带有预览的自定义对话框

Question

对于我当前的项目，我需要一个自定义对话框，允许用户选择一个值并获得其详细信息的自定义预览。我尝试编写自己的扩展 JFrame 的窗口类，但直到现在我都停留在最重要的部分：如何显示对话框的窗口，让用户进行输入然后返回选定的值？

我尝试查看JOptionPane.showInputDialog 的代码，但我感到困惑，而不是理解它是如何工作的。

这是我的问题的sscce：

import java.util.Vector;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JTextArea;

public class MyCustomDialog extends JFrame {
    JComboBox<MyCustomObject> comboBox;
    JTextArea details;

    public MyCustomDialog(Vector<MyCustomObject> data) {
        comboBox = new JComboBox<>(data);
        comboBox.setSelectedIndex(-1);
        comboBox.setEditable(false);
        comboBox.addActionListener(ActionEvent -> updateDetails());
        getContentPane().add(comboBox);

        details = new JTextArea();
        details.setEditable(false);
        details.setOpaque(false);
        getContentPane().add(details);

        setVisible(true);
    }

    void updateDetails() {
        int selectedIndex = comboBox.getSelectedIndex();
        if(selectedIndex < 0) {
            details.setText("");
            return;
        }

        MyCustomObject selected = comboBox.getItemAt(selectedIndex);
        details.setText(selected.getDescription());
    }

    static MyCustomObject showDialog(Vector<MyCustomObject> vec) {
        // this is where I'm stuck

        // showDialog needs to:
        // 1. create the frame and show it to the user
        // 2. let the user choose a value and also change their selection multiple times
        // 3. let the user confirm the selection, for example with a button
        // 4. return the selected value

        return null;
    }

    public static void main(String... args) {
        Vector<MyCustomObject> vec = new Vector<>();
        vec.add(new MyCustomObject("Test Object 1", "Test Information 1"));
        vec.add(new MyCustomObject("Test Object 2", "Test Information 2"));
        System.out.println(showDialog(vec) + " was selected.");
    }

    public static class MyCustomObject {
        final String description;
        final String name;

        public MyCustomObject(String name, String description) {
            this.name = name;
            this.description = description;
        }

        String getDescription() { return description; }

        @Override
        public String toString() { return name; }
    }
}

感谢trashgod的回答更新了代码

import java.util.Vector;
import javax.swing.JComboBox;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextArea;

public class MyCustomDialog extends JPanel {
    JComboBox<MyCustomObject> comboBox;
    JTextArea details;

    MyCustomDialog(Vector<MyCustomObject> data) {
        comboBox = new JComboBox<>(data);
        comboBox.setSelectedIndex(-1);
        comboBox.setEditable(false);
        comboBox.addActionListener(ActionEvent -> updateDetails());
        add(comboBox);

        details = new JTextArea();
        details.setEditable(false);
        details.setOpaque(false);
        add(details);
    }

    void updateDetails() {
        int selectedIndex = comboBox.getSelectedIndex();
        if(selectedIndex < 0) {
            details.setText("");
            return;
        }

        MyCustomObject selected = comboBox.getItemAt(selectedIndex);
        details.setText(selected.getDescription());
    }

    static MyCustomObject showDialog(Vector<MyCustomObject> vec) {
        MyCustomDialog dialog = new MyCustomDialog(vec);

        int result = JOptionPane.showConfirmDialog(null, dialog, "Test Dialog", JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
        if (result == JOptionPane.OK_OPTION) {
            int selectedIndex = comboBox.getSelectedIndex();
            if (selectedIndex >= 0) return comboBox.getItemAt(selectedIndex);
        }

        return null;
    }

    public static void main(String... args) {
        Vector<MyCustomObject> vec = new Vector<>();
        vec.add(new MyCustomObject("Test Object 1", "Test Information 1"));
        vec.add(new MyCustomObject("Test Object 2", "Test Information 2"));
        System.out.println(showDialog(vec) + " was selected.");
    }

    public static class MyCustomObject {
        final String description;
        final String name;

        public MyCustomObject(String name, String description) {
            this.name = name;
            this.description = description;
        }

        String getDescription() { return description; }

        @Override
        public String toString() { return name; }
    }
}

Answer 1

如何显示对话框的窗口，让用户进行输入然后返回选定的值？

通常的做法是使用modal dialog； JOptionPane，见 here，是处理这种用法的便捷方式。更多示例请见here。

除了使用JOptionPane之外别无选择？

您可以使用JDialog，带或不带JOptionPane，分别如here 和here 所示。