JAVA时间动画

Question

我想做一个简单的动画使用计时器，添加和删除按钮，但我不知道我在哪里错了。另外我添加了两个打印只是为了验证。他们打印正确。我还观察到，如果我删除removeAll（）方法，它会添加按钮。

import java.awt.*; 
import java.awt.event.*; 

import javax.swing.*; 


public class Animation extends JPanel{ 
    JLabel l1 = new JLabel(new ImageIcon("tom1.png")); 
    JLabel l2 = new JLabel(new ImageIcon("tom2.png")); 
    JLabel l3 = new JLabel(new ImageIcon("tom3.png")); 
    JLabel l4 = new JLabel(new ImageIcon("tom4.png")); 
    JLabel l5 = new JLabel(new ImageIcon("tom5.png")); 
    JButton b1 = new JButton("HAHA"); 
    JButton b2 = new JButton(); 
    JPanel panel = new JPanel(); 

    public Animation(){ 
     setLayout(new BorderLayout()); 
     Timer time = new Timer(1000,new ActionListener(){ 
      public void actionPerformed(ActionEvent e){ 
       System.out.println("paint"); 
       add(b1, BorderLayout.CENTER); 
       repaint(); 
       revalidate(); 
       System.out.println("remove"); 
       removeAll(); 
       repaint(); 
       revalidate(); 

      } 
     }); 
     time.start(); 



    } 


    public static void main(String[] args) { 
     JFrame frame = new JFrame(); 
     frame.add(new Animation()); 
     frame.setVisible(true); 
     frame.setSize(1000,400); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

    } 



} 

Answer 1

就像在评论中说，要添加的按钮，然后取出真的后不久...

为了使按钮apprear一秒钟，dissapear其他的，你可以做一个标志，在定时器中做一件事，然后做另一件事。 你可以这样做：

package test; 

import java.awt.*; 
import java.awt.event.*; 

import javax.swing.*; 

public class Animation extends JPanel { 
    JLabel l1 = new JLabel(new ImageIcon("tom1.png")); 
    JLabel l2 = new JLabel(new ImageIcon("tom2.png")); 
    JLabel l3 = new JLabel(new ImageIcon("tom3.png")); 
    JLabel l4 = new JLabel(new ImageIcon("tom4.png")); 
    JLabel l5 = new JLabel(new ImageIcon("tom5.png")); 
    JButton b1 = new JButton("HAHA"); 
    JButton b2 = new JButton(); 
    JPanel panel = new JPanel(); 
    boolean isthere = false; 

    public Animation() { 
     setLayout(new BorderLayout()); 
     Timer time = new Timer(1000, new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 

       if (!isthere) { 
        System.out.println("paint"); 
        add(b1, BorderLayout.CENTER); 
        repaint(); 
        revalidate(); 

        isthere = !isthere; 
       } else { 

        System.out.println("remove"); 
        removeAll(); 
        repaint(); 
        revalidate(); 
        isthere = !isthere; 
       } 

      } 
     }); 
     time.start(); 

    } 

    public static void main(String[] args) { 
     JFrame frame = new JFrame(); 
     frame.add(new Animation()); 
     frame.setVisible(true); 
     frame.setSize(1000, 400); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

    } 

}