e568. determining when a frame or window is opened or closed.txt

来自「这里面包含了一百多个JAVA源文件」· 文本 代码 · 共 27 行

// Create the frame
    Frame frame = new Frame();
    
    // Create a listener for window events
    WindowListener listener = new WindowAdapter() {
        // This method is called after a window has been opened
        public void windowOpened(WindowEvent evt) {
            Frame frame = (Frame)evt.getSource();
        }
    
        // This method is called when the user clicks the close button
        public void windowClosing(WindowEvent evt) {
            Frame frame = (Frame)evt.getSource();
    
            // By default, nothing happens when the user clicks the close button.
            // To close the frame, see e565 Hiding a Frame When Its Close Button Is Clicked
        }
    
        // This method is called after a window is closed
        public void windowClosed(WindowEvent evt) {
            Frame frame = (Frame)evt.getSource();
        }
    };
    
    // Register the listener with the frame
    frame.addWindowListener(listener);