Java JTable 组合框验证

Question

我在这里尝试做三件事:

1. 首先，我试图让组合框在启动程序时显示“不提供”，在启动程序时它只显示任何内容，只有当我单击组合框时它才会显示该选项“喂食”和“不喂食”。

2. 其次，我尝试对组合框进行验证，当我接下来单击 JButton 时，它将验证组合框是否全部为“feed”，如果您继续下一步，否则会弹出“再次检查”的窗口

3. 最后，我想让前 4 列的单元格不可编辑，最后一列可编辑。

   public class DosageTableHelper  {
   private static JTable toDoTable;
   private static JScrollPane jpane;
   private static int counter=1;
   public static DefaultTableModel getElderlyFromQueryDos(String timing,String position) throws SQLException {
       SQLObject so = new SQLObject();
       ResultSet rs = null;
   
       if(timing.equalsIgnoreCase("Morning")){
           PreparedStatement stmt  = so.getPreparedStatementWithKey("SELECT morningdosage FROM et_elderly WHERE name = ?");
           stmt.setString(1,position);
           stmt.executeQuery();
           System.out.println(stmt);
           rs = stmt.getResultSet();
       }
       else if(timing.equalsIgnoreCase("Afternoon")){
           PreparedStatement stmt  = so.getPreparedStatementWithKey("SELECT afternoondosage FROM et_elderly WHERE name = ?");
           stmt.setString(1,position);
           stmt.executeQuery();
           System.out.println(stmt);
           rs = stmt.getResultSet();
       }
       else if(timing.equalsIgnoreCase("Noon")){
           PreparedStatement stmt  = so.getPreparedStatementWithKey("SELECT noondosage FROM et_elderly WHERE name = ?");
           stmt.setString(1,position);
           stmt.executeQuery();
           System.out.println(stmt);
           rs = stmt.getResultSet();
       }
       return (DefaultTableModel) buildTableModel(rs);
   }
   
   
   
   @SuppressWarnings("unchecked")
   public static DefaultTableModel buildTableModel(ResultSet rs) throws SQLException {
       ArrayList<DosageObject> DosageList=null;
   
   
       System.out.println(rs);
       try {
           while(rs.next()){
               ByteArrayInputStream in = new ByteArrayInputStream(rs.getBytes(1));
               ObjectInputStream is = new ObjectInputStream(in);
               Object retrieveDosBlob =(Object) is.readObject();
               if(retrieveDosBlob instanceof  ArrayList<?>){
                   DosageList=((ArrayList<DosageObject>) retrieveDosBlob);
               }
           }
       } catch (ClassNotFoundException e) {
   
           e.printStackTrace();
       } catch (IOException e) {
   
           e.printStackTrace();
       }
   
       // storing array list in an array list for future uses
   
       Vector<String> columnNames = new Vector<String>();
   
       columnNames.add("Description");
       columnNames.add("Prescription");
       columnNames.add("Medication Type");
       columnNames.add("Dosage");
       columnNames.add("Checked");
   
       Vector<Vector<Object>> data = new Vector<Vector<Object>>();
   
   
   
   
   
       for(int k=0;k<DosageList.size();k++){
           Vector<Object> vector = new Vector<Object>();
           vector.add(DosageList.get(k).getMedDescrip());
           vector.add(DosageList.get(k).getMedPrescrip());
           vector.add(DosageList.get(k).getMedType());
           vector.add(DosageList.get(k).getMedDosage());
   
           data.add(vector);
       }
   
   
       DefaultTableModel dtm = new DefaultTableModel(data, columnNames) {
           private static final long serialVersionUID = 4234183862785566645L;
   
           @Override
           public boolean isCellEditable(int rowIndex, int columnIndex) {
               return !( rowIndex == 1 && columnIndex == 1 );
           }
   
   
       };
       return dtm;
   }
   
   
   // Debug-able main method
   public static void main(String[] args) throws SQLException {
       ArrayList<String> nameList= new ArrayList<String>();
       nameList.add("Lee Ching Chong");
       nameList.add("Lim Kuay Siak");
       nameList.add("Lee Ching Chong");
   
       toDoTable =new JTable(getElderlyFromQueryDos("morning",nameList.get(0)));
   
