组件在添加时删除图像

Question

我目前遇到JFrame和图片问题。该程序使用Applet然后将其添加到不同类中的JFrame，因此它可以作为Applet或Application运行。目前，该框架仅包含少量图像，而不包含任何组件。我最近尝试使用绝对定位添加一个JTextField（LayoutManger为null）并且它工作正常，除了删除所有图像，只留下一个JTextField。为什么会这样？我该如何解决？我的代码发布在下面。谢谢！

主类（创建小程序和图像）：

package net.xenix.src;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Rectangle2D;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import javax.swing.ImageIcon;
import javax.swing.JApplet;
import javax.swing.JComponent;
import javax.swing.Timer;

public class XenixMain extends JApplet implements ActionListener
{
private static final long serialVersionUID = 1L;

private static int pixelSize = 2;

public static Dimension size = new Dimension(1600, 900);
public static Dimension pixel = new Dimension(size.width / pixelSize, size.height /         pixelSize);

public static String name = "Xenix";

public static final int WIDTH = 1600;
public static final int HEIGHT = 900;

//Finding player Windows name
static String username = System.getProperty("user.name");

public static int secondsCount = 0;

//Shortcut to image directory
public static String imagePath = "C:\\Users\\" + username + "\\Desktop\\Xenix Dev\\Xenix\\resources\\graphics\\";

private static PaintSurface canvas;

public static ImageIcon XenixBackgroundIcon = new ImageIcon(imagePath + "XenixBackground.png");
public static Image XenixBackground = XenixBackgroundIcon.getImage();

public static ImageIcon XenixLogoIcon = new ImageIcon(imagePath + "XenixLogo.png");
public static Image XenixLogo = XenixLogoIcon.getImage();

public static ImageIcon HeartContainerFullIcon = new ImageIcon(imagePath + "HeartContainerFull.png");
public static Image HeartContainerFull = HeartContainerFullIcon.getImage();

public static ImageIcon HeartContainer9Icon = new ImageIcon(imagePath + "HeartContainer9.png");
public static Image HeartContainer9 = HeartContainer9Icon.getImage();

public static ImageIcon HeartContainer8Icon = new ImageIcon(imagePath + "HeartContainer8.png");
public static Image HeartContainer8 = HeartContainer8Icon.getImage();

public static ImageIcon HeartContainer7Icon = new ImageIcon(imagePath + "HeartContainer7.png");
public static Image HeartContainer7 = HeartContainer7Icon.getImage();

public static ImageIcon HeartContainer6Icon = new ImageIcon(imagePath + "HeartContainer6.png");
public static Image HeartContainer6 = HeartContainer6Icon.getImage();

public static ImageIcon HeartContainer5Icon = new ImageIcon(imagePath + "HeartContainer5.png");
public static Image HeartContainer5 = HeartContainer5Icon.getImage();

public static ImageIcon HeartContainer4Icon = new ImageIcon(imagePath + "HeartContainer4.png");
public static Image HeartContainer4 = HeartContainer4Icon.getImage();

public static ImageIcon HeartContainer3Icon = new ImageIcon(imagePath + "HeartContainer3.png");
public static Image HeartContainer3 = HeartContainer3Icon.getImage();

public static ImageIcon HeartContainer2Icon = new ImageIcon(imagePath + "HeartContainer2.png");
public static Image HeartContainer2 = HeartContainer2Icon.getImage();

public static ImageIcon HeartContainer1Icon = new ImageIcon(imagePath + "HeartContainer1.png");
public static Image HeartContainer1 = HeartContainer1Icon.getImage();

public static ImageIcon HeartContainerDepletedIcon = new ImageIcon(imagePath + "HeartContainerDepleted.png");
public static Image HeartContainerDepleted = HeartContainerDepletedIcon.getImage();

public static ImageIcon HealthTextIcon = new ImageIcon(imagePath + "HealthText.png");
public static Image HealthText = HealthTextIcon.getImage();

public static ImageIcon ForwardSlashIcon = new ImageIcon(imagePath + "ForwardSlash.png");
public static Image ForwardSlash = ForwardSlashIcon.getImage();

public Timer timer = new Timer(1000, this);

public void start()
{
    timer.setInitialDelay(0);
    timer.start(); 
}

public void stop()
{
    timer.stop();
}

public void actionPerformed(ActionEvent e)
{
    secondsCount++;

