我不能让我的JTable显示任何东西 [英] I can't get my JTable to show anything

问题描述

我不能让我的gui显示Jtable，为什么我不知道，我没有得到任何错误，当我打印一些东西到屏幕上我得到9列。所以我得到了数据。但是我做错了我不知道。

I cant get my gui to show the Jtable, why i dont know and i dont get any error and when i print something to the screen i get 9 colum. so i get data. but what i'm doing wrong i have no idea about that.

我的GUIOdreHandler看起来像这样

My GUIOdreHandler looks like this

public GUIOrdreHandler(){

            KaldSQL ks = new KaldSQL();
            ResultSet rs;

        }

        public static DefaultTableModel buildTableModel(ResultSet rs)
                throws SQLException {

            java.sql.ResultSetMetaData metaData = rs.getMetaData();

            // names of columns
            Vector<String> columnNames = new Vector<String>();
            int columnCount = metaData.getColumnCount();
            for (int column = 1; column <= columnCount; column++) {
                columnNames.add(metaData.getColumnName(column));
                System.out.println(columnCount);
            }

            // data of the table
            Vector<Vector<Object>> data = new Vector<Vector<Object>>();
            while (rs.next()) {
                Vector<Object> vector = new Vector<Object>();
                for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
                    vector.add(rs.getObject(columnIndex));
                }
                data.add(vector);
            }

            return new DefaultTableModel(data, columnNames);

            }

我的GUIHentOrdre看起来像这样

And my GUIHentOrdre looks like this

public GUIHentOrdre(){

        try {
            con = ks.connectNow();
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }


        JPanel info = new JPanel();
        info.setLayout(new BorderLayout());
        button = new JButton("button");
        info.add(button, BorderLayout.CENTER);
        add(button);
        ResultSet rs = ks.Hentalleordreliste(con);
        GUIOrdreHandler gh = new GUIOrdreHandler();

        try {
            table = new JTable(gh.buildTableModel(rs));

            System.out.println(table);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        info.add(table, BorderLayout.CENTER);
        add(table);
    }
}

我试过了什么谷歌，预订北方工作，所以请帮助我
：D

I have tried anything google, book northing works, so please help me :D

推荐答案

关于代码中的错误

JPanel info = new JPanel();
info.setLayout(new BorderLayout());
button = new JButton("button");
info.add(button, BorderLayout.CENTER);
add(button);

• 删除关于的代码行添加（按钮）; 到（代码不完全在谈论）

  • remove code line about add(button); to the (code not exactly talking about)

    更改 info.add（按钮） ，BorderLayout.CENTER）; 到 NORTH 或 SOUTH

    您没有将 JTable （在 JScrollPane 中）添加到 JPanel 正确

    you not added JTable (in JScrollPane) to the JPanel correctly

    伪代码

    JPanel info = new JPanel();
    info.setLayout(new BorderLayout());
    button = new JButton("button");
    info.add(button, BorderLayout.SOUTH);
    JTable table = new JTable (ClassOrVoidOrModelNameReturnsTableModel)
    JScrollPane scroll = new JScrollPane(table)
    info.add(scroll, BorderLayout.CENTER);
    

    
    
    

    
    

    • 但上面没什么好解决的，因为你的问题应该是一些例外来自 JDBC

      
      

      1. 不要创建 JComponent s里面尝试 - catch 阻止，准备这个对象之前，更好的可能是本地变量

      1. don't to create JComponents inside try - catch block, prepare this Object before, better could be as local variable

      不要在里面 JComponent 创建 XxxModel 试试 - catch 阻止，准备此对象之前，更好的可能是本地变量

      don't to create XxxModel for JComponents inside try - catch block, prepare this Object before, better could be as local variable

      初始化 XxxModel 及其 JComponent ，然后将数据从 JDBC 加载到 XxxModel

      intialize XxxModel and its JComponent, then to load data from JDBC to the XxxModel

      将 rs.close（）添加到 finally 块（尝试 - catch - 最后）

      add rs.close() to the finally block (try - catch - finally)

    
    

    • 不要重新发明轮子，请使用

    • don't reinvent the wheel, use

      
      

      1. ResultSetTableModel

      来自@camickr的数据库表

      Table From Database by @camickr

    
    

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