   
       String[] values = new String[] { "Not Feed", "Feed" };
       TableColumn col = toDoTable.getColumnModel().getColumn(4);
       col.setCellEditor(new MyComboBoxEditor(values));
       col.setCellRenderer(new MyComboBoxRenderer(values));
   
       jpane = new JScrollPane(toDoTable);
       JPanel panel = new JPanel();
       JFrame frame = new JFrame();
       frame.setBounds(0, 0, 700, 543);
       panel.add(jpane);
       frame.getContentPane().add(new JScrollPane(panel));
   
       JButton btnNext = new JButton("Next");
       panel.add(btnNext);
       frame.setVisible(true);
       btnNext.addActionListener(new ActionListener() {
   
           public void actionPerformed(ActionEvent e) {
               try {
                   toDoTable.setModel(DosageTableHelper.getElderlyFromQueryDos("morning",nameList.get(counter)));
                   String[] values = new String[] { "Not Feed", "Feed" };
                   TableColumn col = toDoTable.getColumnModel().getColumn(4);
                   col.setCellEditor(new MyComboBoxEditor(values));
                   col.setCellRenderer(new MyComboBoxRenderer(values));
               } catch (SQLException e1) {
                   // TODO Auto-generated catch block
                   e1.printStackTrace();
               }
   
   
   
               counter++;
   
           }
   
       });
   
   }
   
   
   
   }
   @SuppressWarnings("rawtypes")
   class MyComboBoxRenderer extends JComboBox implements TableCellRenderer {
   
   private static final long serialVersionUID = 1319299961084034009L;
   
   @SuppressWarnings("unchecked")
   public MyComboBoxRenderer(String[] items) {
       super(items);
   }
   
   public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected,
           boolean hasFocus, int row, int column) {
       if (isSelected) {
           setForeground(table.getSelectionForeground());
           super.setBackground(table.getSelectionBackground());
       } else {
           setForeground(table.getForeground());
           setBackground(table.getBackground());
       }
       setSelectedItem(value);
       return this;
   }
   }
   class MyComboBoxEditor extends DefaultCellEditor {
   
   private static final long serialVersionUID = -1702063500403826596L;
   
   @SuppressWarnings({ "rawtypes", "unchecked" })
   public MyComboBoxEditor(String[] items) {
       super(new JComboBox(items));
   }
   }
   

示例输出:

Answer 1

1. 阅读 Oracle 教程 - How to use tables - part about to use JComboBox as TableCellEditor ,

   • 解释JTable有两个独立的功能TableCellEditor用于编辑存储在 XxxTableModel 中的值和TableCellRenderer用于绘制存储在 XxxTableModel 中的值,

   • 编辑后(事件、API 中实现的通知程序)，仅存储 TableCellEditor 中选定的值( JComboBox ) 到 XxxTableModel通过使用XxxTableModel.setValueAt ，存储"feed"或"not feed" ，不是JComboBox如Object , TableCellRenderer只是从模型到 View 进行绘制

   • 默认情况下，使用 DefaultTableModel 一切都会自动运行。 ，那么需要重写减少数量的方法( getColumnClass ， isCellEditeble ，在你的情况下 setValueAt 也可能)

2. 有两种方法(第一种需要覆盖 XxxTableModel.setValueAt )

   • JButton将被禁用(以编程方式)，直到所有值从空白更改为 "feed"或"not feed" ，需要在模型内循环，请在代码行 super.setValueAt() 之后注意执行后，编辑器中的值将存储到模型中

   • 来自 JButton 的操作模型内部循环(原始、最简单，但验证最有效，代码简单直接，XxxTableModel.setValueAt 内部没有错误)

3. 需要覆盖 XxxTableModel.setValueAt并设置、更改 isCellEditable(row, column)要正确的值，需要为 isCellEditable 创建单独的数组，仅对于模型事件，不要从外部更改此数组，只需方法 XxxTableModel.setValueAt可以是通知者

<小时/>

• 使用DefaultTableModel if 是可能的(以避免重写 AbstractTableModel 、方法、监听器，特别是模型通知程序所需的代码中的任何误解 - fireXxxXxx )

• 模型内部的代码顺序很重要，首先将值存储到模型中，然后调用任何更改、验证、附加代码，仅调用基于模型中存储的值的代码

• 我确信每三个点都会出现几次，包括 SSCCE/MCVE 表单中的工作代码示例