JLayeredPane未显示我的自定义JPanel

我无法让自定义面板显示使用JLayeredPanel。我目前正试图在第一层上创建一个黑色矩形，而在第二层上，我有一个自定义JPanel，它是一个图像幻灯片。幻灯片显示根本不会显示，只有在将其添加到框架时才能使用。有什么想法吗？JLayeredPane未显示我的自定义JPanel

代码：

import java.awt.Color; 
import java.awt.Container; 
import java.awt.Dimension; 
import java.awt.Image; 
import java.awt.Toolkit; 
import java.util.ArrayList; 

import javax.swing.ImageIcon; 
import javax.swing.JFrame; 
import javax.swing.JLayeredPane; 
import javax.swing.JPanel; 

public class GUI extends JFrame { 

    private Container pane; 
    private JPanel emptySlideShow; 
    private JLayeredPane layeredPane; 

    public GUI(){ 
     this.setVisible(true); 
     Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); 
     this.setBounds(0,0,screenSize.width, screenSize.height); 



     //  //Set up the content pane 
     //  pane = this.getContentPane(); //get the content pane to place components 
     //  pane.setLayout(null); //use absolute positioning (using Insets) 
     //  pane.setBackground(new Color(236, 236, 236)); //color the background 
     // 
     //  //Set up the main menu bar 
     this.emptySlideShow = new JPanel(); 
     this.emptySlideShow.setBounds(0,0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),250); 
     this.emptySlideShow.setBackground(new Color(0,0,0));  

     layeredPane = new JLayeredPane(); 
     layeredPane.setLayout(null); 
     layeredPane.add(this.emptySlideShow,new Integer(0)); 

     ArrayList<Image> slides = new ArrayList<Image>(); 

     Image image1 = new ImageIcon("pictures/slide1.png").getImage(); 
     slides.add(image1); 

     Image image2 = new ImageIcon("pictures/slide2.png").getImage(); 
     slides.add(image2); 

     ArrayList<String> transitions = new ArrayList<String>(); 
     transitions.add("PanLR"); 
     transitions.add("FadeOut"); 


     this.add(new SlideShow(slides,transitions)); 
     layeredPane.add(new SlideShow(slides,transitions),new Integer(1)); 


     this.add(layeredPane); 



    } 
}

来源

2015-08-31 Jon Sherman