java - 追加した String アイテムを ComboBox に保存する

Question

私は Java と Swing が初めてで、私が抱えている問題の解決策を見つけることができませんでした。コンボボックスに項目を追加できる GUI があります。GUI がシャットダウンされた後、追加された項目をコンボボックスに保持し、再起動したときに新しく追加された項目を保持しようとしています。これを行う簡単な方法はありますか？

GUI のコードは次のとおりです。

package GUI1;

import java.awt.BorderLayout;

public class OnurComboBox extends JDialog implements 
ActionListener, ItemListener {

    private final JPanel contentPanel = new JPanel();
    private JComboBox comboBox = null;
    private int comnum;
    public String combo;
//    final String[] theOptions = {
//  "Option 1", "Option 2", 
//        "Option 3", "Option 4", 
//  "Option 5", "Option 6"
//    };
    private JTextField textField;
    private JTextField textField_1;
    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        try {
            OnurComboBox dialog = new OnurComboBox();
            dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
            dialog.setVisible(true);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Create the dialog.
     */
    public OnurComboBox() {



        setTitle("Choose an Option");
        setSize(325, 300);
        setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        setLocationRelativeTo(null);

        JDesktopPane desktopPane = new JDesktopPane();
        getContentPane().add(desktopPane, BorderLayout.CENTER);

        JButton btnOk = new JButton("OK");
        btnOk.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {                
                System.out.println("The item selected is: " + combo);
                System.exit(0);
            }
        });
        btnOk.setBounds(66, 153, 89, 23);
        desktopPane.add(btnOk);

        JButton btnCancel = new JButton("Cancel");
        btnCancel.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        btnCancel.setBounds(165, 153, 89, 23);
        desktopPane.add(btnCancel);

//        final JComboBox comboBox = new JComboBox(theOptions);
        Vector comboBoxItems=new Vector();
        comboBoxItems.add("A");
        comboBoxItems.add("B");
        comboBoxItems.add("C");
        comboBoxItems.add("D");
        comboBoxItems.add("E");
        final DefaultComboBoxModel model = new DefaultComboBoxModel(comboBoxItems);
        final JComboBox comboBox = new JComboBox(model);
        comboBox.setBounds(10, 34, 187, 23);
        comboBox.setSelectedIndex(-1);
        comboBox.addItemListener(this);
        desktopPane.add(comboBox);
        comboBox.addItemListener(new ItemListener(){
          public void itemStateChanged(ItemEvent ie){
          combo = (String)comboBox.getSelectedItem();
          comnum = comboBox.getSelectedIndex();
          textField.setText(combo);
          }
          });

        textField = new JTextField();
        textField.setBounds(10, 228, 187, 23);
        desktopPane.add(textField);
        textField.setColumns(10);

        textField_1 = new JTextField();
        textField_1.setBounds(10, 103, 187, 23);
        desktopPane.add(textField_1);
        textField_1.setColumns(10);

        JTextPane txtpnSelected = new JTextPane();
        txtpnSelected.setEditable(false);
        txtpnSelected.setText("Item Selected:");
        txtpnSelected.setBounds(10, 202, 89, 23);
        desktopPane.add(txtpnSelected);

        JButton btnAdd = new JButton("Add");
        btnAdd.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (!textField_1.getText().equals("")){
                      int a = 0;
                      for(int i = 0; i < comboBox.getItemCount(); i++){
                      if(comboBox.getItemAt(i).equals(textField_1.getText())){
                      a = 1;
                      break;
                      }
                      }
                      if (a == 1)
                     JOptionPane.showMessageDialog(null,"Combobox already has this item.");
                      else
                     comboBox.addItem(textField_1.getText());
                     JOptionPane.showMessageDialog(null,"Item added to Combobox");
                      }
                      else{
                      JOptionPane.showMessageDialog(null,"Please enter text in the Text Box");
                      }
                      }
                      });

        btnAdd.setBounds(207, 103, 92, 23);
        desktopPane.add(btnAdd);

        JTextPane txtpnEnterTheOption = new JTextPane();
        txtpnEnterTheOption.setText("Enter the new option:");
        txtpnEnterTheOption.setEditable(false);
        txtpnEnterTheOption.setBounds(10, 80, 131, 23);
        desktopPane.add(txtpnEnterTheOption);

        JButton btnRemove = new JButton("Remove");
        btnRemove.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (comboBox.getItemCount() > 0){
                    comboBox.removeItemAt(comnum);
                    JOptionPane.showMessageDialog(null,"Item removed");}
                      else
                      JOptionPane.showMessageDialog(null,"Item not available");
            }
        });
        btnRemove.setBounds(207, 34, 92, 23);
        desktopPane.add(btnRemove);

