给我的第一篇文章。我是计算机科学学位第一年的学生。
我只是为分配构建一个基本的 GUI，由于某种原因，我一生都看不到，这是我创建的 JFrame 之一，当从注册按钮调用注册类的实例时，它显示完全空白登录类中的动作侦听器...
我还有一个单独的主类，其中包含 Main 方法并调用 Login 类。登录类 JFrame 工作正常，如前所述，只有在登录类的注册按钮操作侦听器中调用注册类时，才会出现问题。程序中的所有其他 JFrame 也可以正常工作。
我试图直接从 main 调用 Register 类，它也有同样的问题，尽管我试图将其简化为最基本的形式，但除了空白的无色 JFrame 之外，它仍然不显示任何内容。
这是代码（未完成但按原样工作）。我为我的草率道歉，但我是一个完整的初学者。
谁能看到它有什么问题？
提前致谢！
package guitest;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
public class Register extends JFrame{
JButton regSubmit = new JButton("Submit");
JTextField email = new JTextField();
JTextField name = new JTextField();
JTextField Address1 = new JTextField();
JTextField Address2 = new JTextField();
JPasswordField password1 = new JPasswordField();
JPasswordField password2 = new JPasswordField();
String nameTxt = email.getText();
String passTxt = password1.getText();
String info = "";
FlowLayout layout1 = new FlowLayout();
public void Reg(){
this.setTitle("La Volpe Registration");
this.setLayout(layout1);
this.add(Address1);
this.add(Address2);
this.add(email);
this.add(password1);
this.add(password2);
this.add(name);
this.add(regSubmit);
this.getContentPane().setBackground(Color.green);
this.setSize(370, 160);
regSubmit.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
regSubmitActionPerformed(evt);
}
private void regSubmitActionPerformed(java.awt.event.ActionEvent evt) {
String name = email.getText();
String pass = password1.getText();
String info = "";
System.out.println("registering...");
boolean eof;
try{
// Create file
FileWriter file = new FileWriter("\\regdata.txt");
BufferedWriter out = new BufferedWriter(file);
out.write("\n"+nameTxt+", "+passTxt);
}
catch (Exception e){
}
}
});
this.setVisible(true);
}
}
以及链接到它的类...
package guitest;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
/**
* @author david
*/
public class Login {
JFrame loginFrame = new JFrame();
Register reg3 = new Register();
JButton submit = new JButton("Submit");
JButton clear = new JButton("Clear");
JButton register = new JButton ("Register with Us");
JPasswordField pass = new JPasswordField(20);
JTextField email = new JTextField(20);
JLabel em = new JLabel("Email Address: ");
JLabel pw = new JLabel("Password: ");
String pathname;
String line;
String [] records = new String [1000];
int count = 0;
FlowLayout layout1 = new FlowLayout();
public Login(){
//Adds Email label and text field
loginFrame.add(em);
loginFrame.add(email);
//Adds password label and field
loginFrame.add(pw);
loginFrame.add(pass);
//Adds buttons
loginFrame.add(submit);
loginFrame.add(clear);
loginFrame.add(register);
loginFrame.getContentPane().setBackground(Color.green);
loginFrame.setLayout(layout1);
loginFrame.setSize(370, 160);
loginFrame.setTitle("La Volpe - Login");
submit.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
submitActionPerformed(evt);
}
private void submitActionPerformed(java.awt.event.ActionEvent evt){
String emailadd = email.getText();
String password = pass.getText();
pathname = "\\regdata.txt";
boolean eof;
try{
FileReader file = new FileReader(pathname);
BufferedReader buff = new BufferedReader(file);
eof = false; // set the eof boolean to false
while (!eof){
line = buff.readLine();
if (line == null){ // test to see if the end of file has been reached
eof = true; // if the end of file has been found set the eof Boolean to true
}
else{
// end of file not reached so move the contents of the line to the records
//array
records[count] = line;
count ++;
System.out.println(line); // print out the new line input for error checking
}
}
buff.close();
}
catch (IOException e){
System.out.println("Error -- "+ e.toString());
}
boolean notTrue = false;
for (int i = 0; i < count; i++) {
if ((!notTrue)&&((emailadd + "," + password).equals(records[i]))) {
FoodSelectionMain loggedIn = new FoodSelectionMain();
loggedIn.setVisible(true);
}
}
if (!notTrue){
JOptionPane.showInputDialog("Please check your login "
+ "and try again. If you are a new user, please "
+ "register by pressing the 'REGISTER' button");
}
}
});
// TODO add your handling code here:
clear.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
clearActionPerformed(evt);
}
public void clearActionPerformed(java.awt.event.ActionEvent evt){
email.setText(null);
pass.setText(null);
}
});
register.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
registerActionPerformed(evt);
}
public void registerActionPerformed(java.awt.event.ActionEvent evt){
reg3.setVisible(true);
System.out.println("Register pressed");
}
});
loginFrame.setVisible(true);
}
}