我有以下代码用于开发JTabbedPane“tab组件”。我在自定义选项卡式窗格中使用setTabComponentAt（index，tabComponent）设置它。
package com.example.tabpane;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import javax.swing.JLabel;
import javax.swing.event.EventListenerList;
import com.example.SwingUtilities;
public class TabComponent extends JLabel {
private Point mousePointerAt;
private Dimension crossIconDim = new Dimension(15, 15);
private int crossIconDimLeftPadding = 5;
private EventListenerList eventListeners = new EventListenerList();
public TabComponent() {
initComponent();
}
public TabComponent(String title) {
super(title);
setOpaque(false);
initComponent();
}
//You don't have to override the getSize() versions. It basically calls getWidth() and getHeight()
//Also you should NOT override getWidth() and getHeight() because the layout managers set that properties
//If you do the borders right/bottom edges won't be painted correctly
@Override
public Dimension getPreferredSize() {
Dimension preferredSize = super.getPreferredSize();
int width = (int)preferredSize.getWidth();
int height = (int)preferredSize.getHeight();
width += crossIconDim.getWidth() + crossIconDimLeftPadding;
height = Math.max(height, (int) crossIconDim.getHeight());
Dimension newSize = new Dimension(width, height);
return newSize;
}
@Override
public Dimension getMinimumSize() {
Dimension preferredSize = super.getMinimumSize();
int width = (int)preferredSize.getWidth();
int height = (int)preferredSize.getHeight();
width += crossIconDim.getWidth() + crossIconDimLeftPadding;
height = Math.max(height, (int) crossIconDim.getHeight());
Dimension newSize = new Dimension(width, height);
return newSize;
}
@Override
public Dimension getMaximumSize() {
Dimension preferredSize = super.getMaximumSize();
int width = (int)preferredSize.getWidth();
int height = (int)preferredSize.getHeight();
width += crossIconDim.getWidth() + crossIconDimLeftPadding;
height = Math.max(height, (int) crossIconDim.getHeight());
Dimension newSize = new Dimension(width, height);
return newSize;
}
private void initComponent() {
addMouseMotionListener(new MouseMotionAdapter() {
@Override
public void mouseMoved(MouseEvent e) {
SwingUtilities.bubbleEvent(e);
TabComponent tab = (TabComponent) e.getComponent();
tab.mousePointerAt = e.getPoint();
tab.repaint();
}
});
addMouseListener(new MouseAdapter() {
@Override
public void mouseExited(MouseEvent e) {
SwingUtilities.bubbleEvent(e);
TabComponent tab = (TabComponent) e.getComponent();
tab.mousePointerAt = null;
tab.repaint();
}
@Override
public void mouseClicked(MouseEvent e) {
SwingUtilities.bubbleEvent(e);
TabComponent tab = (TabComponent) e.getComponent();
if (tab.mousePointerAt != null) {
int componentWidth = tab.getWidth();
Insets insets = tab.getInsets();
Point gfxXlatePoint = new Point(componentWidth - (int) crossIconDim.getWidth() - insets.right, insets.top);
Rectangle paintRectangle = new Rectangle(gfxXlatePoint, crossIconDim);
if (mousePointerAt != null) {
if (paintRectangle.contains(mousePointerAt)) {
tab.fireTabEvent(new TabEvent(tab, TabEvent.TAB_CLOSING));
}
}
}
}
});
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D gfx = (Graphics2D) g.create();
int componentWidth = getWidth();
int ovalRadius = (int) (crossIconDim.getWidth());
Insets insets = getInsets();
Point gfxXlatePoint = new Point(componentWidth - (int) crossIconDim.getWidth() - insets.right, insets.top);
