有关JTree加载项目的时间问题,请高手指点。 list[i].isDirectory()你不是都知道了吗? 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 我这里有一个现成的例子给你参考吧,这个的功能只是把所有的目录都显示了,并没有显示文件,真的是和资源管理器比较象,不过你要看一下放几张图片到文件目录下,因为节点使用了图标,代码如下,有点长,分两页了import java.awt.*;import java.awt.event.*;import java.io.*;import java.util.*;import javax.swing.*;import javax.swing.tree.*;import javax.swing.event.*;public class FileTree1 extends JFrame { public static final ImageIcon ICON_COMPUTER = new ImageIcon("computer.gif"); public static final ImageIcon ICON_DISK = new ImageIcon("disk.gif"); public static final ImageIcon ICON_FOLDER = new ImageIcon("folder.gif"); public static final ImageIcon ICON_EXPANDEDFOLDER = new ImageIcon("expandedfolder.gif"); protected JTree m_tree; protected DefaultTreeModel m_model; protected JTextField m_display; public FileTree1() { super("Directories Tree"); setSize(400, 300); DefaultMutableTreeNode top = new DefaultMutableTreeNode( new IconData(ICON_COMPUTER, null, "Computer")); DefaultMutableTreeNode node; File[] roots = File.listRoots(); for (int k=0; k<roots.length; k++) { node = new DefaultMutableTreeNode(new IconData(ICON_DISK, null, new FileNode(roots[k]))); top.add(node); node.add( new DefaultMutableTreeNode(new Boolean(true))); } m_model = new DefaultTreeModel(top); m_tree = new JTree(m_model); m_tree.putClientProperty("JTree.lineStyle", "Angled"); TreeCellRenderer renderer = new IconCellRenderer(); m_tree.setCellRenderer(renderer); m_tree.addTreeExpansionListener(new DirExpansionListener()); m_tree.addTreeSelectionListener(new DirSelectionListener()); m_tree.getSelectionModel().setSelectionMode( TreeSelectionModel.SINGLE_TREE_SELECTION); m_tree.setShowsRootHandles(true); m_tree.setEditable(false); JScrollPane s = new JScrollPane(); s.getViewport().add(m_tree); getContentPane().add(s, BorderLayout.CENTER); m_display = new JTextField(); m_display.setEditable(false); getContentPane().add(m_display, BorderLayout.NORTH); WindowListener wndCloser = new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }; addWindowListener(wndCloser); setVisible(true); } DefaultMutableTreeNode getTreeNode(TreePath path) { return (DefaultMutableTreeNode)(path.getLastPathComponent()); } FileNode getFileNode(DefaultMutableTreeNode node) { if (node == null) return null; Object obj = node.getUserObject(); if (obj instanceof IconData) obj = ((IconData)obj).getObject(); if (obj instanceof FileNode) return (FileNode)obj; else return null; } // Make sure expansion is threaded and updating the tree model // only occurs within the event dispatching thread. class DirExpansionListener implements TreeExpansionListener { public void treeExpanded(TreeExpansionEvent event) { final DefaultMutableTreeNode node = getTreeNode( event.getPath()); final FileNode fnode = getFileNode(node); Thread runner = new Thread() { public void run() { if (fnode != null && fnode.expand(node)) { Runnable runnable = new Runnable() { public void run() { m_model.reload(node); } }; SwingUtilities.invokeLater(runnable); } } }; runner.start(); } public void treeCollapsed(TreeExpansionEvent event) {} } class DirSelectionListener implements TreeSelectionListener { public void valueChanged(TreeSelectionEvent event) { DefaultMutableTreeNode node = getTreeNode( event.getPath()); FileNode fnode = getFileNode(node); if (fnode != null) m_display.setText(fnode.getFile(). getAbsolutePath()); else m_display.setText(""); } } public static void main(String argv[]) { new FileTree1(); }}class IconCellRenderer extends JLabel implements TreeCellRenderer{ protected Color