在java中设置jtable中下一列的数据

Question

大家好。我只想问，如何设置下一列值的值？在这里，我有一个计数器“计数器”，它在 sampleTable 中添加了真正的布尔值的数量。我想要做的是为“总计”设置表格下一列中数据的值。 “总”数据应该是计数器值。我该怎么办？

private void tableTest(){
    int nRow = sampleTable.getRowCount();
    int nCol = sampleTable.getColumnCount();
    int counter = 0;

    Object[][] tableData = new Object[nRow][nCol];
    for (int i = 0 ; i < nRow ; i++){
        for (int j = 3 ; j < nCol ; j++){
            tableData[i][j] = sampleTable.getValueAt(i,j);
            System.out.println(tableData[i][j]);
            if(tableData[i][j] != null && tableData[i][j].equals(true)){
                counter++;
            }
        }
      /* if(nCol == 7){
                sampleTable.setValueAt(i, 7, counter);
            }else{
                tableData = new Object[nRow][nCol + 1];
                sampleTable.setValueAt(i, 7, counter);
            }*/
       System.out.println(counter);
       sampleTable.setValueAt(i,7,counter);
       counter = 0;
    }
}

Answer 1

如果没有更多内容，就不可能知道 1. 你想要做什么以及 2. 你可能做错了什么......

下面的例子真的很简单。它的作用是让您更改表格，然后点击“更新”按钮，然后通过并计算每一行的总数...

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.AbstractTableModel;

public class TallyTableTest {

    public static void main(String[] args) {
        new TallyTableTest();
    }

    public TallyTableTest() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                try {
                    final MyTableModel model = new MyTableModel();
                    loadData(model);
                    JTable table = new JTable(model);

                    JButton update = new JButton("Update");
                    update.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            for (int row = 0; row < model.getRowCount(); row++) {
                                int counter = 0;
                                for (int col = 3; col < 7; col++) {
                                    Object value = model.getValueAt(row, col);
                                    if (value instanceof Boolean && (boolean)value) {
                                        counter++;
                                    }
                                }
                                model.setValueAt(counter, row, 7);
                            }
                        }
                    });

                    JFrame frame = new JFrame("Testing");
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.setLayout(new BorderLayout());
                    frame.add(new JScrollPane(table));
                    frame.add(update, BorderLayout.SOUTH);
                    frame.pack();
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);


                } catch (IOException exp) {
                    exp.printStackTrace();
                }
            }
        });

    }

    public void loadData(MyTableModel model) throws IOException {
        // Fill your model here
    }

    public static class MyTableModel extends AbstractTableModel {

        protected static final String[] COLUMNS = new String[]{
            "ID", "First Name", "Last Name", "1", "2", "3", "4", "total"
        };
        protected static final Class[] COLUMN_TYPES = new Class[]{
            Integer.class, String.class, String.class,
            Boolean.class, Boolean.class, Boolean.class, Boolean.class,
            Integer.class
        };
        private List<Object[]> rows;

        public MyTableModel() {
            rows = new ArrayList<>(25);
        }

        public void addRow(Object[] data) {
            rows.add(data);
        }

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

        @Override
        public int getColumnCount() {
            return COLUMNS.length;
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return COLUMN_TYPES[columnIndex];
        }

        @Override
        public String getColumnName(int column) {
            return COLUMNS[column];
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            Object[] row = rows.get(rowIndex);
            return row[columnIndex];
        }

        @Override
        public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
            Object[] row = rows.get(rowIndex);
            row[columnIndex] = aValue;
            fireTableCellUpdated(rowIndex, columnIndex);
        }

        @Override
        public boolean isCellEditable(int rowIndex, int columnIndex) {
            return columnIndex >= 3 && columnIndex <= 6;
        }
    }

}

该示例的作用是实时更新总数。这意味着，每次更改行的列值时，它都会重新计算行总数并在内部更新模型。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.AbstractTableModel;

public class TallyTableTest {

    public static void main(String[] args) {
        new TallyTableTest();
    }

    public TallyTableTest() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                try {
                    final MyTableModel model = new MyTableModel();
                    loadData(model);
                    JTable table = new JTable(model);

                    JFrame frame = new JFrame("Testing");
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.setLayout(new BorderLayout());
                    frame.add(new JScrollPane(table));
                    frame.pack();
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);

                } catch (IOException exp) {
                    exp.printStackTrace();
                }
            }
        });

    }

    public void loadData(MyTableModel model) throws IOException {
        // Fill your model here...
    }

    public static class MyTableModel extends AbstractTableModel {

        protected static final String[] COLUMNS = new String[]{
            "ID", "First Name", "Last Name", "1", "2", "3", "4", "total"
        };
        protected static final Class[] COLUMN_TYPES = new Class[]{
            Integer.class, String.class, String.class,
            Boolean.class, Boolean.class, Boolean.class, Boolean.class,
            Integer.class
        };
        private List<Object[]> rows;

        public MyTableModel() {
            rows = new ArrayList<>(25);
        }

        public void addRow(Object[] data) {
            rows.add(data);
        }

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

        @Override
        public int getColumnCount() {
            return COLUMNS.length;
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return COLUMN_TYPES[columnIndex];
        }

        @Override
        public String getColumnName(int column) {
            return COLUMNS[column];
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            Object[] row = rows.get(rowIndex);
            return row[columnIndex];
        }

        @Override
        public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
            Object[] row = rows.get(rowIndex);
            row[columnIndex] = aValue;

            int counter = 0;
            for (int col = 3; col < 7; col++) {
                Object value = row[col];
                if (value instanceof Boolean && (boolean) value) {
                    counter++;
                }
            }
            row[7] = counter;
            fireTableCellUpdated(rowIndex, columnIndex);
            fireTableCellUpdated(rowIndex, 7);
        }

        @Override
        public boolean isCellEditable(int rowIndex, int columnIndex) {
            return columnIndex >= 3 && columnIndex <= 6;
        }
    }

}