java - 为什么 JTable 不显示 DefaultTableModel 中存储的任何数据？

Question

这是我的 Controller (从模型读取数据并将这些数据分配给类 View 中的 JTable 对象和 MedalTableModel 对象):

public class TableController { 

    private TableModel table_model;
    private TableView table_view;

    public TableController (TableModel table_model, TableView table_view) {            
        this.table_model = table_model;
        this.table_view = table_view;
    }

    public void getMedalData () {
        try {
            table_model.getCsvData();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void setFilePath (String file_path) {
        table_model.setFilePath(file_path);
    }
    /*
    public void addLineData (ArrayList<String> data_list) {     
        Object[] line_data = new Object[data_list.size()];          
        for (int index = 0; index < data_list.size(); index ++) {
            line_data[index] = data_list.get(index);
        }            
        table_view.getTableModel().addRow(line_data);
    }
    */
    public void addTableData (String file_path) {            
        Object[] col_names = {"Country name", "Official medal ranking",
                "GDP rank", "Pop rank", "Team size"};            
        setFilePath(file_path);
        getMedalData();            
        int row_size = table_model.getRowSize();
        int col_size = table_model.getColumnSize();
        Object[][] table_data = new Object[row_size][col_size];            
        ArrayList<String> data_list = new ArrayList<String>();          
        for (int row_index = 0; row_index < row_size; row_index ++) {               
            data_list = table_model.getLineData(row_index);
            for (int col_index = 0; col_index < col_size; col_index ++) {                   
                table_data[row_index][col_index] = data_list.get(col_index);          
            }
        }           
        //table_view.setTableData(table_data);
        JTable temp_table = new JTable (table_data, col_names);
        table_view.setTable(temp_table);
        MedalTableModel temp_model = new MedalTableModel(table_data, col_names);
        table_view.setTableModel(temp_model);    
    }        
}

这是我的观点:

public class TableView extends JFrame{

    //private DefaultTableModel def_model;
    private MedalTableModel mtable_model;
    private JTable medal_table;
    private JButton close_button;
    private TableRowSorter sorter;
    private Object[][] table_data;

    /*
    public DefaultTableModel getTableModel () {
        return def_model;
    }

    // maybe do not need this method
    public void setTableModel (DefaultTableModel table_model) {
        this.def_model = table_model;
    }
    */
    public TableView(String frame_title) {
        super(frame_title);         
        medal_table = new JTable();         
        JScrollPane scroll = new JScrollPane(medal_table);          
        JPanel button_panel = new JPanel();
        close_button = new JButton("Close");      
        button_panel.add(close_button);
        getContentPane().add(scroll, BorderLayout.CENTER);
        getContentPane().add(button_panel, BorderLayout.SOUTH);
        pack();         
    }

    public void setTableData (Object[][] table_data) {
        this.table_data = table_data;
    }

    public Object[][] getTabledata () {
        return table_data;
    }

    public MedalTableModel getTableModel () {
        return mtable_model;
    }

    // maybe do not need this method
    public void setTableModel (MedalTableModel table_model) {
        this.mtable_model = table_model;
    }

    public void setTable (JTable table) {
        this.medal_table = table;
    }

    public void setTableModel () {
        //add data here
        medal_table.setModel(mtable_model);
    }

    // set sort feature should be added after setModel
    public void setSortMtd () {         
        //sorter = new TableRowSorter<DefaultTableModel>(def_model);            
         medal_table.setAutoCreateRowSorter(false);         
         TableRowSorter trs = new TableRowSorter(mtable_model);    
         class IntComparator implements Comparator {
             public int compare(Object o1, Object o2) {
                 Integer int1 = (Integer)o1;
                 Integer int2 = (Integer)o2;
                 return int1.compareTo(int2);
             }

             public boolean equals(Object o2) {
                 return this.equals(o2);
             }
         }    
         trs.setComparator(1, new IntComparator());
         trs.setComparator(2, new IntComparator());             
         medal_table.setRowSorter(trs);             
         medal_table.setModel(mtable_model);
    }
}

这是我的 MedalTableModel 扩展了 DefaultTableModel；

public class MedalTableModel extends DefaultTableModel {
    public MedalTableModel (Object[][] table_data, Object[] col_names) {
        super(table_data, col_names);
    }
        public MedalTableModel() {
        // TODO Auto-generated constructor stub
    }

    Class[] types = { String.class, Integer.class, Integer.class,
            Integer.class, Integer.class };

    //String[] ColumnName = {"Country name", "Official medal ranking",
    //        "GDP rank", "Pop rank", "Team size"};

    @Override
    public Class getColumnClass (int columnIndex) {
        return this.types[columnIndex];
    }

    /*
    @Override
    public String getColumnName(int index) {
        return ColumnName[index];
    }
    */
    /*
    @Override  
    public Class getColumnClass(int col) {  

        //zero column accepts only String values
        if (col > 0) {
            return Integer.class;   
        }       
        else {
            return String.class; 
        }
    }  
    */
    @Override  
    public boolean isCellEditable(int row, int col) {  

        return false;  
    }  
}

这是主要方法(在​​另一个文件中):(初始模型、 Controller 和 View )

public static void main( String[] args ) {

    SwingUtilities.invokeLater(new Runnable() {

        public void run () {                
            String file_path = "London2012OlympicAlternativeMedalRankingsALL.csv";
            TableModel table_model = new TableModel(file_path);
            TableView table_view = new TableView("Medal Table");    
            TableController table_contrl = new TableController(table_model,
                    table_view);
            table_contrl.addTableData(file_path);               
            table_view.setSortMtd();
            table_view.setVisible(true);
            table_view.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    
        }
    });         
    //System.out.println( "Hello World!" );
}

问题是，当我尝试运行该程序时，它在 JFrame 中没有显示任何内容。我的代码有什么问题？非常感谢。

Answer 1

您从未真正在 JTable 上设置 TableModel。您有一个似乎没有必要的变量，这可能就是为什么您没有在 JTable 对象上设置它并不明显的原因。

看起来你有一个设置它的方法:

public void setTableModel () {
    //add data here
    medal_table.setModel(mtable_model);
}

但该方法从未被调用。