Rectangle paintRectangle = new Rectangle(gfxXlatePoint, crossIconDim);
gfx.translate(gfxXlatePoint.x, gfxXlatePoint.y);
boolean mouseOverCloseCue = false;
if (mousePointerAt != null) {
if (paintRectangle.contains(mousePointerAt)) {
mouseOverCloseCue = true;
}
}
gfx.setStroke(new BasicStroke(2));
gfx.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
Insets crossIconPadding = new Insets(5, 5, 5, 5);
if (mouseOverCloseCue) {
gfx.setColor(new Color(0xf49f94));
//The mouse pointer is on the x mark
gfx.fillOval(0, 0, ovalRadius, ovalRadius);
gfx.setColor(Color.WHITE);
gfx.drawLine(0 + crossIconPadding.left, 0 + crossIconPadding.top, (int)crossIconDim.getWidth() - crossIconPadding.right, (int)crossIconDim.getHeight() - crossIconPadding.bottom);
gfx.drawLine((int)crossIconDim.getWidth() - crossIconPadding.right, 0 + crossIconPadding.top, 0 + crossIconPadding.left, (int)crossIconDim.getHeight() - crossIconPadding.bottom);
} else {
gfx.setColor(Color.BLACK);
gfx.drawLine(0 + crossIconPadding.left, 0 + crossIconPadding.top, (int)crossIconDim.getWidth() - crossIconPadding.right, (int)crossIconDim.getHeight() - crossIconPadding.bottom);
gfx.drawLine((int)crossIconDim.getWidth() - crossIconPadding.right, 0 + crossIconPadding.top, 0 + crossIconPadding.left, (int)crossIconDim.getHeight() - crossIconPadding.bottom);
}
gfx.dispose();
}
public void addTabEventListener(TabEventListener listener) {
eventListeners.add(TabEventListener.class, listener);
}
public void removeTabEventListener(TabEventListener listener) {
eventListeners.remove(TabEventListener.class, listener);
}
protected void fireTabEvent(TabEvent evt) {
Object[] listeners = eventListeners.getListeners(TabEventListener.class);
for (int i = 0, n = listeners.length; i < n; i++) {
((TabEventListener) listeners[i]).handleEvent(evt);
}
}
}
以下代码是我自定义的JTabbedPane
package com.example.tabpane;
import java.awt.Component;
import javax.swing.JTabbedPane;
public class ClosingTabbedPane extends JTabbedPane {
/**
*
*/
private static final long serialVersionUID = 1L;
public ClosingTabbedPane() {
}
@Override
public void addTab(String title, Component component) {
super.addTab(title, component);
final int index = getTabCount() - 1;
TabComponent tabLabel = new TabComponent(title);
tabLabel.addTabEventListener(new TabEventListener() {
@Override
public void handleEvent(TabEvent evt) {
if (evt.getEventType() == TabEvent.TAB_CLOSING) {
ClosingTabbedPane.this.removeTabAt(index);
}
}
});
setTabComponentAt(index, tabLabel);
}
}
问题是，标签组件不起作用，因为它消耗了鼠标事件。当用户单击选项卡组件时，TabbedPane不会更改选项卡。我可以处理点击我自己并更改选项卡可见但我在想是否是另一种方式来搞砸事件。我试着编写一个通用的事件冒泡器，但它正在吞噬StackOverflowError。
package com.example;
import java.awt.AWTEvent;
import java.awt.Component;
import java.awt.Container;
public class SwingUtilities {
public static void bubbleEvent(AWTEvent event) {
Component source = (Component) event.getSource();
Container parent = source.getParent();
int i = 0, deep = 10;
while (parent != null && i < deep) {
i++;
System.out.println("Dispatching to the parent with i = " + i);
parent.dispatchEvent(event);
parent = parent.getParent();
}
}
}
答案 0 :(得分：1)
你正在以错误的方式思考这个问题。
为什么不创建一个由CloseIcon包含的TabComponent类，而不是创建一个单独的，所有同时执行这两个操作的emracassing类。
通过这种方式，您可以将逻辑分离并隔离责任，而无需借助脏兮兮的工作来解决问题
（抱歉，我对你的代码进行了一些检查）
CloseIcon 这一切都是绘制关闭图标并响应鼠标事件。单击时，它会触发ActionEvent（作为一般事件），以便其他组件收听......