    System.out.println(secondsCount);
}

public void init()
{
    this.setSize(WIDTH, HEIGHT);
    canvas = new PaintSurface();
    this.add(canvas, BorderLayout.CENTER);

    ScheduledThreadPoolExecutor executor = 
        new ScheduledThreadPoolExecutor(3);
    executor.scheduleAtFixedRate(
        new AnimationThread(this), 
        0L, 20L, TimeUnit.MILLISECONDS);
}
}

class AnimationThread implements Runnable   
{
JApplet c;

public AnimationThread(JApplet c)
{

    this.c = c;
}

public void run()
{
    c.repaint();
}
}

class PaintSurface extends JComponent
{
private static final long serialVersionUID = 1L;

public void paint(Graphics g)
{
    Graphics2D g2 = (Graphics2D)g;
    g2.setRenderingHint(
        RenderingHints.KEY_ANTIALIASING, 
        RenderingHints.VALUE_ANTIALIAS_ON);

    Shape screenDisplay = new Rectangle2D.Float(
            450, 175, 700, 500);

        g2.setColor(Color.DARK_GRAY);
        g2.fill(screenDisplay);

    /*
     * START TITLE SCREEN CREATION
     */

    if(XenixMain.secondsCount > 0)
    {
        g.drawImage(XenixMain.XenixLogo, 500, 500, this);
    }


    g.drawImage(XenixMain.XenixBackground, 0, 0, this);


    /*
     * END TITLE SCREEN CREATION
     */
    }
} 

JFrame Class（创建JFrame并添加Applet）：

package net.xenix.src ;

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

public class XenixApplicationWindow extends JFrame
{
private static final long serialVersionUID = 1L;

static XenixMain xenix = new XenixMain();

static ImageIcon xenixIcon = new ImageIcon(XenixMain.imagePath + "XenixIcon.png");

public static void main(String[] args)
{
    new XenixApplicationWindow();
}

public XenixApplicationWindow()
{
    JFrame frame = new JFrame();
    JTextField userInput = new JTextField(15);
    JPanel panel1 = new JPanel(null);
    frame.add(xenix);
    frame.setSize(1600, 900);
    frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
    frame.setResizable(true);
    frame.setIconImage(xenixIcon.getImage());
    userInput.setBounds(0, 0, 120, 10);
    panel1.add(userInput);
    frame.add(panel1);

    frame.setContentPane(panel1);

    frame.setLocationRelativeTo(null);
    frame.setTitle("Xenix");

    xenix.init();
    xenix.start();

    frame.setVisible(true);
}
}

Answer 1

看看这个例子，看看这是否有所帮助。有关上述主题的一些信息，请参阅此link。如果仍然不清楚，请告诉我。

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;

public class BackgroundExample {

    private JTextField tField;
    private JButton button;

    private CustomPanel contentPane;

    private void displayGUI() {
        JFrame frame = new JFrame("Background Example");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        contentPane = new CustomPanel();
        contentPane.setLayout(new GridBagLayout());

        JPanel componentPanel = new JPanel();
        componentPanel.setOpaque(false);
        tField = new JTextField("Nothing to display yet...", 20);
        button = new JButton("Click me not!");
        componentPanel.add(tField);
        componentPanel.add(button);

        contentPane.add(componentPanel);

        frame.setContentPane(contentPane);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        Runnable runnable = new Runnable() {
            @Override
            public void run() {
                new BackgroundExample().displayGUI();
            }
        };
        EventQueue.invokeLater(runnable);
    }
}

class CustomPanel extends JPanel {

    private BufferedImage bImage;

    public CustomPanel() {
        try {
            bImage = ImageIO.read(new URL("http://i.imgur.com/fHiBMwI.jpg"));
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
    }

    @Override
    public Dimension getPreferredSize() {
        return (bImage != null ? new Dimension(
            bImage.getWidth(), bImage.getHeight()) : new Dimension(400, 400));
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawImage(bImage, 0, 0, this);
    }
}