我希望我的 JTable 的列标题在它们的值是表的 rowFilter 的基础时在它们的左侧获得一个额外的图标。排序图标显示在右侧，因此将两个图标“粘合”为一个不算数(尽管我也无法使 Nimbus 正常工作......)。我已经尝试了几个关于渲染器的想法，但我做不到……“方法”的描述以及它们的问题包含在发布的代码中。
编辑:忘记了一个简单的 setIcon - 在这种情况下，问题出在排序图标上。使排序图标可见会隐藏其他图标。
编辑:这个Nimbus TableHeader was not highlighted as 'pressed'给出了如何通过下面的第三次尝试(使用模型背景图像的尝试)解决问题的想法。但我不知道如何知道 MouseOver、Focused 等的值……如何将它们作为 boolean 值获取？ (我的意思是 mouseOver 状态的 true/false，聚焦状态的 tru/false 等等，这样我就可以准备一个模型图像的查找表，并为列标题的当前状态获取正确的图像)...
编辑:要查看三种情况中每一种情况的输出，您必须使用所需的渲染器类修改 table.getTableHeader().setDefaultRenderer(new FilterIconHeaderRenderer3(table)); 行。
I've tried to show the problems with the three attempts on this image
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableRowSorter;
public class TableHeaderTest extends JFrame {
JTable table = new JTable(new DefaultTableModel(new Object[]{"Column1", "Column2", "Column3"}, 3));
TableHeaderTest() {
TableRowSorter sorter = new TableRowSorter(table.getModel());
table.setRowSorter(sorter);
table.getTableHeader().setDefaultRenderer(new FilterIconHeaderRenderer3(table));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setViewportView(table);
add(scrollPane, BorderLayout.CENTER);
pack();
setVisible(true);
}
public static void main(String[] args) {
try {
UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
} catch (UnsupportedLookAndFeelException | ClassNotFoundException | IllegalAccessException | InstantiationException ex) {
System.out.println("[L&F][Exception] " + ex.getMessage());
}
EventQueue.invokeLater(() -> {
new TableHeaderTest();
});
}
}
/**
* Trying to copy the look of a TableHeader and override its paintComponent
* method for drawing the additional icon. However the look can't be entirely
* copied and for example the sorting icon and background behave differently.
* Also the indent of column name dissapeared.
*/
class FilterIconHeaderRenderer1 implements TableCellRenderer {
TableCellRenderer delegate;
ImageIcon filterIcon = new ImageIcon(getClass().getResource("/res/marker-dot-green.png"));
public FilterIconHeaderRenderer1(JTable table) {
this.delegate = table.getTableHeader().getDefaultRenderer();
}
@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
Component c = delegate.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
if (c instanceof JLabel) {
JLabelCopy label = new JLabelCopy((JLabel) c);
return label;
}
return c;
}
class JLabelCopy extends JLabel {
boolean withIcon = true;
JLabelCopy(JLabel label) {
this.ui = label.getUI();
this.setText(label.getText());
this.setPreferredSize(label.getPreferredSize());
this.setVerticalTextPosition(label.getVerticalTextPosition());
this.setHorizontalTextPosition(label.getHorizontalTextPosition());
this.setVerticalAlignment(label.getVerticalAlignment());
this.setHorizontalAlignment(label.getHorizontalAlignment());
this.setIcon(label.getIcon());
this.setIconTextGap(label.getIconTextGap());
this.setAlignmentX(label.getAlignmentX());
this.setAlignmentY(label.getAlignmentY());
this.setLayout(label.getLayout());
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (withIcon) {
g.drawImage(filterIcon.getImage(), 4, 4, null);
}
}
}
}
/**
* Also trying to copy the look of a TableHeader but without overriding its
* paintComponent method. Instead I make the header a panel consiting of two
* jLabels - the original column header and a jlabel of copied look with added
* icon. Problem with this method is theseparator of the visible separator of
* the two labels and the color difference of when a column is sorted (the
* copied-look-label doesn't change it's background to match a sorted header).
*
*/
class FilterIconHeaderRenderer2 implements TableCellRenderer {
TableCellRenderer delegate;
ImageIcon filterIcon = new ImageIcon(getClass().getResource("/res/marker-dot-green.png"));
public FilterIconHeaderRenderer2(JTable table) {
this.delegate = table.getTableHeader().getDefaultRenderer();
}
@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
JPanel newHeader = new JPanel(new BorderLayout());
Component c = delegate.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
if (c instanceof JLabel) {
JLabel label = (JLabel) c;
JLabelCopy filterIconLabel = new JLabelCopy(label);
filterIconLabel.setText("");
filterIconLabel.setIcon(filterIcon);
filterIconLabel.setPreferredSize(new Dimension(filterIcon.getIconWidth() + 4, filterIconLabel.getPreferredSize().height));
newHeader.add(filterIconLabel, BorderLayout.WEST);
newHeader.add(label, BorderLayout.CENTER);
return newHeader;
}
return c;
}
class JLabelCopy extends JLabel {
boolean withIcon = true;
JLabelCopy(JLabel label) {
this.ui = label.getUI();
this.setPreferredSize(label.getPreferredSize());
this.setVerticalTextPosition(label.getVerticalTextPosition());
this.setHorizontalTextPosition(label.getHorizontalTextPosition());
this.setVerticalAlignment(label.getVerticalAlignment());
this.setHorizontalAlignment(label.getHorizontalAlignment());
this.setIcon(label.getIcon());
this.setIconTextGap(label.getIconTextGap());
this.setAlignmentX(label.getAlignmentX());
this.setAlignmentY(label.getAlignmentY());
this.setLayout(label.getLayout());
}
}
}
/**
* Having an array of header mockups for each state for selected and hasFocus
* (lacks sorted state) of the column header. Using these as background of panel
* loaded with two labels - original header and label with just the new icon.
