java - JSlider 在 10 秒后隐藏，就像在电视机中一样

Question

我制作了一个程序，其中左右箭头显示 JSlider 上的音量减小，而向上和向下箭头显示正在更改的 channel ，即屏幕上显示不同的颜色。我希望只要屏幕稳定 10 秒或更长时间，“音量是”和“ channel 是”文本以及 JSlider 就会消失，就像电视机中发生的情况一样。我使用 Java Eclipse 和 VisualSwing 作为我的 GUI。我当前的代码是:

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.Timer;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JSlider;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

import org.dyno.visual.swing.layouts.Constraints;
import org.dyno.visual.swing.layouts.GroupLayout;
import org.dyno.visual.swing.layouts.Leading;


public class TVPanel extends JPanel {

    private static JLabel vollab;
    private int ChannelNo;
    private static final long serialVersionUID = 1L;
    private JLabel jLabel0;
    private int VolumeMax=10;
    private JButton jButton0;
    private JSlider jSlider0;
    private JMenuItem jMenuItem0;
    private JPopupMenu jPopupMenu0;
    private JLabel jLabel1;
    private static final String PREFERRED_LOOK_AND_FEEL = "javax.swing.plaf.metal.MetalLookAndFeel";
    public TVPanel() { 
        ChannelNo=0;
        initComponents();
    }

    private void initComponents() {
        setLayout(new GroupLayout());
        add(getJButton0(), new Constraints(new Leading(100, 176, 10, 10), new Leading(39, 72, 10, 10)));
        add(getJSlider0(), new Constraints(new Leading(46, 10, 10), new Leading(162, 10, 10)));
        add(getJLabel1(), new Constraints(new Leading(111, 10, 10), new Leading(129, 12, 12)));
        add(getJLabel0(), new Constraints(new Leading(37, 68, 12, 12), new Leading(129, 12, 12)));
        addKeyListener(new KeyAdapter() {

            public void keyTyped(KeyEvent event) {
                keyKeyTyped(event);
            }

            public void keyPressed(KeyEvent event) {
                keyKeyPressed(event);
            }
        });
        addMouseListener(new MouseAdapter() {

            public void mouseClicked(MouseEvent event) {
                mouseMouseClicked(event);
            }
        });
        setSize(478, 240);
    }

    private JLabel getJLabel1() {
        if (jLabel1 == null) {
            jLabel1 = new JLabel();
            jLabel1.setText("10");
        }
        return jLabel1;
    }

    private JSlider getJSlider0() {
        if (jSlider0 == null) {
            jSlider0 = new JSlider();
            jSlider0.setMajorTickSpacing(1);
            jSlider0.setMaximum(10);
            jSlider0.setPaintLabels(true);
            jSlider0.setPaintTicks(true);
            jSlider0.setValue(10);
            jSlider0.setAlignmentX(1.0f);
            jSlider0.setInheritsPopupMenu(true);
            jSlider0.setValueIsAdjusting(true);
        }
        return jSlider0;
    }

    private JButton getJButton0() {
        if (jButton0 == null) {
            jButton0 = new JButton();
            jButton0.setText("");
            jButton0.setSize(150, 150);
        }
        return jButton0;
    }

    private JLabel getJLabel0() {
        if (jLabel0 == null) {
            jLabel0 = new JLabel();
            jLabel0.setText("Volume Is");
        }
        return jLabel0;
    }
    private static void installLnF() {
        try {
            String lnfClassname = PREFERRED_LOOK_AND_FEEL;
            if (lnfClassname == null)
                lnfClassname = UIManager.getCrossPlatformLookAndFeelClassName();
            UIManager.setLookAndFeel(lnfClassname);
        } catch (Exception e) {
            System.err.println("Cannot install " + PREFERRED_LOOK_AND_FEEL
                    + " on this platform:" + e.getMessage());
        }
    }

    /**
     * Main entry of the class.
     * Note: This class is only created so that you can easily preview the result at runtime.
     * It is not expected to be managed by the designer.
     * You can modify it as you like.
     */
    public static void main(String[] args) {
        installLnF();
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                JFrame frame = new JFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setTitle("TVPanel");
                //JLabel volLab= new JLabel();
                vollab= new JLabel("test");
                frame.getContentPane().add(vollab);
                frame.requestFocus();
                frame.isFocusable();
                vollab.isVisible();
                TVPanel content = new TVPanel();
                content.setPreferredSize(content.getSize());
                frame.add(content, BorderLayout.CENTER);
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);

            }
        });
    }

    //Arrows
    private void keyKeyPressed(KeyEvent event) {
        jLabel0.setVisible(true);
        jLabel1.setVisible(true);
        Color colorarr[]= new Color[] {Color.BLACK,Color.WHITE,Color.BLUE,Color.CYAN,Color.RED,Color.GREEN,Color.GRAY,Color.MAGENTA,Color.ORANGE,Color.YELLOW};
        //int Volume=10;
        //int ChannelNo=10;
            //jLabel0.setText(Integer.toString(event.getKeyCode()));


            if(event.getKeyCode()== 37){
                VolumeMax--;
                jSlider0.setValue(VolumeMax);
                jLabel0.setText("Volume Is");
                jLabel1.setText(Integer.toString(jSlider0.getValue()));
            }
            else if(event.getKeyCode()==38)//UP{
            {
                ChannelNo++;
                for(int i=0; i<ChannelNo;i++){
                    if(i<10){
                    jButton0.setBackground(colorarr[i]);
                    jLabel0.setText("Channel Is");
                    jLabel1.setText(Integer.toString(i+1));

                    }
                }
            }
            else if(event.getKeyCode()==39){
                //RIGHT
                VolumeMax++;
                jSlider0.setValue(VolumeMax);
                jLabel1.setText(Integer.toString(jSlider0.getValue()));
            }
            else if(event.getKeyCode()==40){
                ChannelNo--;
                    if(ChannelNo>0){
                jButton0.setBackground(colorarr[ChannelNo-1]);
                jLabel0.setText("Channel Is");
                jLabel1.setText(Integer.toString(ChannelNo-1));
                }
            }

    this.requestFocus();
    }

    private void mouseMouseClicked(MouseEvent event) {
        //jLabel0.setText("mouse");
    this.requestFocus();
    }

    //Other keys
    private void keyKeyTyped(KeyEvent event) {
        if(event.getKeyCode()==37){
            //jLabel0.setText("uparrow");
            jSlider0.setValue(9);
        }
        jLabel0.setText("keyType");


        this.requestFocus();
    }
}

Answer 1

else if(event.getKeyCode()==39){

切勿使用带有魔数(Magic Number)的代码。如果需要，定义静态变量。但是，在这种情况下，您不需要这样做，因为它已经为您完成了:

KeyEvent.VK_RIGHT

要让面板消失，您需要启动 Swing 计时器，以便在面板显示后 20 秒内触发。然后，每当按键事件或鼠标事件更改面板上的值时，您都可以重新启动计时器。

阅读 Swing 教程中关于 How to Use Timers 的部分了解更多信息。

如果这是您正在使用的模式对话框，您甚至可以使用 Application Inacdtivity来帮助你。