java使用Swing中的计时器显示一张图片5秒钟

Question

我正在尝试使用Timer为我的应用程序创建登录图片。其想法是，当用户打开应用程序时，他将看到一张图片5秒钟，然后应用程序将启动

我试过了，正如你在方法shoutoff()中看到的：

     /*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

package login;


import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Timer;

/**
 *
 * @author isslam
 */

public class login extends javax.swing.JFrame {
 Timer time;
    /**
     * Creates new form login
     */

    public login() {
        initComponents();
        setLocation(350, 200);
         time = new Timer(5000,new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent e) {
              dispose();
         }
     });
     time.setRepeats(false);

    }
 public void shoutoff(){
if (!time.isRunning()) {
        time.start();
    }
 }
    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setAlwaysOnTop(true);
        setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
        setLocationByPlatform(true);
        setUndecorated(true);
        setResizable(false);

        jLabel1.setIcon(new javax.swing.ImageIcon("C:\\Users\\isslam\\Desktop\\one_piece_marble_play_by_iviarker-d511vb0.jpg")); // NOI18N

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jLabel1)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jLabel1)
        );

        pack();
    }// </editor-fold>                        

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(login.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new login().setVisible(true);
               new login().shoutoff();
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JLabel jLabel1;
    // End of variables declaration                   
}

Answer 1

首先在构造函数中创建一次Timer。Timer也应该只关闭login的当前实例

public login() {
    //...
    time = new Timer(5000,new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent e) {
              dispose();
         }
     });
     timer.setRepeats(false);
}

在shoutoff方法中，启动计时器

public void shoutoff(){
    if (!time.isRunning()) {
        timer.start();
    }
}

更详细地看一下How to use Swing Timers

您可能希望有一个通读Code Conventions for the Java TM Programming Language，它将使人们更容易阅读您的代码，也使您更容易阅读其他代码