTitle("Event Driven Program");
    frame_main.setResizable(false);
    frame_main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    
   
    
   txt_firstname.setFont(set_font);
    txt_lastname.setFont(set_font);
    txt_midname.setFont(set_font);
    txt_customerno.setFont(set_font);
    txt_customeremail.setFont(set_font);  
            
    pnl_main.add(lbl_firstname);
    pnl_main.add(txt_firstname);
    
    pnl_main.add(lbl_lastname);
    pnl_main.add(txt_lastname);
    
    pnl_main.add(lbl_midname);
    pnl_main.add(txt_midname);
    
    pnl_main.add(lbl_customerno);
    pnl_main.add(txt_customerno);
    
    pnl_main.add(lbl_customeremail);
    pnl_main.add(txt_customeremail);
    
    
    
    btn_submit.addActionListener(new actionButton1());
    btn_submit.setEnabled(true);
    pnl_main.add(btn_submit);
    
    btn_clear.addActionListener(new actionButton2());
    pnl_main.add(btn_clear);
    
    frame_main.add(pnl_main);
    
}

public JButton getButton(){
    return btn_submit;
}

class actionButton1 implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent e){        
    String firstname = txt_firstname.getText();
        String lastname = txt_lastname.getText();
        String midname = txt_midname.getText();
        String customerno = txt_customerno.getText();
        String customeremail = txt_customeremail.getText();
        
       getButton().setEnabled(false);
        
        new CustomerForm(firstname, lastname, midname, customerno, customeremail).setVisible(true);
    }
}

class actionButton2 implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent e){
        txt_firstname.setText("");
        txt_lastname.setText("");
        txt_midname.setText("");
        txt_customerno.setText("");
        txt_customeremail.setText("");
        
        getButton().setEnabled(true);   
    }
}

}

第2帧（按钮问题所在）：

public class CustomerForm extends JFrame{
JPanel pnl_info = new JPanel();
JTextArea output_area = new JTextArea(20, 20);
JFrame frame_info = new JFrame();

Font set_font = new Font("", Font.BOLD, 14);
FlowLayout fl = new FlowLayout();
 
JButton btn_okay = new JButton("Okay");


String firstname;
String lastname;
String midname;
String customerno;
String customeremail;
UserInterface ui = new UserInterface();
  

public CustomerForm(String firstname, String lastname, String midname, String customerno, String customeremail) {
    
    this.setSize(300,600);
    this.setLocation(500,300);
    
    
    output_area.setBackground(Color.LIGHT_GRAY);
    output_area.setEditable(false);
    output_area.setFont(set_font);
    
    btn_okay.addActionListener( new ActionListener() {
        public void actionPerformed(ActionEvent e) {

            CustomerForm.this.dispose();
            ui.btn_submit.setEnabled(true);
            
            ui.txt_firstname.setText("");
            ui.txt_lastname.setText("");
            ui.txt_midname.setText("");
            ui.txt_customerno.setText("");
            ui.txt_customeremail.setText("");
        }
    });
    
    
    pnl_info.add(output_area);
    pnl_info.add(btn_okay);
    
    
    this.firstname = firstname;
    this.lastname = lastname;
    this.midname = midname;
    this.customerno = customerno;
    this.customeremail = customeremail;
    
    
    output_area.append("\nFirst Name: " + firstname +
                           "\n\nLast Name: " + lastname +
                           "\n\nMiddle Name: " + midname +
                           "\n\nContact Number: " + customerno +
                           "\n\nEmail Address: " + customeremail);
    
    this.add(pnl_info, BorderLayout.CENTER);
    
}



}

我认为问题在于我参考了第一帧，但我还不知道是什么导致了真正的问题希望有人可以帮助我，这将是我学习 Java 的一大推动力。

Answer 1

首先：类名通常以大写开头。 您正在尝试从不是 GUI 线程的 actionPerformed 方法操作 GUI。看看这个： How to pass the message from working thread to GUI in java