如何强制 JLabels 重叠

Question

我知道我仍然需要将 string 转换为 int 并为 providerID 和 providerPrice 加倍，以便我可以设置它们，然后再存储它们；我希望我能很好地解决这个问题。我似乎找不到的是如何使 JLabels 正确对齐。 cloudBack 标签应该是主背景，每组 JLabel 和 JTextField 应该在与主背景重叠的单独一行上，底部有 3 个 JButton。我如何让他们去正确的地方？顺便说一句，源 .png 是 400x224 像素 包新提供者；

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;

/*@Michael Christopher,  author/owner */
public class NewProvider {
/** @param args the command line arguments*/
public static void createGUI() {
    // Create the window
    JFrame mainFrame = new JFrame ("NewProvider");
    mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //Create the MenuBar
    JMenuBar maintenanceMenuBar = new JMenuBar ();
    maintenanceMenuBar.setOpaque(true);
    maintenanceMenuBar.setBackground(new Color(176,224,230));
    maintenanceMenuBar.setPreferredSize(new Dimension(400, 20));

    //create variables
    int providerID;
    String providerName;
    Double providerPrice;
    int addProviderCheck;
    String[] options = {"Yes","No"};

    //create image icon, labels, and JTextFields
    JLabel cloudBack;
    cloudBack = new JLabel (new ImageIcon("images/CloudBack.png"));
    JLabel labelID = new JLabel ("New ProviderID");
    JTextField textID = new JTextField("providerID \n", 10);
    JLabel labelName = new JLabel ("New Provider Name");
    JTextField textName = new JTextField("Provider Name \n", 20);
    JLabel labelPrice = new JLabel ("New Provider Price");
    JTextField textPrice = new JTextField ("Price \n", 5);
    //make Submit, Clear, & Exit buttons
    JButton submit = new JButton("Submit");   
    JButton clear = new JButton("Clear");
    JButton exit = new JButton("Exit");

    /*Set the FlowLayout to arrange the window, setting labels, text fields,
    menubar, background, and orientation*/
    FlowLayout newProviderLayout = new FlowLayout();
    mainFrame.setLayout(newProviderLayout);
    mainFrame.setJMenuBar(maintenanceMenuBar);
    mainFrame.add(cloudBack, BorderLayout.CENTER);
    mainFrame.add(labelID);
    mainFrame.add(textID);
    mainFrame.add(labelName);
    mainFrame.add(textName);
    mainFrame.add(labelPrice);
    mainFrame.add(textPrice);
    mainFrame.add(submit);
    mainFrame.add(clear);
    mainFrame.add(exit);

    //ActionListener for Submit button
    submit.addActionListener(new ActionListener()
    {           public void actionPerformed(ActionEvent e) {
                    String ID = textID.getText();
                    String Name = textName.getText();
                    String Price = textPrice.getText();
            int submitPress = JOptionPane.showOptionDialog(null,
     "ProviderID: " + ID + "\n" + "Provider Name: " + Name +"\n" + "Provider Price: " + Price,
     "Please Verify Content",JOptionPane.YES_NO_OPTION,JOptionPane.WARNING_MESSAGE,null, options,options[0]); 
if (submitPress <= 0) {                  
    //Store Displayed data
    System.out.println(ID);
    System.out.println(Name);
    System.out.println(Price);
    /*providerID = ID;
    providerName = Name;
    providerPrice = Price;  */
    textID.setText("Confirmed");
}
else if (submitPress > 0) {      
            textID.setText("providerID");
            textName.setText("Provider Name");
            textPrice.setText("Price"); }
        }
    });
    //ActionListener for clear button
    clear.addActionListener(new ActionListener()
    {    @Override
        public void actionPerformed(ActionEvent e) {
            textID.setText("providerID");
            textName.setText("Provider Name");
            textPrice.setText("Price"); }
    });
    //ActionListener for Exit Button
    exit.addActionListener(new ActionListener() 
    {   @Override
        public void actionPerformed(ActionEvent e) {
            mainFrame.setVisible(false);
            mainFrame.dispose(); }
    });
//verify intent to add new provider to system before continuing
addProviderCheck = JOptionPane.showOptionDialog(null,
     "This will add a new service provider to the database.\n" 
    + "Are you sure you wish to continue?",
     "Please Verify Intent",JOptionPane.YES_NO_OPTION,JOptionPane.QUESTION_MESSAGE,null, options,options[0]); 
if (addProviderCheck <= 0) {
              //Display Window
    mainFrame.pack();
    mainFrame.setSize(400, 400);
    mainFrame.setVisible(true);}
else { //else close app
    mainFrame.setVisible(false);
    mainFrame.dispose();
}
}
public static void main(String[] args){
    //draw and show the GUI
    javax.swing.SwingUtilities.invokeLater(() -> {
        createGUI();
    });        
    //store new provider data
    }
}

Answer 1

不要在 JLabel 中显示 CloudBack.jpg，而是考虑使用 g.drawImage(...) 在 JPanel 的 paintComponent 方法中绘制它，然后将其他组件放置到此绘图 JPanel 上。请注意，如果您在绘图 JPanel 上添加任何其他 JPanel，请确保通过 setOpaque(false) 将非绘图 JPanel 设置为不透明。

我还建议您不要使用 FlowLayout 作为您的主要 GUI 布局，因为它不会以令人愉悦、易于使用和查看的方式添加您的组件。除了 BorderLayout 之外，考虑使用 GridBagLayout 或 MigLayout。