        JTextPane txtpnSelectAnItem = new JTextPane();
        txtpnSelectAnItem.setText("Select an item from the list or add a new option");
        txtpnSelectAnItem.setBounds(10, 3, 289, 20);
        desktopPane.add(txtpnSelectAnItem);
        setVisible(true);


    }

    public void itemStateChanged(ItemEvent e) {

        if (e.getStateChange() == ItemEvent.SELECTED) {
            JComboBox combo = (JComboBox) e.getSource();
//            int index = combo.getSelectedIndex();
//            display.setIcon(new ImageIcon(
//                ClassLoader.getSystemResource(images[index])));
        }

    }

    @Override
    public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub

    }
}

「Alya'a Gamal」の大きな助けを借りて、仕事をする編集済みの作業コード:

package GUI1;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JDesktopPane;
import java.awt.event.ActionEvent;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;

import javax.swing.JTextField;
import javax.swing.JTextPane;

public class OnurComboBox1 extends JDialog implements 
ActionListener, ItemListener {

    private final JPanel contentPanel = new JPanel();
    private JComboBox comboBox = null;
    private int comnum;
    public String combo;
    private JTextField textField;
    private JTextField textField_1;
    static String filePath = "t.txt";/////this text file have 
//    private PrintWriter out;
//    private BufferedReader input;


    /**
     * Launch the application.
     */
    public static void main(String[] args) {

        try {
            OnurComboBox1 dialog = new OnurComboBox1();
            dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
            dialog.setVisible(true);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Create the dialog.
     * @throws IOException 
     */
    public OnurComboBox1() throws IOException {

        BufferedReader input = new BufferedReader(new FileReader(filePath));  

        final PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("t.txt", true)));

        setTitle("Choose an Option");
        setSize(325, 300);
        setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        setLocationRelativeTo(null);

        JDesktopPane desktopPane = new JDesktopPane();
        getContentPane().add(desktopPane, BorderLayout.CENTER);

        JButton btnOk = new JButton("OK");
        btnOk.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {                
                System.out.println("The item selected is: " + combo);
                out.close();/////to close the text file
                System.exit(0);
            }
        });
        btnOk.setBounds(66, 153, 89, 23);
        desktopPane.add(btnOk);

        JButton btnCancel = new JButton("Cancel");
        btnCancel.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        btnCancel.setBounds(165, 153, 89, 23);
        desktopPane.add(btnCancel);

        List<String> strings = new ArrayList<String>();
        try {
            String line = null;
            try {
                while ((line = input.readLine()) != null) {
                    strings.add(line);
                }
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        } finally {
            try {
                input.close();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        }

        String[] lineArray = strings.toArray(new String[]{});
        final DefaultComboBoxModel model = new DefaultComboBoxModel(lineArray);
        final JComboBox comboBox = new JComboBox(model);

        comboBox.setBounds(10, 34, 187, 23);
        comboBox.setSelectedIndex(-1);
        comboBox.addItemListener(this);
        desktopPane.add(comboBox);
        comboBox.addItemListener(new ItemListener(){
          public void itemStateChanged(ItemEvent ie){
          combo = (String)comboBox.getSelectedItem();
          comnum = comboBox.getSelectedIndex();
          textField.setText(combo);
          }
          });

        textField = new JTextField();
        textField.setBounds(10, 228, 187, 23);
        desktopPane.add(textField);
        textField.setColumns(10);

        textField_1 = new JTextField();
        textField_1.setBounds(10, 103, 187, 23);
        desktopPane.add(textField_1);
        textField_1.setColumns(10);

        JTextPane txtpnSelected = new JTextPane();
        txtpnSelected.setEditable(false);
        txtpnSelected.setText("Item Selected:");
        txtpnSelected.setBounds(10, 202, 89, 23);
        desktopPane.add(txtpnSelected);

        JButton btnAdd = new JButton("Add");
        btnAdd.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (!textField_1.getText().equals("")){
                      int a = 0;
                      for(int i = 0; i < comboBox.getItemCount(); i++){
                      if(comboBox.getItemAt(i).equals(textField_1.getText())){
                      a = 1;
                      break;
                      }
                      }
                      if (a == 1)
                     JOptionPane.showMessageDialog(null,"Combobox already has this item.");
                      else
                     comboBox.addItem(textField_1.getText());
                     out.println(textField_1.getText());////this will add the new value in the text file
                     JOptionPane.showMessageDialog(null,"Item added to Combobox");
                      }
                      else{
                      JOptionPane.showMessageDialog(null,"Please enter text in the Text Box");
                      }
                      }
                      });

        btnAdd.setBounds(207, 103, 92, 23);
        desktopPane.add(btnAdd);