public class CloseIcon extends JPanel {
private static final Dimension CROSS_ICON_SIZE = new Dimension(15, 15);
private static final int CROSS_ICON_INSET = 5;
private boolean mouseInTheHouse = false;
public CloseIcon() {
setOpaque(false);
addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
fireActionPerformed();
}
@Override
public void mouseEntered(MouseEvent e) {
mouseInTheHouse = true;
}
@Override
public void mouseExited(MouseEvent e) {
mouseInTheHouse = false;
}
});
}
public void addActionListener(ActionListener listener) {
listenerList.add(ActionListener.class, listener);
}
protected void fireActionPerformed() {
ActionListener[] listeners = listenerList.getListeners(ActionListener.class);
if (listeners.length > 0) {
ActionEvent evt = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "Closed");
for (ActionListener listener : listeners) {
listener.actionPerformed(evt);
}
}
}
//You don't have to override the getSize() versions. It basically calls getWidth() and getHeight()
//Also you should NOT override getWidth() and getHeight() because the layout managers set that properties
//If you do the borders right/bottom edges won't be painted correctly
@Override
public Dimension getPreferredSize() {
return new Dimension(CROSS_ICON_SIZE.width + CROSS_ICON_INSET, CROSS_ICON_SIZE.height);
}
@Override
public Dimension getMinimumSize() {
return getPreferredSize();
}
@Override
public Dimension getMaximumSize() {
return getPreferredSize();
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D gfx = (Graphics2D) g.create();
int componentWidth = getWidth();
int ovalRadius = (int) (CROSS_ICON_SIZE.getWidth());
Insets insets = getInsets();
Point gfxXlatePoint = new Point(componentWidth - (int) CROSS_ICON_SIZE.getWidth() - insets.right, insets.top);
Rectangle paintRectangle = new Rectangle(gfxXlatePoint, CROSS_ICON_SIZE);
gfx.translate(gfxXlatePoint.x, gfxXlatePoint.y);
gfx.setStroke(new BasicStroke(2));
gfx.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
Insets crossIconPadding = new Insets(5, 5, 5, 5);
if (mouseInTheHouse) {
gfx.setColor(new Color(0xf49f94));
//The mouse pointer is on the x mark
gfx.fillOval(0, 0, ovalRadius, ovalRadius);
gfx.setColor(Color.WHITE);
gfx.drawLine(0 + crossIconPadding.left, 0 + crossIconPadding.top, (int) CROSS_ICON_SIZE.getWidth() - crossIconPadding.right, (int) CROSS_ICON_SIZE.getHeight() - crossIconPadding.bottom);
gfx.drawLine((int) CROSS_ICON_SIZE.getWidth() - crossIconPadding.right, 0 + crossIconPadding.top, 0 + crossIconPadding.left, (int) CROSS_ICON_SIZE.getHeight() - crossIconPadding.bottom);
} else {
gfx.setColor(Color.BLACK);
gfx.drawLine(0 + crossIconPadding.left, 0 + crossIconPadding.top, (int) CROSS_ICON_SIZE.getWidth() - crossIconPadding.right, (int) CROSS_ICON_SIZE.getHeight() - crossIconPadding.bottom);
gfx.drawLine((int) CROSS_ICON_SIZE.getWidth() - crossIconPadding.right, 0 + crossIconPadding.top, 0 + crossIconPadding.left, (int) CROSS_ICON_SIZE.getHeight() - crossIconPadding.bottom);
}
gfx.dispose();
}
}
TabComponent TabComponent只是JPanel，上面有JLabel和CloseIcon。该组件侦听CloseIcon的{{1}}，然后用它来触发ActionEvents
TabEventpublic class TabComponent extends JPanel {
private CloseIcon closeIcon;
public TabComponent(String title) {
setLayout(new GridBagLayout());
setOpaque(false);
JLabel lblTitle = new JLabel(title);
closeIcon = new CloseIcon();
closeIcon.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
fireTabEvent(new TabEvent(this));//, TabEvent.TAB_CLOSING));
}
});
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.anchor = GridBagConstraints.WEST;
add(lblTitle, gbc);
gbc.gridx++;
gbc.weightx = 0;
gbc.anchor = GridBagConstraints.NORTHEAST;
add(closeIcon);
}
public void addTabEventListener(TabEventListener listener) {
listenerList.add(TabEventListener.class, listener);
}
public void removeTabEventListener(TabEventListener listener) {
listenerList.remove(TabEventListener.class, listener);
}
protected void fireTabEvent(TabEvent evt) {
Object[] listeners = listenerList.getListeners(TabEventListener.class);
for (int i = 0, n = listeners.length; i < n; i++) {
((TabEventListener) listeners[i]).handleEvent(evt);
}
}
}