將單獨的JPanel / JInternalFrame加載到單獨的JDesktopPane（在JFrame中）

Question

假設我有一個NewMDIApplication extends javax.swing.JFrame的類，其中包含JDesktopPane和JButton 。 還要假設我還有另一個類NewJInternalFrame extends javax.swing.JInternalFrame或NewJPanel extends javax.swing.JPanel ， NewJPanel extends javax.swing.JPanel包含一些用於執行某些操作的“按鈕”和“文本框”。

我的意圖是當我單擊JButton時，將NewMDIApplication的對象或NewJPanel的對象加載到NewJInternalFrame的JDesktopPane中。 有可能做到嗎？ 如果是，該怎么做？

Answer 1

這是將JInternalFrame實例添加到JDesktopPane的工作示例。 請注意，您需要設置大小，否則它們不會出現。

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.EmptyBorder;

public class FrameWithInternalFrames {

    public static void main(String[] args) {
        Runnable r = new Runnable() {

        @Override
        public void run() {
            // the GUI as seen by the user (without frame)
            JPanel gui = new JPanel(new BorderLayout());
            gui.setBorder(new EmptyBorder(2, 3, 2, 3));

            gui.setPreferredSize(new Dimension(400, 100));
            gui.setBackground(Color.WHITE);

            final JDesktopPane dtp = new JDesktopPane();
            gui.add(dtp, BorderLayout.CENTER);

            JButton newFrame = new JButton("Add Frame");

            ActionListener listener = new ActionListener() {
            private int disp = 10;
            @Override
            public void actionPerformed(ActionEvent e) {
                JInternalFrame jif = new JInternalFrame();
                dtp.add(jif);
                jif.setLocation(disp, disp);
                jif.setSize(100,100); // VERY important!
                disp += 10;
                jif.setVisible(true);
            }
            };
            newFrame.addActionListener(listener);

            gui.add(newFrame, BorderLayout.PAGE_START);

            JFrame f = new JFrame("Demo");
            f.add(gui);
            // Ensures JVM closes after frame(s) closed and
            // all non-daemon threads are finished
            f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
            // See http://stackoverflow.com/a/7143398/418556 for demo.
            f.setLocationByPlatform(true);

            // ensures the frame is the minimum size it needs to be
            // in order display the components within it
            f.pack();
            // should be done last, to avoid flickering, moving,
            // resizing artifacts.
            f.setVisible(true);
        }
        };
        // Swing GUIs should be created and updated on the EDT
        // http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
        SwingUtilities.invokeLater(r);
    }
}