刪除行從JTable中自定義表格模型

Question

我一直的JTable一個子類，使用自定義表模型（的AbstractTableModel實現）來管理數據。

的問題，當我試圖刪除一行與方法deleteRow發生。我的表中的行被替換爲空白字符串，但行未被刪除。

下面是代碼：

public class LiveSearchTableModel extends AbstractTableModel 
{ 

    private List<String> columnNames = new ArrayList<String>(); 
    private Map<Point, Object> displayData = new HashMap<Point, Object>(); 
    private Map<Point, Object> originalData = new HashMap<Point, Object>(); 

    public LiveSearchTableModel(List<String> columnNames, 
     Map<Point, Object> tableData) 
    { 
    this.columnNames = columnNames; 
    this.displayData = tableData; 
    this.originalData.putAll(tableData); 
    } 

    @Override 
    public int getColumnCount() { 
    return columnNames.size(); 
    } 

    @Override 
    public int getRowCount() { 
    return displayData.size()/columnNames.size(); 
    } 

    @Override 
    public Object getValueAt(int rowIndex, int columnIndex) { 
    return displayData.get(new Point(rowIndex, columnIndex)); 
    } 

    public void deleteRow (int row) 
    { 
    for (int cont = 0; cont < columnNames.size();cont++) 
    { 
     displayData.remove(new Point (row,cont)); 
    } 

    this.fireTableRowsDeleted(row, row); 
    } 

    @Override 
    public void setValueAt(Object value, int rowIndex, int columnIndex) 
    { 
    this.displayData.put(new Point(rowIndex, columnIndex), value); 
    this.fireTableDataChanged(); 
    } 
} 

Answer 1

的sscce下面示出了一個潛在的問題：一個Map的鍵是不排序，而表的行是。在所示的方法中，必須通過對數據的每次更改來更新密鑰數組。另請參閱此相關的example。如果需要，你可以擴展Point實施Comparable，爲Value所示here。

import java.awt.BorderLayout; 
import java.awt.EventQueue; 
import java.awt.Point; 
import java.awt.event.ActionEvent; 
import java.util.ArrayList; 
import java.util.Arrays; 
import java.util.HashMap; 
import java.util.List; 
import java.util.Map; 
import javax.swing.AbstractAction; 
import javax.swing.JButton; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.JTable; 
import javax.swing.table.AbstractTableModel; 

/** 
* @see https://stackoverflow.com/q/12330167/230513 
*/ 
public class TableModelTest extends JPanel { 

    public TableModelTest() { 
     super(new BorderLayout()); 
     final MyModel model = new MyModel(); 
     JTable table = new JTable(model); 
     this.add(new JScrollPane(table)); 
     this.add(new JButton(new AbstractAction("Delete") { 

      @Override 
      public void actionPerformed(ActionEvent e) { 
       model.remove(0); 
      } 
     }), BorderLayout.SOUTH); 
    } 

    public class MyModel extends AbstractTableModel { 

     private List<String> names = new ArrayList<String>(); 
     private Map<Point, Object> data = new HashMap<Point, Object>(); 
     private Point[] keys; 

     public MyModel() { 
      this.names = Arrays.asList("Point", "Name"); 
      data.put(new Point(1, 1), "One"); 
      data.put(new Point(2, 2), "Two"); 
      data.put(new Point(3, 3), "Three"); 
      this.keys = data.keySet().toArray(new Point[data.size()]); 
     } 

     public void remove(int row) { 
      data.remove(keys[row]); 
      keys = data.keySet().toArray(new Point[data.size()]); 
      this.fireTableRowsDeleted(row, row); 
     } 

     @Override 
     public int getColumnCount() { 
      return names.size(); 
     } 

     @Override 
     public String getColumnName(int col) { 
      return names.get(col); 
     } 

     @Override 
     public int getRowCount() { 
      return data.size(); 
     } 

     @Override 
     public Object getValueAt(int row, int col) { 
      if (col == 0) { 
       return keys[row]; 
      } else { 
       return data.get(keys[row]); 
      } 
     } 
    } 

    private void display() { 
     JFrame f = new JFrame("TableModelTest"); 
     f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     f.add(this); 
     f.pack(); 
     f.setLocationRelativeTo(null); 
     f.setVisible(true); 
    } 

    public static void main(String[] args) { 
     EventQueue.invokeLater(new Runnable() { 

      @Override 
      public void run() { 
       new TableModelTest().display(); 
      } 
     }); 
    } 
}