* Both have setOpaque(false). Problem with this is the problem with choosing
* the right background image for the panel as the isSelected and hasFocus
* parameters of getRendererComponent don't work as you think they should.
*/
class FilterIconHeaderRenderer3 implements TableCellRenderer {
private BufferedImage[][] headerImages = new BufferedImage[2][2];
TableCellRenderer delegate;
ImageIcon filterIcon = new ImageIcon(getClass().getResource("/res/marker-dot-green.png"));
public FilterIconHeaderRenderer3(JTable table) {
this.delegate = table.getTableHeader().getDefaultRenderer();
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 2; j++) {
JLabel comp = (JLabel) delegate.getTableCellRendererComponent(table, " ", i == 1, j == 1, 0, 0);
headerImages[i][j] = createUMPFake(comp);
}
}
}
@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
Component c = delegate.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
if (c instanceof JLabel) {
JPanel newHeader = new JPanel(new BorderLayout()) {
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(headerImages[isSelected ? 1 : 0][hasFocus ? 1 : 0], 0, 0, null);
}
};
JLabel label = (JLabel) c;
label.setOpaque(false);
JLabel filterIconLabel = new JLabel();
filterIconLabel.setText("");
filterIconLabel.setOpaque(false);
filterIconLabel.setIcon(filterIcon);
filterIconLabel.setPreferredSize(new Dimension(filterIcon.getIconWidth() + 4, filterIconLabel.getPreferredSize().height));
newHeader.add(filterIconLabel, BorderLayout.WEST);
newHeader.add(label, BorderLayout.CENTER);
return newHeader;
}
return c;
}
/*
* Following methods were taken from:
* https://stackoverflow.com/questions/4028898/create-an-image-from-a-non-visible-awt-component
*/
private BufferedImage createUMPFake(Component comp) {
JFrame invisibleFrame = new JFrame();
invisibleFrame.setSize(comp.getPreferredSize());
JPanel colorPanel = new JPanel();
colorPanel.setOpaque(false);
colorPanel.setLayout(new BorderLayout());
colorPanel.setBackground(new Color(0, 0, 255, 0));
colorPanel.setSize(invisibleFrame.getSize());
colorPanel.add(comp, BorderLayout.CENTER);
invisibleFrame.add(colorPanel);
colorPanel.setVisible(true);
return createImage((JComponent) colorPanel, new Rectangle(invisibleFrame.getBounds()));
}
/**
* Create a BufferedImage for Swing components. All or part of the component
* can be captured to an image.
*
* @param component component to create image from
* @param region The region of the component to be captured to an image
* @return image the image for the given region
*/
private static BufferedImage createImage(Component component, Rectangle region) {
// Make sure the component has a size and has been layed out.
// (necessary check for components not added to a realized frame)
if (!component.isDisplayable()) {
Dimension d = component.getSize();
if (d.width == 0 || d.height == 0) {
d = component.getPreferredSize();
component.setSize(d);
}
layoutComponent(component);
}
BufferedImage image = new BufferedImage(region.width, region.height, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = image.createGraphics();
// Paint a background for non-opaque components,
// otherwise the background will be black
if (!component.isOpaque()) {
g2d.setColor(component.getBackground());
g2d.fillRect(region.x, region.y, region.width, region.height);
}
g2d.translate(-region.x, -region.y);
component.paint(g2d);
g2d.dispose();
return image;
}
private static void layoutComponent(Component component) {
synchronized (component.getTreeLock()) {
component.doLayout();
if (component instanceof Container) {
for (Component child : ((Container) component).getComponents()) {
layoutComponent(child);
}
}
}
}
}
最佳答案
或者更简单，您可以使用 HTML 标记在 HeaderRenderer 上显示图标:
import java.awt.*;
import java.awt.event.*;
import java.net.URL;
import java.util.Objects;
import javax.swing.*;
import javax.swing.table.*;
public class TableHeaderIconTest {
//private final URL url = getClass().getResource("a.png");
public JComponent makeUI() {
String[] columnNames = {"Column1", "Column2", "Column3"};
JTable table = new JTable(new DefaultTableModel(columnNames, 3));
TableColumnModel m = table.getColumnModel();
for (int i = 0; i < m.getColumnCount(); i++) {
TableColumn column = m.getColumn(i);
column.setHeaderRenderer(new FilterIconHeaderRenderer4());
//column.setHeaderValue(
// String.format("<html><table><td><img src='%s'/><td>%s", url, columnNames[i]));
}
table.setAutoCreateRowSorter(true);
JPanel p = new JPanel(new BorderLayout());
p.add(new JScrollPane(table));
return p;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
try {
for (UIManager.LookAndFeelInfo laf : UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(laf.getName())) {
UIManager.setLookAndFeel(laf.getClassName());
}
}
} catch (Exception e) {
e.printStackTrace();
}
JFrame f = new JFrame();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.getContentPane().add(new TableHeaderIconTest().makeUI());
f.setSize(320, 240);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}
class FilterIconHeaderRenderer4 implements TableCellRenderer {
private final URL url = getClass().getResource("Ok2mc.png");
@Override public Component getTableCellRendererComponent(
JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
TableCellRenderer r = table.getTableHeader().getDefaultRenderer();
String str = Objects.toString(value, "");
String html = String.format("<html><table><td><img src='%s'/><td>%s", url, str);
return r.getTableCellRendererComponent(table, html, isSelected, hasFocus, row, column);
}
}
关于java - 在 JTable 列标题的左侧显示附加图标 (Nimbus)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/34155149/