【发布时间】：2012-12-15 07:48:25
【问题描述】：
- 我知道如何在 JTree 中设置自定义叶子图标
- 我知道如何为所有组节点设置自定义关闭/打开图标
但是我不能根据组节点名称设置自定义打开/关闭图标，例如节点可以称为电子邮件（所以有一个信封图标很好）或者一组可以称为任务等等。
我试图通过覆盖 DefaultTreeCellRenderer 类的 getTreeCellRendererComponent 方法来做到这一点
但是将icon 更改为当前的node 只会影响下一个节点！
如何为各个组设置自定义打开/关闭图标？
请看我的代码：
Employee.java
package com.ehsunbehravesh.swing;
import java.util.Random;
public class Employee {
public String name;
public int id;
public boolean isBoss;
public Employee[] employees;
public Employee(String name, boolean isBoss) {
this.name = name;
this.isBoss = isBoss;
this.id = new Random(System.currentTimeMillis()).nextInt(Integer.MAX_VALUE);
}
@Override
public String toString() {
return this.name;
}
static String randomName() {
String chars = "abcdefghijklmnopqrstuvwxyz";
StringBuilder builder = new StringBuilder();
Random r = new Random(System.currentTimeMillis());
int length = r.nextInt(10) + 1;
for (int i = 0; i < length; i++) {
builder.append(chars.charAt(r.nextInt(chars.length())));
}
return builder.toString();
}
}
CustomTreeNode.java
package com.ehsunbehravesh.swing;
import javax.swing.ImageIcon;
import javax.swing.tree.DefaultMutableTreeNode;
public class CustomTreeNode extends DefaultMutableTreeNode {
/**
* The icon which is displayed on the JTree object. open, close, leaf icon.
*/
private ImageIcon icon;
public CustomTreeNode(ImageIcon icon) {
this.icon = icon;
}
public CustomTreeNode(ImageIcon icon, Object userObject) {
super(userObject);
this.icon = icon;
}
public CustomTreeNode(ImageIcon icon, Object userObject, boolean allowsChildren) {
super(userObject, allowsChildren);
this.icon = icon;
}
public ImageIcon getIcon() {
return icon;
}
public void setIcon(ImageIcon icon) {
this.icon = icon;
}
}
CustomeTreeCellRenderer.java
package com.ehsunbehravesh.swing;
import java.awt.Component;
import javax.swing.JTree;
import javax.swing.tree.DefaultTreeCellRenderer;
class CustomeTreeCellRenderer extends DefaultTreeCellRenderer {
public CustomeTreeCellRenderer() {
}
@Override
public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus) {
super.getTreeCellRendererComponent(tree, value, leaf, expanded, leaf, row, hasFocus);
if (!leaf) {
CustomTreeNode node = (CustomTreeNode) value;
System.out.println(((Employee) node.getUserObject()).name);
if (node.getIcon() != null) {
System.out.println(node.getIcon().toString());
setClosedIcon(node.getIcon());
setOpenIcon(node.getIcon());
} else {
setClosedIcon(getDefaultClosedIcon());
setClosedIcon(getDefaultOpenIcon());
setOpenIcon(getDefaultOpenIcon());
}
}
return this;
}
}
Test1.java
package com.ehsunbehravesh.swing;
import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTree;
import javax.swing.tree.DefaultTreeModel;
class TreeSample {
public static void main(String args[]) {
JFrame f = new JFrame("JTree Sample");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel pnlMain = new JPanel(new BorderLayout());
pnlMain.setBackground(Color.white);
createTree(pnlMain);
f.setContentPane(pnlMain);
f.setSize(300, 200);
f.setVisible(true);
}
private static void createTree(JPanel pnlMain) {
Employee bigBoss = new Employee(Employee.randomName(), true);
Employee[] level1 = new Employee[5];
bigBoss.employees = level1;
for (int i = 0; i < level1.length; i++) {
level1[i] = new Employee(Employee.randomName(), true);
}
for (int i = 0; i < level1.length; i++) {
Employee employee = level1[i];
if (employee.isBoss) {
int count = 5;
employee.employees = new Employee[count];
for (int j = 0; j < employee.employees.length; j++) {
employee.employees[j] = new Employee(Employee.randomName(), false);
}
}
}
CustomTreeNode root = new CustomTreeNode(new ImageIcon("images/Circle_3.gif"), bigBoss);
DefaultTreeModel model = new DefaultTreeModel(root);
for (Employee employee : bigBoss.employees) {
CustomTreeNode boss = new CustomTreeNode(new ImageIcon("images/Circle_2.gif"), employee);
root.add(boss);
if (employee.isBoss) {
for (Employee employee1 : employee.employees) {
CustomTreeNode emp = new CustomTreeNode(new ImageIcon("images/Circle_1.gif"), employee1);
boss.add(emp);
}
}
}
JTree tree = new JTree(model);
tree.setCellRenderer(new CustomeTreeCellRenderer());
pnlMain.add(tree, BorderLayout.CENTER);
}
}
【问题讨论】：
标签： java swing icons jtree treecellrenderer