m_textSelectionColor; protected Color m_textNonSelectionColor; protected Color m_bkSelectionColor; protected Color m_bkNonSelectionColor; protected Color m_borderSelectionColor; protected boolean m_selected; public IconCellRenderer() { super(); m_textSelectionColor = UIManager.getColor( "Tree.selectionForeground"); m_textNonSelectionColor = UIManager.getColor( "Tree.textForeground"); m_bkSelectionColor = UIManager.getColor( "Tree.selectionBackground"); m_bkNonSelectionColor = UIManager.getColor( "Tree.textBackground"); m_borderSelectionColor = UIManager.getColor( "Tree.selectionBorderColor"); setOpaque(false); } public Component getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus) { DefaultMutableTreeNode node = (DefaultMutableTreeNode)value; Object obj = node.getUserObject(); setText(obj.toString()); if (obj instanceof Boolean) setText("Retrieving data..."); if (obj instanceof IconData) { IconData idata = (IconData)obj; if (expanded) setIcon(idata.getExpandedIcon()); else setIcon(idata.getIcon()); } else setIcon(null); setFont(tree.getFont()); setForeground(sel ? m_textSelectionColor : m_textNonSelectionColor); setBackground(sel ? m_bkSelectionColor : m_bkNonSelectionColor); m_selected = sel; return this; } public void paintComponent(Graphics g) { Color bColor = getBackground(); Icon icon = getIcon(); g.setColor(bColor); int offset = 0; if(icon != null && getText() != null) offset = (icon.getIconWidth() + getIconTextGap()); g.fillRect(offset, 0, getWidth() - 1 - offset, getHeight() - 1); if (m_selected) { g.setColor(m_borderSelectionColor); g.drawRect(offset, 0, getWidth()-1-offset, getHeight()-1); } super.paintComponent(g); }}class IconData{ protected Icon m_icon; protected Icon m_expandedIcon; protected Object m_data; public IconData(Icon icon, Object data) { m_icon = icon; m_expandedIcon = null; m_data = data; } public IconData(Icon icon, Icon expandedIcon, Object data) { m_icon = icon; m_expandedIcon = expandedIcon; m_data = data; } public Icon getIcon() { return m_icon; } public Icon getExpandedIcon() { return m_expandedIcon!=null ? m_expandedIcon : m_icon; } public Object getObject() { return m_data; } public String toString() { return m_data.toString(); }}class FileNode{ protected File m_file; public FileNode(File file) { m_file = file; } public File getFile() { return m_file; } public String toString() { return m_file.getName().length() > 0 ? m_file.getName() : m_file.getPath(); } public boolean expand(DefaultMutableTreeNode parent) { DefaultMutableTreeNode flag = (DefaultMutableTreeNode)parent.getFirstChild(); if (flag==null) // No flag return false; Object obj = flag.getUserObject(); if (!(obj instanceof Boolean)) return false; // Already expanded parent.removeAllChildren(); // Remove Flag File[] files = listFiles(); if (files == null) return true; Vector v = new Vector(); for (int k=0; k<files.length; k++) { File f = files[k]; if (!(f.isDirectory())) continue; FileNode newNode = new FileNode(f); boolean isAdded = false; for (int i=0; i<v.size(); i++) { FileNode nd = (FileNode)v.elementAt(i); if (newNode.compareTo(nd) < 0) { v.insertElementAt(newNode, i); isAdded = true; break; } } if (!isAdded) v.addElement(newNode); } for (int i=0; i<v.size(); i++) { FileNode nd = (FileNode)v.elementAt(i); IconData idata = new IconData(FileTree1.ICON_FOLDER, FileTree1.ICON_EXPANDEDFOLDER, nd); DefaultMutableTreeNode node = new DefaultMutableTreeNode(idata); parent.add(node); if (nd.hasSubDirs()) node.add(new DefaultMutableTreeNode( new Boolean(true) )); } return true; } public