不知道我的代碼有什么問題。 Java GUI

Question

我正在嘗試制作一個帶有圖像的組合框。 我收到此錯誤：

注意：C：\\ Users \\ Kyle \\ Desktop \\ TUSEG \\ Program \\ ProductDemo.java使用未經檢查或不安全的操作。 注意：使用-Xlint：unchecked重新編譯以獲取詳細信息。

無論如何，當它嘗試繪制一張照片時，每次都會得到：

找不到文件：C：\\ Users \\ Kyle \\ Desktop \\ TUSEG \\ Program \\ images \\ microsoft \\ Xbox 360 Controller（PC）.jpg
找不到文件：C：\\ Users \\ Kyle \\ Desktop \\ TUSEG \\ Program \\ images \\ microsoft \\ Wireless Laser Mouse 5000.jpg

路徑絕對是正確的。 我不確定我的問題是什么。 如果有人可以看看這個並為我提供幫助？

    package components;

    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    import java.util.*;

    public class ProductDemo extends JPanel
                      implements ActionListener {
JLabel picture;

public ProductDemo() {
    super(new BorderLayout());

    String pMS[] = new String[23];
    pMS[0] = ("LifeChat LX-3000");
    pMS[1] = ("LifeChat ZX-6000");
    pMS[2] = ("Wireless Notebook Presenter 8000");
    pMS[3] = ("Arc Mouse");
    pMS[4] = ("Bluetooth Notebook Mouse 5000");
    pMS[5] = ("Explorer Mouse");
    pMS[6] = ("Explorer Mini Mouse");
    pMS[7] = ("Sidewinder X8 Mouse");
    pMS[8] = ("Wireless Laser Mouse 5000");
    pMS[9] = ("Wireless Mobile Mouse 3000");
    pMS[10] = ("Wireless Mobile Mouse 6000");
    pMS[11] = ("Arc Keyboard");
    pMS[12] = ("Bluetooth Mobile Keyboard 6000");
    pMS[13] = ("Sidewinder X4 Keyboard");
    pMS[14] = ("Sidewinder X6 Keyboard");
    pMS[15] = ("Ergonomic Desktop 7000");
    pMS[16] = ("Wireless Desktop 3000");
    pMS[17] = ("Wireless Laser Desktop 6000 v2.0");
    pMS[18] = ("Wireless Media Desktop 1000");
    pMS[19] = ("Windows Server 2008 Enterprise");
    pMS[20] = ("Notebook Cooling Base");
    pMS[21] = ("Xbox 360 Controller (PC)");
    pMS[22] = ("Xbox 360 Controller");
    Arrays.sort(pMS);

    //Indices start at 0, so 4 specifies the last index of the product.
    JComboBox msList = new JComboBox(pMS);
    msList.setSelectedIndex(22);
    msList.addActionListener(this);

    //Set up the picture.
    picture = new JLabel();
    picture.setFont(picture.getFont().deriveFont(Font.ITALIC));
    picture.setHorizontalAlignment(JLabel.CENTER);
    updateLabel(pMS[msList.getSelectedIndex()]);
    picture.setBorder(BorderFactory.createEmptyBorder(10,0,0,0));

    //height + width
    picture.setPreferredSize(new Dimension(100, 100));

    //Lays out the demo.
    add(msList, BorderLayout.PAGE_START);
    add(picture, BorderLayout.PAGE_END);
    setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
}

/** Listens to the combo box. */
public void actionPerformed(ActionEvent e) {
    JComboBox cb = (JComboBox)e.getSource();
    String pMS = (String)cb.getSelectedItem();
    updateLabel(pMS);
}

protected void updateLabel(String name) {
    ImageIcon icon = createImageIcon("C:\\Users\\Kyle\\Desktop\\TUSEG\\Program\\images\\microsoft\\" + name + ".jpg");
    picture.setIcon(icon);
    if (icon != null) {
        picture.setText(null);
    }
    else {
        picture.setText("Image not found");
    }
}

/** Returns an ImageIcon, or null if the path was invalid. */
protected static ImageIcon createImageIcon(String path) {
    java.net.URL imgURL = ProductDemo.class.getResource(path);
    if (imgURL != null) {
        return new ImageIcon(imgURL);
    } else {
        System.err.println("Couldn't find file: " + path);
        return null;
    }
}

/**
 * Create the GUI and show it.  For thread safety,
 * this method should be invoked from the
 * event-dispatching thread.
 */
private static void createAndShowGUI() {
    //Create and set up the window.
    JFrame frame = new JFrame("ProductDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //Create and set up the content pane.
    JComponent newContentPane = new ProductDemo();
    newContentPane.setOpaque(true); //content panes must be opaque
    frame.setContentPane(newContentPane);

    //Display the window.
    frame.pack();
    frame.setVisible(true);
}

public static void main(String[] args) {
    //Schedule a job for the event-dispatching thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}
}

Answer 1

您似乎在混淆基於File的路徑。

C:\Users\Kyle\Desktop\TUSEG\Program\images\microsoft\Xbox 360 Controller (PC).jpg

..具有在getResource(String)使用的相對引用，例如：

"images/microsoft/Xbox 360 Controller (PC).jpg"

getResource()方法期望使用正斜杠的字符串，該斜杠相對於應用程序的運行時類路徑（因此，通常將images目錄等添加到Jar中）。 為了確保它可以在任何包的類中使用，請在字符串前面加上/ 。

"/images/microsoft/Xbox 360 Controller (PC).jpg"

getResource()方法將返回URL ，因此請確保使用與URL兼容的構造函數。

Answer 2

確定是要從文件系統還是從應用程序的類路徑加載圖像。

如果從文件系統，請使用文件IO加載圖標，或使用以文件名作為參數的構造函數：

ImageIcon icon = new ImageIcon("c:\\....jpg");

如果來自類路徑，則該路徑是從類路徑的根開始的/分隔路徑，並且圖像應存儲在與您的類相同的目錄/ jar中（或存儲在類路徑中的另一個目錄/ jar中）：

ImageIcon icon = new ImageIcon(ProductDemo.class.getResource("/path/to/image.jpg"));

參見http://docs.oracle.com/javase/6/docs/api/javax/swing/ImageIcon.html和http://docs.oracle.com/javase/6/docs/api/java/lang/Class的.html＃的getResource％28java.lang.String 29％