        JTextPane txtpnEnterTheOption = new JTextPane();
        txtpnEnterTheOption.setText("Enter the new option:");
        txtpnEnterTheOption.setEditable(false);
        txtpnEnterTheOption.setBounds(10, 80, 131, 23);
        desktopPane.add(txtpnEnterTheOption);

        JButton btnRemove = new JButton("Remove");
        btnRemove.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (comboBox.getItemCount() > 0){
                    comboBox.removeItemAt(comnum);
                    JOptionPane.showMessageDialog(null,"Item removed");}
                      else
                      JOptionPane.showMessageDialog(null,"Item not available");
            }
        });
        btnRemove.setBounds(207, 34, 92, 23);
        desktopPane.add(btnRemove);

        JTextPane txtpnSelectAnItem = new JTextPane();
        txtpnSelectAnItem.setText("Select an item from the list or add a new option");
        txtpnSelectAnItem.setBounds(10, 3, 289, 20);
        desktopPane.add(txtpnSelectAnItem);
        setVisible(true);


    }

    public void itemStateChanged(ItemEvent e) {

        if (e.getStateChange() == ItemEvent.SELECTED) {
            JComboBox combo = (JComboBox) e.getSource();
//            int index = combo.getSelectedIndex();
//            display.setIcon(new ImageIcon(
//                ClassLoader.getSystemResource(images[index])));
        }

    }

    @Override
    public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub

    }
}

score 1 · Accepted Answer

テキストファイルを使用して読み書きできます

String filePath = "t.txt";/////this text file have

1-テキストファイルを作成し、Vectot（A、B、C、D）をそれぞれ1行に分けて書き込みます

2-テキストを読み取るための 2 つの変数を作成します。

BufferedReader input = new BufferedReader(new FileReader(filePath));

ファイルに書き込む 2 番目の値は add になります。

PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("t.txt", true)));

3-このファイルを次のcomboBoxように読み取ります：

 List<String> strings = new ArrayList<String>();
        try {
            String line = null;
            while ((line = input.readLine()) != null) {
                strings.add(line);
            }
        } catch (FileNotFoundException e) {
            System.err.println("Error, file " + filePath + " didn't exist.");
        } finally {
            input.close();
        }

        String[] lineArray = strings.toArray(new String[]{});
        final DefaultComboBoxModel model = new DefaultComboBoxModel(lineArray);
        final JComboBox comboBox = new JComboBox(model);

4- btnAddボタン内 Actionlistner 追加:

out.println(textField_1.getText());////this will add the new value in the text file

5- btnOkボタン内 Actionlistner 追加:

out.close();/////to close the text file

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDesktopPane;
import javax.swing.JDialog;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JTextPane;

class OnurComboBox extends JDialog implements
        ActionListener, ItemListener {

    private final JPanel contentPanel = new JPanel();
    private JComboBox comboBox = null;
    private int comnum;
    public String combo;
//    final String[] theOptions = {
//  "Option 1", "Option 2", 
//        "Option 3", "Option 4", 
//  "Option 5", "Option 6"
//    };
    private JTextField textField;
    private JTextField textField_1;
    String filePath = "t.txt";
     BufferedReader input = new BufferedReader(new FileReader(filePath));
public static PrintWriter out;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    try {
        out = new PrintWriter(new BufferedWriter(new FileWriter("t.txt", true)));
    } catch (Exception e) {
    }

    try {
        OnurComboBox dialog = new OnurComboBox();
        dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        dialog.setVisible(true);
    } catch (Exception e) {
        e.printStackTrace();
    }
}
    /**
     * Create the dialog.
     */
    public OnurComboBox() throws FileNotFoundException, IOException {



        setTitle("Choose an Option");
        setSize(325, 300);
        setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        setLocationRelativeTo(null);

        JDesktopPane desktopPane = new JDesktopPane();
        getContentPane().add(desktopPane, BorderLayout.CENTER);

        JButton btnOk = new JButton("OK");
        btnOk.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                System.out.println("The item selected is: " + combo);

                out.close();


                System.exit(0);
            }
        });
        btnOk.setBounds(66, 153, 89, 23);
        desktopPane.add(btnOk);

        JButton btnCancel = new JButton("Cancel");
        btnCancel.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        btnCancel.setBounds(165, 153, 89, 23);
        desktopPane.add(btnCancel);

