我想通过输入行号和列号来为JTable上的特定单元着色。
例如，我有这个代码，意味着为第一个单元格着色= 0，列= 0，但它不起作用
package functions_classes;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.border.LineBorder;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.table.*;
public class RemoveAddRows extends JFrame {
static DefaultTableCellRenderer stringRenderer;
static Component c;
private static final long serialVersionUID = 1L;
private Object[] columnNames = {"Type", "Company", "Shares", "Price"};
private Object[][] data = {
{"Buy", "IBM", Integer.valueOf(1000), Double.valueOf(80.50)},
{"Sell", "MicroSoft", Integer.valueOf(2000), Double.valueOf(6.25)},
{"Sell", "Apple", Integer.valueOf(3000), Double.valueOf(7.35)},
{"Buy", "Nortel", Integer.valueOf(4000), Double.valueOf(20.00)}
};
public static JTable table;
private DefaultTableModel model;
private javax.swing.Timer timer = null;
public RemoveAddRows() {
model = new DefaultTableModel(data, columnNames) {
private static final long serialVersionUID = 1L;
@Override
public Class getColumnClass(int column) {
return getValueAt(0, column).getClass();
}
};
table = new JTable(model) {
private static final long serialVersionUID = 1L;
@Override
public Component prepareRenderer(TableCellRenderer renderer, int row, int column) {
c = super.prepareRenderer(renderer, row, column);
System.out.println("la valeur de row egale "+row);
System.out.println("la valeur de column egale "+column);
if (isRowSelected(0) && isColumnSelected(0)) {
// ((JComponent) c).setBorder(new LineBorder(Color.red));
((JComponent) c).setBackground(Color.RED);
}
return c;
}
};
stringRenderer = (DefaultTableCellRenderer) table.getDefaultRenderer(String.class);
stringRenderer.setHorizontalAlignment(SwingConstants.CENTER);
ListSelectionModel rowSelMod = table.getSelectionModel();
rowSelMod.addListSelectionListener(new ListSelectionListener() {
@Override
public void valueChanged(ListSelectionEvent e) {
int row = table.getSelectedRow();
int col = table.getSelectedColumn();
String str = "Selected Row(s): ";
int[] rows = table.getSelectedRows();
for (int i = 0; i < rows.length; i++) {
str += rows[i] + " ";
}
str += "Selected Column(s): ";
int[] cols = table.getSelectedColumns();
for (int i = 0; i < cols.length; i++) {
str += cols[i] + " ";
}
str += "Selected Cell: " + table.getSelectedRow() + ", " + table.getSelectedColumn();
System.out.println(str);
Object value = table.getValueAt(row, col);
System.out.println(String.valueOf(value));
}
});
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
JButton button1 = new JButton("Remove all rows");
button1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
if (model.getRowCount() > 0) {
for (int i = model.getRowCount() - 1; i > -1; i--) {
model.removeRow(i);
}
}
System.out.println("model.getRowCount() --->" + model.getRowCount());
}
});
JButton button2 = new JButton("Add new rows");
button2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
start();
}
});
JPanel southPanel = new JPanel();
southPanel.add(button1);
southPanel.add(button2);
add(southPanel, BorderLayout.SOUTH);
}
private void start() {
timer = new javax.swing.Timer(2500, updateCol());
timer.start();
}
public Action updateCol() {
return new AbstractAction("text load action") {
private static final long serialVersionUID = 1L;
@Override
public void actionPerformed(ActionEvent e) {
DefaultTableModel model = (DefaultTableModel) table.getModel();
Object[] data0 = {"Buy", "IBM", Integer.valueOf(1000), Double.valueOf(80.50)};
model.addRow(data0);
Object[] data1 = {"Sell", "MicroSoft", Integer.valueOf(2000), Double.valueOf(6.25)};
model.addRow(data1);
Object[] data2 = {"Sell", "Apple", Integer.valueOf(3000), Double.valueOf(7.35)};
model.addRow(data2);
Object[] data3 = {"Buy", "Nortel", Integer.valueOf(4000), Double.valueOf(20.00)};
model.addRow(data3);
System.out.println("model.getRowCount() --->" + model.getRowCount());
timer.stop();
int rowIndex = table.getRowCount() - 1;
table.changeSelection(rowIndex, 0, false, false);
}
};
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
RemoveAddRows frame = new RemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
// table.prepareRenderer(stringRenderer, 1, 2);
//Component c1=table.prepareRenderer((DefaultTableCellRenderer) table.getDefaultRenderer(String.class), 1,1);
// stringRenderer = (DefaultTableCellRenderer) table.getDefaultRenderer(String.class);
// JComponent c1=(JComponent) table.prepareRenderer(stringRenderer, 0,0);
// c1.setBackground(Color.cyan);
}
});
}
}
答案 0 :(得分：4)
您需要实现自定义单元格渲染器才能执行此操作，我已经修改了一些旧代码。希望这应该有效，我已经检查过它编译，但我没有测试过它;
import javax.swing.JTable;
import javax.swing.table.DefaultTableCellRenderer;
import java.awt.Component;
import java.awt.Color;
import java.util.HashMap;
public class ColorCellRenderer extends DefaultTableCellRenderer {
class Coordinate
{
public int row, col;
public Coordinate(int row, int col)
{
this.row=row;this.col=col;
}
@Override
public boolean equals(Object o)
{
if(o instanceof Coordinate)
{
return (((Coordinate)o).row==this.row)&&(((Coordinate)o).col==this.col);
}
return false;
}
@Override
public int hashCode()
{//Unique until col 10000
return col + row*10000;
}
}
private HashMap<Coordinate, Color> colorMap;
public ColorCellRenderer() {
super();
colorMap = new HashMap<Coordinate, Color>();
}
public Color setColor(int row, int col, Color c)
{
return colorMap.put(new Coordinate(row, col), c);
}
/**
* Returns the component used for drawing the cell. This method is
* used to configure the renderer appropriately before drawing.
*
* @param table - JTable object
* @param value - the value of the cell to be rendered.
* @param isSelected - isSelected true if the cell is to be rendered with the selection highlighted;
* otherwise false.
* @param hasFocus - if true, render cell appropriately.
* @param row - The row index of the cell being drawn.
* @param column - The column index of the cell being drawn.
* @return - Returns the component used for drawing the cell.
*/
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);
//Get color from nested hashmap
//We allow it to setBackground(null) as DefaultRenderer doesn't resetBackground when called again.
if(isSelected){
c.setBackgroun(table.getSelectionBackground());
}else{
c.setBackground(colorMap.get(new Coordinate(row, column)));
}
return c;
}
}
答案 1 :(得分：2)
而不是：
if (isRowSelected(0) && isColumnSelected(0)) {
// ((JComponent) c).setBorder(new LineBorder(Color.red));
((JComponent) c).setBackground(Color.RED);
}
使用这段代码：
c.setBackground((row == 0) && (column == 0) ? Color.RED : Color.WHITE);
答案 2 :(得分：-1)
JComponent不知道如何设置背景。
相反，您应该手动在组件上绘制颜色。
我建议您创建自己的组件：
private class CustomComponent extends JComponent{
CustomComponent() {
setBackground(Color.BLACK);
}
public void paintComponent(Graphics g) {
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
}
}
您可以在自定义组件中进行isSelected验证，并相应地设置颜色。