将对象从ArrayList添加到JTable

Question

我想将对象添加到jtable中。没有例外或错误。对象在数组列表中添加，并且也在控制台上打印，但在JTable上不添加。...这是代码....

public class Table extends javax.swing.JFrame {
    ArrayList<Data>dataList = new ArrayList<Data>();
        public Table() {
            initComponents();
            connection ();
        }
        @SuppressWarnings("unchecked")
        // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
        private void initComponents() {
            jInternalFrame1 = new javax.swing.JInternalFrame();
            jScrollPane1 = new javax.swing.JScrollPane();
            jTable1 = new javax.swing.JTable();
            jButton1 = new javax.swing.JButton();
            jButton2 = new javax.swing.JButton();
            jInternalFrame1.setVisible(true);
            javax.swing.GroupLayout jInternalFrame1Layout = new javax.swing.GroupLayout(jInternalFrame1.getContentPane());
            jInternalFrame1.getContentPane().setLayout(jInternalFrame1Layout);
            jInternalFrame1Layout.setHorizontalGroup(
                jInternalFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGap(0, 0, Short.MAX_VALUE)
            );
            jInternalFrame1Layout.setVerticalGroup(
                jInternalFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGap(0, 0, Short.MAX_VALUE)
            );
            setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
            setPreferredSize(new java.awt.Dimension(600, 400));
            jTable1.setModel(new javax.swing.table.DefaultTableModel(
                new Object [][] {
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null},
                    {null, null, null, null, null, null, null}
                },
                new String [] {
                    "Date", "Node ID", "Voltage", "Temperature", "CO", "CO2", "Avability"
                }
            ) {
                Class[] types = new Class [] {
                    java.lang.Long.class, java.lang.Integer.class, java.lang.Double.class, java.lang.Double.class, java.lang.Integer.class, java.lang.Integer.class, java.lang.String.class
                };
                public Class getColumnClass(int columnIndex) {
                    return types [columnIndex];
                }
            });
            jTable1.setMaximumSize(new java.awt.Dimension(540, 380));
            jScrollPane1.setViewportView(jTable1);
            jButton1.setText("Fetch Records");
            jButton2.setText("Specific Node");
            javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
            getContentPane().setLayout(layout);
            layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                    .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jButton1)
                    .addGap(18, 18, 18)
                    .addComponent(jButton2)
                    .addGap(87, 87, 87))
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
            );
            layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGap(18, 18, 18)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(jButton1)
                        .addComponent(jButton2))
                    .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
            );
            pack();
        }// </editor-fold>                        
        /**
         * @param args the command line arguments
         */
        public void connection (){
             for(int i=0;i<5; i++){
                 Data data = new Data(i, 5.5, 32.0, 50, 60);
                dataList.add(data);
                System.out.println(dataList.get(i).getId());
                System.out.println(dataList.get(i).getVoltage());
                System.out.println(dataList.get(i).getTemperature());
                System.out.println(dataList.get(i).getCO());
                System.out.println(dataList.get(i).getCO2());
            }
             DefaultTableModel model = new DefaultTableModel();
             JTable table = new JTable(model); 
            //model.setRowCount(dataList.size());
             Object rowData[]=new Object[5];
           int row = 0;
           for(int i=0; i< 5; i++){
                rowData[0]=dataList.get(i).getId();
                rowData[1]=dataList.get(i).getVoltage();
                rowData[2]=dataList.get(i).getTemperature();
                rowData[3]=dataList.get(i).getCO();
                rowData[4]=dataList.get(i).getCO2();
                model.addRow(rowData);
                            }
            table.setModel(model);
            table.setVisible(true);
        }
        public static void main(String args[]) {
            java.awt.EventQueue.invokeLater(new Runnable() {
                public void run() {
                    new Table().setVisible(true);
                }
            });
            System.out.println();
        }

Answer 1

在您的连接方法中，您正在创建一个可JTable并将其填充数据，但切勿将其添加到GUI中。我怀疑您想做的是更改现有JTable中的数据，对吗？如果是这样，您将无法正确执行此操作。您需要在现有JTable的表模型中更新数据，或者以其他方式将现有JTable的TableModel设置为新的TableModel

public void connection (){
     for(int i=0;i<5; i++){
         Data data = new Data(i, 5.5, 32.0, 50, 60);
        dataList.add(data);
        System.out.println(dataList.get(i).getId());
        System.out.println(dataList.get(i).getVoltage());
        System.out.println(dataList.get(i).getTemperature());
        System.out.println(dataList.get(i).getCO());
        System.out.println(dataList.get(i).getCO2());
    }
     DefaultTableModel model = new DefaultTableModel();
/// ***** HERE IS WHERE YOU CREATE THE NEW JTABLE AND NEVER ADD IT TO ANYTHING ***** ///
     JTable table = new JTable(model); 
    //model.setRowCount(dataList.size());
     Object rowData[]=new Object[5];
   int row = 0;
   for(int i=0; i< 5; i++){
        rowData[0]=dataList.get(i).getId();
        rowData[1]=dataList.get(i).getVoltage();
        rowData[2]=dataList.get(i).getTemperature();
        rowData[3]=dataList.get(i).getCO();
        rowData[4]=dataList.get(i).getCO2();
        model.addRow(rowData);
                    }
    table.setModel(model);
    table.setVisible(true);
}