java - セルの値が同じ場合、JTable でセルの背景を変更する

Question

JTable について質問があります。

セルを選択し、選択した JTable に同じ値のセルがあると、そのセルは背景の赤い色を強調表示します。

どうすればいいのかわからない....

PS: 申し訳ありませんが、ここにコードを入力する方法がわかりません...;;

Answer 1

ListSelectionListenerテーブル内の選択の変更を追跡するために実装できます。TableCellRenderer次に、選択したオブジェクトと同じ値を持つセルの背景を変更する実装を行います。、レンダラー、および選択の詳細については、テーブルの使用方法を確認してください。JTable

以下は、この考え方を示す非常に単純な例です。

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;

import java.awt.Color;
import java.awt.Component;

public class TableDemo {
    private static void createAndShowGUI() {
        JFrame frame = new JFrame("TableDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel contentPanel = new JPanel();
        String[] columnNames = { "Column1", "Column2" };
        Object[][] data = { { "1", "3" }, { "2", "5" }, { "7", "1" },
                { "5", "3" } };

        JTable table = new JTable();
        MyModel model = new MyModel(Color.RED, table.getBackground());
        model.setDataVector(data, columnNames);

        table.setModel(model);
        table.setColumnSelectionAllowed(true);
        table.setDefaultRenderer(Object.class, new TestCellRenderer());

        SelectionListener listener = new SelectionListener(table);
        table.getSelectionModel().addListSelectionListener(listener);
        table.getColumnModel().getSelectionModel()
                .addListSelectionListener(listener);

        JScrollPane scrollPane = new JScrollPane(table);
        contentPanel.add(scrollPane);

        contentPanel.setOpaque(true);
        frame.add(contentPanel);

        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    static class TestCellRenderer extends DefaultTableCellRenderer {
        public Component getTableCellRendererComponent(JTable table,
                Object value, boolean isSelected, boolean hasFocus, int row,
                int column) {
            Component c = super.getTableCellRendererComponent(table, value,
                    isSelected, hasFocus, row, column);
            MyModel model = (MyModel) table.getModel();
            c.setBackground(model.getCellColor(row, column));
            return c;
        }
    }

    static class MyModel extends DefaultTableModel {
        private Object selectedObject;
        private Color selectedColor;
        private Color normalColor;

        public MyModel(Color selectedColor, Color normalColor) {
            this.selectedColor = selectedColor;
            this.normalColor = normalColor;
        }

        public Color getCellColor(int row, int column) {
            if (getValueAt(row, column).equals(selectedObject))
                return selectedColor;
            return normalColor;
        }

        public void setSelectedObject(Object selectedObject) {
            this.selectedObject = selectedObject;
            fireTableRowsUpdated(0, getRowCount());
        }
    }

    static class SelectionListener implements ListSelectionListener {
        private JTable table;

        SelectionListener(JTable table) {
            this.table = table;
        }

        public void valueChanged(ListSelectionEvent e) {
            int rowIndex = table.getSelectedRow();
            int colIndex = table.getSelectedColumn();
            if (!e.getValueIsAdjusting() && colIndex != -1 && rowIndex != -1) {
                ((MyModel) table.getModel()).setSelectedObject(table
                        .getValueAt(rowIndex, colIndex));
            }
        }
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

結果は次のとおりです。

EDIT：テーブルモデルなしで、レンダラーのみを使用したソリューション

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;

import java.awt.Color;
import java.awt.Component;

public class TableDemo {
    private static void createAndShowGUI() {
        JFrame frame = new JFrame("TableDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel contentPanel = new JPanel();
        String[] columnNames = { "Column1", "Column2" };
        Object[][] data = { { "1", "3" }, { "2", "5" }, { "7", "1" },
                { "5", "3" } };

        JTable table = new JTable(new DefaultTableModel(data, columnNames));
        table.setColumnSelectionAllowed(true);
        TestCellRenderer renderer = new TestCellRenderer();
        table.setDefaultRenderer(Object.class, renderer);

        SelectionListener listener = new SelectionListener(table);
        table.getSelectionModel().addListSelectionListener(listener);
        table.getColumnModel().getSelectionModel()
                .addListSelectionListener(listener);

        JScrollPane scrollPane = new JScrollPane(table);
        contentPanel.add(scrollPane);

        contentPanel.setOpaque(true);
        frame.add(contentPanel);

        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    static class TestCellRenderer extends DefaultTableCellRenderer {

        public Component getTableCellRendererComponent(JTable table, 
                Object value, boolean isSelected, boolean hasFocus, 
                int row, int column) {

            Component c = super.getTableCellRendererComponent(table, value,
                    isSelected, hasFocus, row, column);

            int columnIndex = table.getSelectedColumn();
            int rowIndex = table.getSelectedRow();

            if (columnIndex != -1 && rowIndex != -1){
                Object selectedValue = table.getValueAt(rowIndex, columnIndex);

                if (value.equals(selectedValue)) {
                    c.setBackground(Color.RED);
                } else {
                    c.setBackground(table.getBackground());
                }
            } 
            return c;
        }
    }

    static class SelectionListener implements ListSelectionListener {
        private JTable table;

        SelectionListener(JTable table) {
            this.table = table;
        }

        public void valueChanged(ListSelectionEvent e) {
            int rowIndex = table.getSelectedRow();
            int colIndex = table.getSelectedColumn();

            if (!e.getValueIsAdjusting() && colIndex != -1 && rowIndex != -1){
                table.repaint();
            }
        }
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}