有两个问题：
图片路径没有写对，图片在 src 下，图片路径应是 src/海洋.png，正确的写法应是 image = new ImageIcon("src/海洋.png")
image = new ImageIcon("src/海洋.png") 应该放在 label = new JLabel(image)前面。
如下例：
import javax.swing.*class JPanelDemo extends JPanel {
JLabel label
JTextField text
JButton button
ImageIcon image
public JPanelDemo() {
image = new ImageIcon("src/test.png")
label = new JLabel(image)
text = new JTextField(20)
button = new JButton("确定")
add(label)
add(text)
add(button)
}
}
public class App extends JFrame {
public App() {
this.setSize(500, 400)
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)
this.add(new JPanelDemo())
}
public static void main(String[] args) {
new App().setVisible(true)
}
}
--------------------------------------------------------------------------------------------import java.awt.Graphics
import javax.swing.ImageIcon
import javax.swing.JFrame
import javax.swing.JPanel
public class ImageApp extends JFrame {
public ImageApp() {
setDefaultCloseOperation(EXIT_ON_CLOSE)
setLocationRelativeTo(null)
setSize(400, 300)
setResizable(false)
getContentPane().setLayout(null)
JPanel panel = new ImagePanel()
panel.setBounds(0, 0, 400, 300)
getContentPane().add(panel)
setVisible(true)
}
public static void main(String[] args) {
new ImageApp()
}
class ImagePanel extends JPanel {
public void paint(Graphics g) {
super.paint(g)
ImageIcon icon = new ImageIcon("D:\\14405937jqhjsppeninjf9.ico")
g.drawImage(icon.getImage(), 0, 0, 400, 300, this)
}
}
}
参考代码. 你可以对照修改
import java.awt.BorderLayoutimport java.awt.Image
import java.awt.Toolkit
import javax.swing.*
public class Picture extends JFrame {
private JLabel picture
public Picture() {
ImageIcon[] icons = new ImageIcon[4]//四张图的icon对象
String photopath = ""
for (int i = 1 i <= 4 i++) {
//这里的目录是我的图片所在的目录 1.gif~4.gif
photopath = "src/images/" + i + ".gif"
Image img = Toolkit.getDefaultToolkit().createImage(photopath)
icons[i-1] = new ImageIcon(img)
}
picture = new JLabel()
JPanel jp = new JPanel()
jp.add(picture)
add(jp,BorderLayout.CENTER)
setBounds(500, 200, 200, 200)
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE)
int n = Integer.parseInt(JOptionPane.showInputDialog("input: "))
//先设置Jlabel应该显示的图片
picture.setIcon(icons[n-1])
//然后才开始显示窗口
this.setVisible(true)
}
public static void main(String[] args) {
new Picture()
}
}
