标签: jcombobox

我知道我错过了一些简单的东西,我想让组合框来访问数组.

package my.freelancebillingapp;
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.ArrayList;
import javax.swing.*;

public class billingInfoUI extends javax.swing.JFrame {

    public billingInfoUI() {
        initComponents();
    }

    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        hoursWorked = new javax.swing.JTextField();
        jLabel1 = new javax.swing.JLabel();
        flatRate = new javax.swing.JTextField();
        jScrollPane1 = new javax.swing.JScrollPane();
        workType = new javax.swing.JList();
        jScrollPane2 = new javax.swing.JScrollPane();
        jList2 = new javax.swing.JList();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jComboBox1 = …

jComboBox.removeAllItems在添加项目之前不会抱怨(在从配置文件填充JComboBox之前调用它一次).单步执行此代码,我看到jComboBox.removeAllItems调用JComboBox.removeAllItems调用调用fireIntervalRemoved的DefaultComboBoxModel.removeAllElements.jComboBox中有七个项目,fireIntervalRemoved中的循环在抛出NullPointerException之前执行了大约四次.有任何想法吗？

public class MyClass extends javax.swing.JFrame {
    ...
    private void updateComboBox() {
        try {
            jComboBox.removeAllItems();
            ...
public class JComboBox ...
    ...
    public void removeAllItems() {
        checkMutableComboBoxModel();
        MutableComboBoxModel model = (MutableComboBoxModel)dataModel;
        int size = model.getSize();
        if ( model instanceof DefaultComboBoxModel ) {
            ((DefaultComboBoxModel)model).removeAllElements();
            ...
public class DefaultComboBoxModel ...
    ...
    public void removeAllElements() {
        if ( objects.size() > 0 ) {
            int firstIndex = 0;
            int lastIndex = objects.size() - 1;
            objects.removeAllElements();
        selectedObject = null;
            fireIntervalRemoved(this, firstIndex, lastIndex);
            ...
public abstract class …

• 目的:在每个项目中使用具有不同背景颜色和文本的JComboBox.
• 我的问题:背景颜色没有改变,文本不是我在setText中设置的,它已在System.out.println中正确显示.getSelectedIndex()效果很好.

捕获:http://i.stack.imgur.com/EgfZs.png

以下是我已经消化并尝试错误Dr.Google显示的代码:

public class ColorCode{
   private Color color;
   private String alias;
   ...
}
public class ElectronicColorCode extends JFrame implements ActionListener{
   private JComboBox[] selections = new JComboBox[4];
   ...
   public ElectronicColorCode(){
      for(int i=0; i<selections.length; i++){
         selections[i] = new JComboBox();
         for(int j=0; j<tolColorSets.length; j++)
            selections[i].addItem(new ComboBoxRenderer(colorSets[j]));
      }
      selections[i].addActionListener(this);
      ...
   }
}
class ComboBoxRenderer extends JLabel implements ListCellRenderer{
   private ColorCode colorCode;

   public ComboBoxRenderer(ColorCode colorCode){
      super();
      this.colorCode = colorCode;
      setBackground(colorCode.getColor());
      setText(colorCode.getAlias());
      System.out.println(colorCode.getAlias());
   }

   public Component getListCellRendererComponent(JList list, Object …

我正在尝试将文本文件的每一行复制到jcomboBox中,但它只显示jcomboBox中文本文件的第一行...我不明白为什么.你能解释一下我有什么问题吗？

(...)
BufferedReader in;
    String read;

        try {
            in = new BufferedReader(new FileReader("D:/File.txt"));


            read = in.readLine();

            lines[w]=read;

             ++w;

            in.close();
        }catch(IOException e){
            System.out.println("There was a problem:" + e);
        }

    combo1 = new JComboBox(lines);

    combo1.setPreferredSize(new Dimension(100,20));
    combo1.setForeground(Color.blue);


    JPanel top = new JPanel();
    top.add(label);
    top.add(combo1);

    combo1.addActionListener(new ActionFichiers());

    container.add(top, BorderLayout.NORTH);
    this.setContentPane(container);
    this.setVisible(true);            
    }
(...)