//        final JComboBox comboBox = new JComboBox(theOptions);

        List<String> strings = new ArrayList<String>();
        try {
            String line = null;
            while ((line = input.readLine()) != null) {
                strings.add(line);
            }
        } catch (FileNotFoundException e) {
            System.err.println("Error, file " + filePath + " didn't exist.");
        } finally {
            input.close();
        }

        String[] lineArray = strings.toArray(new String[]{});
        final DefaultComboBoxModel model = new DefaultComboBoxModel(lineArray);
        final JComboBox comboBox = new JComboBox(model);
        comboBox.setBounds(10, 34, 187, 23);
        comboBox.setSelectedIndex(-1);
        comboBox.addItemListener(this);
        desktopPane.add(comboBox);
        comboBox.addItemListener(new ItemListener() {

            public void itemStateChanged(ItemEvent ie) {
                combo = (String) comboBox.getSelectedItem();
                comnum = comboBox.getSelectedIndex();
                textField.setText(combo);
            }
        });

        textField = new JTextField();
        textField.setBounds(10, 228, 187, 23);
        desktopPane.add(textField);
        textField.setColumns(10);

        textField_1 = new JTextField();
        textField_1.setBounds(10, 103, 187, 23);
        desktopPane.add(textField_1);
        textField_1.setColumns(10);

        JTextPane txtpnSelected = new JTextPane();
        txtpnSelected.setEditable(false);
        txtpnSelected.setText("Item Selected:");
        txtpnSelected.setBounds(10, 202, 89, 23);
        desktopPane.add(txtpnSelected);

        JButton btnAdd = new JButton("Add");
        btnAdd.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                if (!textField_1.getText().equals("")) {
                    int a = 0;
                    for (int i = 0; i < comboBox.getItemCount(); i++) {
                        if (comboBox.getItemAt(i).equals(textField_1.getText())) {
                            a = 1;
                            break;
                        }
                    }
                    if (a == 1) {
                        JOptionPane.showMessageDialog(null, "Combobox already has this item.");
                    } else {
                        comboBox.addItem(textField_1.getText());
                    }

                    out.println(textField_1.getText());


                    JOptionPane.showMessageDialog(null, "Item added to Combobox");
                } else {
                    JOptionPane.showMessageDialog(null, "Please enter text in the Text Box");
                }
            }
        });

        btnAdd.setBounds(207, 103, 92, 23);
        desktopPane.add(btnAdd);

        JTextPane txtpnEnterTheOption = new JTextPane();
        txtpnEnterTheOption.setText("Enter the new option:");
        txtpnEnterTheOption.setEditable(false);
        txtpnEnterTheOption.setBounds(10, 80, 131, 23);
        desktopPane.add(txtpnEnterTheOption);

        JButton btnRemove = new JButton("Remove");
        btnRemove.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                if (comboBox.getItemCount() > 0) {
                    comboBox.removeItemAt(comnum);
                    JOptionPane.showMessageDialog(null, "Item removed");
                } else {
                    JOptionPane.showMessageDialog(null, "Item not available");
                }
            }
        });
        btnRemove.setBounds(207, 34, 92, 23);
        desktopPane.add(btnRemove);

        JTextPane txtpnSelectAnItem = new JTextPane();
        txtpnSelectAnItem.setText("Select an item from the list or add a new option");
        txtpnSelectAnItem.setBounds(10, 3, 289, 20);
        desktopPane.add(txtpnSelectAnItem);
        setVisible(true);


    }

    public void itemStateChanged(ItemEvent e) {

        if (e.getStateChange() == ItemEvent.SELECTED) {
            JComboBox combo = (JComboBox) e.getSource();
//            int index = combo.getSelectedIndex();
//            display.setIcon(new ImageIcon(
//                ClassLoader.getSystemResource(images[index])));
        }

    }

    @Override
    public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub
    }
}

score 0 · Accepted Answer

おそらく、あなたの場合、それらをファイルに書き込むのが最も簡単です。Commons IOを見て、ファイルの読み書きを簡単にしてください。最良の方法は、ファイルを読み取り、ファイルの内容からデータを取り込み、表示する一種の初期化方法を用意することです。

次に、リストに何かを追加するたびに、それもファイルに書き込みます。それ、またはデータベース、または ComboBox モデルのシリアル化に行くこともできますが、ファイルの読み取り/書き込みが最も簡単な IMO です。

java - 追加した String アイテムを ComboBox に保存する

2 に答える 2

Related

Reference