如何将文本输入从一个 JTextField 传递到另一个 class 中的变量？

Question

我正在尝试创建一个学生注册程序，在该程序中，用户在 JTextField 的 JFrame 中输入数据，并将该数据存储到另一个 class 的变量中。包注册；

import java.util.*;
/**
*
* @author Frank
*/
public class AcgRegistration {


public static void main(String[] args) {

    memberDialogBox memberDialogBox = new memberDialogBox();

}

}



    package acgregistration;

    /**
     *
     * @author Frank
     */
    class acgMember {
 private String name;
 private int num;
 private String email;

 public acgMember(String name, int number, String email) {
    this.name = name;
    this.num = number;
    this.email = email;
 }

 public String getName() {
    return name;
 }

 public void setName(String name) {
    this.name = name;
 }

 public int getNum() {
    return num;
 }

 public void setNum(int num) {
     this.num = num;
 }

 public String getEmail() {
    return email;
 }

 public void setEmail(String email) {
    this.email = email;
 }
 }



 package acgregistration;
 import javax.swing.*;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;

 /**
 *
 * @author Frank
 */
 public class memberDialogBox {

 String options[] = {"Student","Faculty/Staff"};
 JComboBox choices = new JComboBox(options);
 JButton b = new JButton("Confirm");
 JLabel l = new JLabel("Select your ACG Status");

 public memberDialogBox(){
  frame();
 }

 public void frame(){

  JFrame f = new JFrame();
  f.setVisible(true);
  f.setSize(210,150);
  f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

  JPanel p = new JPanel();
  p.add(choices);
  p.add(b);
  p.add(l);

  f.add(p);

  b.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){


          String s = choices.getSelectedItem().toString();
          if ("Student".equals(choices.getSelectedItem())){

               studentDialogBox student = new studentDialogBox();
    //This code gives me an error code saying I should call 
   //acgMemberModel


          }
          else{
                 facultyDialogBox faculty= new facultyDialogBox();
              }

        f.dispose();
          }

  });
  }

 }


 package acgregistration;
 import javax.swing.*;
 import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class studentDialogBox { 
private JTextField nameField = new JTextField("", 20);
private JTextField emailField = new JTextField("", 20);
private JTextField numberField = new JTextField("", 20);
private JButton confirmButton = new JButton("Confirm");
private acgMemberModel model;


public studentDialogBox(acgMemberModel model) {
    this.model = model;
    frame();
}



public void frame() {
    JFrame frame = new JFrame();
    frame.setVisible(true);
    frame.setSize(400, 400);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JPanel panel = new JPanel();
    panel.add(nameField);
    panel.add(emailField);
    panel.add(numberField);
    panel.add(confirmButton);
    frame.add(panel);

    confirmButton.addActionListener(new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent e) {
            String name = nameField.getText();
            String number = numberField.getText();
            String email = emailField.getText();
            acgMember member = new acgMember(name, 
   Integer.valueOf(number), email);
            model.addNew(member);
        }
    });

   }
 }

class acgMemberModel {
private List<acgMember> members = new ArrayList<>();

public void addNew(acgMember member) {
    members.add(member);
}

public List<acgMember> getMembers() {
    return Collections.unmodifiableList(members);
}
}

我基本上是在尝试对所有文本字段执行此操作，然后将其保存到 ArrayList 或 Hashmap 中（基本上是最终结果）。我唯一的问题是，我如何将文本字段输入从一个 class 存储到另一个？任何帮助将不胜感激！谢谢！

Answer 1

您是否尝试过创建要在类 public static 之间共享的变量？

Answer 2

只需在每次填充字段并按下按钮时创建新的成员实例，此操作侦听器的结果将被调用，您将从文本字段中获取所有数据并将其传递给新的实例构造函数。每次创建新成员时，将其单独传递给 MemberModel class。

P.S。您需要阅读一些关于 java 语言命名约定的内容，尤其是关于变量的内容，您在将动作侦听器设置为 TextField 而不是 Button 时犯了错误，因为您的变量名称完全没有意义。我重构代码以将所有变量名称更改为人类可读的形式并修复我的解决方案中的错误，因为所有这些约定都没有被使用。

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class Main {

    public static void main(String[] args) {
        MemberModel model = new MemberModel();
        StudentsToOutputListener outputListener
                = new StudentsToOutputListener(model, new FileOutput(new File("path to your default file")));
        Window studentDialog = new StudentDialogBox(model);
        Window facilityDialog = new FacultyDialogBox();
        Window memberDialog = new MemberDialogBox(studentDialog, facilityDialog);
        memberDialog.show();
    }
}

class Member {
    private String name;
    private int number;
    private String email;

    public Member(String name, int number, String email) {
        this.name = name;
        this.number = number;
        this.email = email;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getNumber() {
        return number;
    }

    public void setNumber(int number) {
        this.number = number;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    @Override
    public String toString() {
        return "Member{" +
                "name='" + name + '\'' +
                ", number=" + number +
                ", email='" + email + '\'' +
                '}';
    }
}

interface Window {
    void show();
}

interface Output {
    void output(List<Member> members);
}

interface Listener {
    void update();
}

class MemberDialogBox implements Window {
    private JFrame frame = new JFrame();
    private JComboBox<Window> choiceComboBox = new JComboBox<>();
    private JButton confirmButton = new JButton("Confirm");
    private JLabel selectLabel = new JLabel("Select your ACG Status");

    public MemberDialogBox(Window... windows) {
        for (Window window : windows) {
            choiceComboBox.addItem(window);
        }
        frame();
    }


    public void show() {
        frame.setVisible(true);
    }

    public void frame() {
        frame = new JFrame();
        frame.setSize(210, 150);
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        JPanel panel = new JPanel();
        panel.add(choiceComboBox);
        panel.add(confirmButton);
        panel.add(selectLabel);
        frame.add(panel);

        confirmButton.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                Window window = (Window) choiceComboBox.getSelectedItem();
                window.show();
                frame.dispose();
            }

