java - 在运行时从另一个 JPanel 中的单独类文件添加自定义 JPanel

Question

我在一个单独的类文件中制作了一个自定义的 JPanel，其中包含一些参数，名为 itemCard ，我试图通过在另一个 jframe 中的另一个 jpanel(contentAreaPane) 中的参数中给出值来添加它的实例( mainPage.java) 按钮 (jButton1) 的 actionPerformed 事件的类文件

itemCard.java

import javax.swing.*;
import Resources.colors.MaterialColor;
import Resources.fonts.*;

/**
 *
 * @author Aditya
 */
public class itemCard extends JPanel {

    /**
     * Creates new form itemCard
     */

    public String name,price,retailer, prodID;

    /**
     * Takes four parameters, first is product ID which is a String, second is product
     * name which is a String, third is price which is a String,
     *  fourth is retailer name which is a String.
     */
    public itemCard(String prodID, String productName, String price, String retailer) {
        this.name = productName;
        this.price = price;
        this.retailer = retailer;
        this.prodID = prodID;


        initComponents();


    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        imageIconHolder = new javax.swing.JLabel();
        detailPane = new javax.swing.JPanel();
        priceTag = new javax.swing.JLabel();
        jScrollPane2 = new javax.swing.JScrollPane();
        jTextArea1 = new javax.swing.JTextArea();

        setBackground(new java.awt.Color(255, 255, 255));
        setBorder(new javax.swing.border.LineBorder(MaterialColor.BLUE_200, 2, true));
        setPreferredSize(new java.awt.Dimension(250, 300));
        addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseEntered(java.awt.event.MouseEvent evt) {
                formMouseEntered(evt);
            }
            public void mouseExited(java.awt.event.MouseEvent evt) {
                formMouseExited(evt);
            }
        });
        setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout());

        imageIconHolder.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
        imageIconHolder.setHorizontalTextPosition(javax.swing.SwingConstants.CENTER);
        imageIconHolder.setMaximumSize(new java.awt.Dimension(250, 200));
        imageIconHolder.setMinimumSize(new java.awt.Dimension(250, 200));
        imageIconHolder.setPreferredSize(new java.awt.Dimension(250, 200));
        add(imageIconHolder, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 0, 250, 200));

        detailPane.setBackground(MaterialColor.LIGHTBLUE_800);
        detailPane.setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout());

        priceTag.setBackground(MaterialColor.PURPLE_800);
        priceTag.setFont(Montserrat.REGULAR.deriveFont(25f));
        priceTag.setForeground(new java.awt.Color(255, 255, 255));
        priceTag.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
        priceTag.setText(price);
        priceTag.setHorizontalTextPosition(javax.swing.SwingConstants.CENTER);
        priceTag.setMaximumSize(new java.awt.Dimension(70, 100));
        priceTag.setMinimumSize(new java.awt.Dimension(70, 100));
        priceTag.setOpaque(true);
        priceTag.setPreferredSize(new java.awt.Dimension(70, 100));
        detailPane.add(priceTag, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 0, 70, 100));

        jScrollPane2.setBorder(null);
        jScrollPane2.setHorizontalScrollBarPolicy(javax.swing.ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
        jScrollPane2.setVerticalScrollBarPolicy(javax.swing.ScrollPaneConstants.VERTICAL_SCROLLBAR_NEVER);
        jScrollPane2.setEnabled(false);
        jScrollPane2.setPreferredSize(new java.awt.Dimension(180, 100));

        jTextArea1.setEditable(false);
        jTextArea1.setBackground(MaterialColor.DEEPPURPLE_700);
        jTextArea1.setColumns(20);
        jTextArea1.setFont(Roboto.THIN.deriveFont(20f)
        );
        jTextArea1.setForeground(new java.awt.Color(51, 51, 51));
        jTextArea1.setLineWrap(true);
        jTextArea1.setRows(5);
        jTextArea1.setText(((name.length()>51)?(name.substring(0, 48)+"...") : (name)) +"\n"+ ((retailer.length()>14)?(retailer.substring(0, 14)+"...") : (retailer)));
        jTextArea1.setToolTipText(name+"\n"+retailer);
        jTextArea1.setWrapStyleWord(true);
        jTextArea1.setBorder(null);
        jTextArea1.setMargin(new java.awt.Insets(7, 5, 7, 5));
        jTextArea1.setRequestFocusEnabled(false);
        jScrollPane2.setViewportView(jTextArea1);

        detailPane.add(jScrollPane2, new org.netbeans.lib.awtextra.AbsoluteConstraints(70, 0, 180, 100));

        add(detailPane, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 200, 250, 100));
    }// </editor-fold>                        

    private void formMouseEntered(java.awt.event.MouseEvent evt) {                                  
        this.setBorder(new javax.swing.border.LineBorder(MaterialColor.BLUE_400, 3, true));
        detailPane.setBackground(MaterialColor.LIGHTBLUE_900);
    }                                 

    private void formMouseExited(java.awt.event.MouseEvent evt) {                                 
        this.setBorder(new javax.swing.border.LineBorder(MaterialColor.BLUE_200, 2, true));
        detailPane.setBackground(MaterialColor.LIGHTBLUE_800);
    }                                

    // Variables declaration - do not modify                     
    private javax.swing.JPanel detailPane;
    private javax.swing.JLabel imageIconHolder;
    private javax.swing.JScrollPane jScrollPane2;
    private javax.swing.JTextArea jTextArea1;
    private javax.swing.JLabel priceTag;
    // End of variables declaration                   
}

这是我的按钮的 actionperformed 事件监听器:

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        try{
            JPanel itemcard = new itemCard("123456789AB","Inspiron 7567 Intel Core i5 DELL Laptop","68K","CloudTail Pvt. Ltd.");
            contentAreaPane.add(itemcard);
            contentAreaPane.revalidate();
            contentAreaPane.repaint();



        }catch(Exception e){
            e.printStackTrace();
        }
    }

但是，这不起作用，即单击 jButton1 时不会创建新的 itemCard JPanel 并在 contentAreaPane JPanel 中显示，并给出以下错误:

java.lang.IllegalArgumentException
at org.netbeans.lib.awtextra.AbsoluteLayout.addLayoutComponent(Unknown Source)
at java.desktop/java.awt.Container.addImpl(Container.java:1152)
at java.desktop/java.awt.Container.add(Container.java:436)
at AppFrames.mainPage.jButton1ActionPerformed(mainPage.java:887)
at AppFrames.mainPage$31.actionPerformed(mainPage.java:619)

如何解决？

Answer 1

在容器文档中，列出了以下异常(exception)情况:

IllegalArgumentException - if index is invalid; if comp is a child of this container, the valid range is [-1, getComponentCount()-1]; if component is not a child of this container, the valid range is [-1, getComponentCount()]
IllegalArgumentException - if comp is an ancestor of this container
IllegalArgumentException - if adding a window to a container

我认为你必须在条件 2 或 3 的情况下得到这个