我有一个jCombobox,我想移动用于显示左侧选项的按钮.知道如何做到这一点？

---------------------------
|\/ |Combobox             |
--------------------------

谢谢

我有3个JCombobox IN MY Converter程序一个用于类别,两个用于选择要执行的功能; 我希望程序做的是当用户在一个JCombobox中选择一个类别时,两个JCombobox将自动更改与所选类别相关的内容(当选择一个其他的chage值时,请帮助我使用JCombobox更改项目的功能);

下面的代码用于根据所选日期使用可用时间填充组合框.

但是由于某种原因,组合框正在存储数据示例的内存地址:

Restaurant.Time@1a28362
Restaurant.Time@5fcf29
...

我知道它得到了正确的时间.但是,我如何实际打印出实际物品？

TimeList times = dbConnector.selectTimes(lblDay.getText());//lblDay stores the date from the jCalendar button
cmbNewResTimes.removeAllItems();
for (int pos1 = 0; pos1 < times.size(); pos1++) {
    cmbNewResTimes.addItem(times.getTimeAt(pos1).toString());
}

Eclipse IDE在Jcombobox上显示错误,该错误表明JcomboBox不能被参数化,例如:如下所示的行

private final JComboBox<LaborHelper> labourname = new JComboBox<LaborHelper>();

这里我的项目执行环境是javaSE1.6

基本上我需要一个字段(用于Swing),如果指定的数据不在提供的列表中,用户可以输入数据Combo-box.怎么做到这一点？

我试图从我的一个JComboBoxes中删除一个项目监听器.下面是代码.

clientNameCombo.removeItemListener(clientNameCombo.getItemListeners()[clientNameCombo.getItemListeners().length-1]);

我动态添加ItemListener到上面的组合框.但是,有时当上面的代码运行时,它会给出错误:

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: -1
    at UI.MainUIHolder$CoreClientOtherPaymentTypeComboAction.itemStateChanged(MainUIHolder.java:10031)
    at javax.swing.JComboBox.fireItemStateChanged(JComboBox.java:1223)
    at javax.swing.JComboBox.selectedItemChanged(JComboBox.java:1280)
    at javax.swing.JComboBox.contentsChanged(JComboBox.java:1329)
    at javax.swing.AbstractListModel.fireContentsChanged(AbstractListModel.java:118)
    at javax.swing.DefaultComboBoxModel.setSelectedItem(DefaultComboBoxModel.java:93)
    at javax.swing.JComboBox.setSelectedItem(JComboBox.java:576)
    at javax.swing.JComboBox.setSelectedIndex(JComboBox.java:622)
    at javax.swing.plaf.basic.BasicComboPopup$Handler.mouseReleased(BasicComboPopup.java:834)
    at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:290)
    at java.awt.Component.processMouseEvent(Component.java:6525)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
    at javax.swing.plaf.basic.BasicComboPopup$1.processMouseEvent(BasicComboPopup.java:498)
    at java.awt.Component.processEvent(Component.java:6290)
    at java.awt.Container.processEvent(Container.java:2234)
    at java.awt.Component.dispatchEventImpl(Component.java:4881)
    at java.awt.Container.dispatchEventImpl(Container.java:2292)
    at java.awt.Component.dispatchEvent(Component.java:4703)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4898)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4533)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4462)
    at java.awt.Container.dispatchEventImpl(Container.java:2278)
    at java.awt.Window.dispatchEventImpl(Window.java:2739)
    at java.awt.Component.dispatchEvent(Component.java:4703)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:746)
    at java.awt.EventQueue.access$400(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:697)
    at java.awt.EventQueue$3.run(EventQueue.java:691)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86)
    at java.awt.EventQueue$4.run(EventQueue.java:719)
    at java.awt.EventQueue$4.run(EventQueue.java:717) …