        });
    }

}

class StudentDialogBox implements Window, Listener, Output {
    private JTextField nameField = new JTextField("", 20);
    private JTextField emailField = new JTextField("", 20);
    private JTextField numberField = new JTextField("", 20);
    private JButton confirmButton = new JButton("Confirm");
    private JButton saveButton = new JButton("Save students to file");
    private JFrame frame;
    private JList<Member> list = new JList<>();
    private MemberModel model;


    public StudentDialogBox(MemberModel model) {
        this.model = model;
        model.addListener(this);
        frame();
    }


    public void show() {
        frame.setVisible(true);
    }


    public void output(List<Member> members) {
        list.setListData(members.toArray(new Member[]{}));
    }


    public void update() {
        model.outputStudentsTo(this);
    }

    public void frame() {
        frame = new JFrame();
        frame.setSize(400, 400);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new JPanel();
        panel.add(nameField);
        panel.add(emailField);
        panel.add(numberField);
        panel.add(confirmButton);
        panel.add(list);
        panel.add(saveButton);
        frame.add(panel);

        saveButton.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                JFileChooser fileChooser = new JFileChooser();
                fileChooser.showSaveDialog(frame);
                File selectedFile = fileChooser.getSelectedFile();
                Output output = new FileOutput(selectedFile);
                model.outputStudentsTo(output);
            }
        });

        confirmButton.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                String name = nameField.getText();
                String number = numberField.getText();
                String email = emailField.getText();
                Member member = new Member(name, Integer.valueOf(number), email);
                model.addNewStudent(member);
            }
        });

    }


    public String toString() {
        return "Student";
    }
}

class FacultyDialogBox implements Window {

    public void show() {
        System.out.println("you need to implement FacultyDialogBox " +
                "in similar way than StudentDialog box");
    }


    public String toString() {
        return "Faculty/Stuff";
    }
}


class MemberModel {
    private List<Member> students = new ArrayList<>();
    private List<Member> stuff = new ArrayList<>();
    private List<Listener> listeners = new ArrayList<>();

    public void addListener(Listener listener) {
        listeners.add(listener);
    }

    private void notifyListeners() {
        for (Listener listener : listeners) {
            listener.update();
        }
    }

    public void addNewStudent(Member member) {
        students.add(member);
        notifyListeners();
    }

    public void addNewStuff(Member member) {
        stuff.add(member);
        notifyListeners();
    }

    public void outputStudentsTo(Output output) {
        output.output(Collections.unmodifiableList(students));
    }

    public void outputStuffTo(Output output) {
        output.output(Collections.unmodifiableList(stuff));
    }
}

class FileOutput implements Output {
    private final File destination;

    public FileOutput(File destination) {
        this.destination = destination;
    }

    public void output(List<Member> members) {
        try (BufferedWriter file = new BufferedWriter(new FileWriter(destination))) {
            for (Member member : members) {
                file.write(member.toString());
                file.write("\n");
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

}

class StudentsToOutputListener implements Listener {
    private final MemberModel model;
    private final Output output;

    public StudentsToOutputListener(MemberModel model, Output output) {
        this.model = model;
        this.output = output;
        model.addListener(this);
    }

    public void update() {
        model.outputStudentsTo(output);
    }
}

我更新了对你问题澄清的回答，我明白你想实现什么并修复你的程序，我还重构了这段代码并使其更符合 oop 风格和更具可读性，但你需要自己实现其次与学生对话框类似的对话框工具。您还需要将此源中的每个 class 放置到不同的 *.java 文件中。

Answer 3

你说的是数据绑定。我最近发布了一个演示，展示了如何做你需要做的作为这个问题的答案：Switching JPanels moves content diagonally

本质上，GUI 通过事件将信息传递给模型，反之亦然，通常是属性更改事件，但您可以选择很多选项。该过程如下所示：

用户在字段中输入一个值
字段在失去焦点时为属性 "value" 触发属性更改事件
GUI（或控制器 class）侦听属性更改事件并触发另一个事件，例如 Vetoable 更改事件。
模型（或控制器）侦听 Vetoable 更改并验证值，将 "state" 保存在正确的位置。如果验证失败，它会引发异常。
GUI 检查否决异常并在需要时恢复该字段。

类似的方法可以允许模型向 GUI 发送属性更改请求以更新字段的值。

使用这些事件的好处是它使 GUI 保持简单，将模型与表示分离，并使 replace/duplicate 使用另一种技术的 GUI 更容易。

如何将文本输入从一个 JTextField 传递到另一个 class 中的变量？

How do I pass text input from one JTextField to a variable in another class?

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oop

jtextfield