Question

我希望能够检测到JInternalFrame中JDesktopPane的所有实例何时关闭。我一直在查看桌面窗格触发的事件，但我看不到适用的事件。我已经尝试为添加到桌面窗格的每个人添加JInternalFrameListener并收听已关闭的活动，但这似乎无效。

Answer 1

这是一个工作示例：

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

public class InternalFrameDemo extends JFrame {
    JDesktopPane desktop;
    InternalFrameAdapter adapter;
    int frameCount = 0;

    public InternalFrameDemo() {
        super("InternalFrameDemo");

        adapter = new InternalFrameAdapter() {
            public void internalFrameClosed(InternalFrameEvent e) {
                frameCount--;
                if (frameCount == 0) {
                    JOptionPane.showMessageDialog(InternalFrameDemo.this, "All internal frames closed.");
                }
            }
        };

        setExtendedState(getExtendedState() | JFrame.MAXIMIZED_BOTH);

        desktop = new JDesktopPane();
        createFrame();
        createFrame();
        createFrame();
        setContentPane(desktop);
    }

    protected void createFrame() {
        JInternalFrame frame = new JInternalFrame("title", true, true);
        frame.setSize(300,300);
        frame.setVisible(true);
        frame.setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
        frameCount++;
        frame.addInternalFrameListener(adapter);
        desktop.add(frame);
    }

    private static void createAndShowGUI() {
        InternalFrameDemo frame = new InternalFrameDemo();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } 
        catch (UnsupportedLookAndFeelException e) {
           // handle exception
        }
        catch (ClassNotFoundException e) {
           // handle exception
        }
        catch (InstantiationException e) {
           // handle exception
        }
        catch (IllegalAccessException e) {
           // handle exception
        }
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

你基本上在每个内部框架上添加一个监听器，并跟踪打开和关闭的框架（使用int变量）。

如何检测桌面窗格中所有内部框架何时关闭？

1 个答案: