java - 将视频帧添加到 JTabbedpane

Question

我创建了一个 Java 选项卡式 Pane 。在选项卡式 Pane 中，我创建了一个名为“视频”的选项卡。我希望每当我单击视频选项卡时，视频都会自动在选项卡面板本身上播放。我可以这样做吗？如果是，请告诉我该怎么做。

Answer 1

您必须将 ChangeListener 添加到 JTabbedPane 组件并重写 stateChanged 方法:

    tabbedPane.addChangeListener(new ChangeListener() {

        @Override
        public void stateChanged(ChangeEvent e) {
            if (e.getSource() instanceof JTabbedPane) {
                JTabbedPane pane = (JTabbedPane) e.getSource();
                if (pane.getSelectedIndex() == 2) {

                    // start playing the media clip in tab 2
                    mediaPlayer.start(); 

                }
            }
        }
    });

这是一个完整的工作代码:

package tabvideo;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.media.CannotRealizeException;
import javax.media.NoPlayerException;
import javax.media.Player;
import javax.media.Manager;

public class TabbedPaneVideoDemo extends JPanel {

    Player mediaPlayer = null;

    public TabbedPaneVideoDemo() {
        super(new GridLayout(1, 1));

        JTabbedPane tabbedPane = new JTabbedPane();
        ImageIcon icon = createImageIcon("images/icon.gif");

        JComponent panel1 = makeTextPanel("Panel #1");
        tabbedPane.addTab("Tab 1", icon, panel1, "Does nothing");
        tabbedPane.setMnemonicAt(0, KeyEvent.VK_1);

        JComponent panel2 = makeTextPanel("Panel #2");
        tabbedPane.addTab("Tab 2", icon, panel2, "Does twice as much nothing");
        tabbedPane.setMnemonicAt(1, KeyEvent.VK_2);

        JComponent panel3 = makeTextPanel("Panel #3");
        tabbedPane.addTab("Tab 3", icon, panel3, "Still does nothing");
        tabbedPane.setMnemonicAt(2, KeyEvent.VK_3);

        JComponent panel4 = makeVideoPanel("somevideo.avi");
        tabbedPane.addTab("Tab 4", icon, panel4, "Playes video!");
        tabbedPane.setMnemonicAt(3, KeyEvent.VK_4);

        tabbedPane.addChangeListener(new ChangeListener() {

            @Override
            public void stateChanged(ChangeEvent e) {
                if (e.getSource() instanceof JTabbedPane) {
                    JTabbedPane pane = (JTabbedPane) e.getSource();
                    if (pane.getSelectedIndex() == 2) {

                        // start playing the media clip in tab 2
                        mediaPlayer.start();

                    }
                }
            }
        });

        // Add the tabbed pane to this panel.
        add(tabbedPane);

        // The following line enables to use scrolling tabs.
        tabbedPane.setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
    }

    protected JPanel makeVideoPanel(String filename) {
        JPanel panel = new JPanel(false);

        panel.setLayout(new BorderLayout()); // use a BorderLayout

        // Use lightweight components for Swing compatibility
        Manager.setHint(Manager.LIGHTWEIGHT_RENDERER, true);

        try {

            URL mediaURL = new File(filename).toURI().toURL();

            // create a player to play the media specified in the URL
            mediaPlayer = Manager.createRealizedPlayer(mediaURL);

            // get the components for the video and the playback controls
            Component video = mediaPlayer.getVisualComponent();
            Component controls = mediaPlayer.getControlPanelComponent();

            if (video != null)
                panel.add(video, BorderLayout.CENTER); // add video component

            if (controls != null)
                panel.add(controls, BorderLayout.SOUTH); // add controls

        } // end try
        catch (NoPlayerException noPlayerException) {
            System.err.println("No media player found");
        } // end catch
        catch (CannotRealizeException cannotRealizeException) {
            System.err.println("Could not realize media player");
        } // end catch
        catch (IOException iOException) {
            System.err.println("Error reading from the source");
        } // end catch

        return panel;
    } // end MediaPanel constructor

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path) {
        java.net.URL imgURL = TabbedPaneVideoDemo.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    protected JComponent makeTextPanel(String text) {
        JPanel panel = new JPanel(false);
        JLabel filler = new JLabel(text);
        filler.setHorizontalAlignment(JLabel.CENTER);
        panel.setLayout(new GridLayout(1, 1));
        panel.add(filler);
        return panel;
    }

    /**
     * Create the GUI and show it. For thread safety, this method should be
     * invoked from the event dispatch thread.
     */
    private static void createAndShowGUI() {
        // Create and set up the window.
        JFrame frame = new JFrame("TabbedPaneDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Add content to the window.
        frame.add(new TabbedPaneVideoDemo(), BorderLayout.CENTER);

        // Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        // Schedule a job for the event dispatch thread:
        // creating and showing this application's GUI.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                // Turn off metal's use of bold fonts
                UIManager.put("swing.boldMetal", Boolean.FALSE);
                createAndShowGUI();
            }
        });
    }

}