boolean hasSubDirs() { File[] files = listFiles(); if (files == null) return false; for (int k=0; k<files.length; k++) { if (files[k].isDirectory()) return true; } return false; } public int compareTo(FileNode toCompare) { return m_file.getName().compareToIgnoreCase( toCompare.m_file.getName() ); } protected File[] listFiles() { if (!m_file.isDirectory()) return null; try { return m_file.listFiles(); } catch (Exception ex) { JOptionPane.showMessageDialog(null, "Error reading directory "+m_file.getAbsolutePath(), "Warning", JOptionPane.WARNING_MESSAGE); return null; } }}好了,两部分组成一个文件,就能编译运行了 自己也写过,我的那个就是资源管理器的,不过很土,呵呵这个是书上的一个例子,我没有QQ,我的email是:[email protected]有空交流阿 队列的tostring方法 javax.naming.NoInitialContextException: Need to specify class name in environmen clone()对象克隆的问题 c++中调用java中嵌套对象的类的问题 insert into values 疑问 简单问题,但是很糊涂 求JSP版阿信做的“动态树” 菜鸟问题之 学java 要怎么建环境,我下载安装了jdk却不行?在线等待! 关于calendar的用法,有代码 awt中的鼠标事件如何区分左右键单击??? 不会安装JDK jubilder9的设置问题
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.event.*;public class FileTree1
extends JFrame
{
public static final ImageIcon ICON_COMPUTER =
new ImageIcon("computer.gif");
public static final ImageIcon ICON_DISK =
new ImageIcon("disk.gif");
public static final ImageIcon ICON_FOLDER =
new ImageIcon("folder.gif");
public static final ImageIcon ICON_EXPANDEDFOLDER =
new ImageIcon("expandedfolder.gif"); protected JTree m_tree;
protected DefaultTreeModel m_model;
protected JTextField m_display; public FileTree1()
{
super("Directories Tree");
setSize(400, 300); DefaultMutableTreeNode top = new DefaultMutableTreeNode(
new IconData(ICON_COMPUTER, null, "Computer")); DefaultMutableTreeNode node;
File[] roots = File.listRoots();
for (int k=0; k<roots.length; k++)
{
node = new DefaultMutableTreeNode(new IconData(ICON_DISK,
null, new FileNode(roots[k])));
top.add(node);
node.add( new DefaultMutableTreeNode(new Boolean(true)));
} m_model = new DefaultTreeModel(top);
m_tree = new JTree(m_model); m_tree.putClientProperty("JTree.lineStyle", "Angled"); TreeCellRenderer renderer = new
IconCellRenderer();
m_tree.setCellRenderer(renderer); m_tree.addTreeExpansionListener(new
DirExpansionListener()); m_tree.addTreeSelectionListener(new
DirSelectionListener()); m_tree.getSelectionModel().setSelectionMode(
TreeSelectionModel.SINGLE_TREE_SELECTION);
m_tree.setShowsRootHandles(true);
m_tree.setEditable(false); JScrollPane s = new JScrollPane();
s.getViewport().add(m_tree);
getContentPane().add(s, BorderLayout.CENTER); m_display = new JTextField();
m_display.setEditable(false);
getContentPane().add(m_display, BorderLayout.NORTH); WindowListener wndCloser = new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
};
addWindowListener(wndCloser);
setVisible(true);
} DefaultMutableTreeNode getTreeNode(TreePath path)
{
return (DefaultMutableTreeNode)(path.getLastPathComponent());
} FileNode getFileNode(DefaultMutableTreeNode node)
{
if (node == null)
return null;
Object obj = node.getUserObject();
if (obj instanceof IconData)
obj = ((IconData)obj).getObject();
if (obj instanceof FileNode)
return (FileNode)obj;
else
return null;
} // Make sure expansion is threaded and updating the tree model
// only occurs within the event dispatching thread.
class DirExpansionListener implements TreeExpansionListener
{
public void treeExpanded(TreeExpansionEvent event)
{
final DefaultMutableTreeNode node = getTreeNode(
event.getPath());
final FileNode fnode = getFileNode(node); Thread runner = new Thread()
{
public void run()
{
if (fnode != null && fnode.expand(node))
{
Runnable runnable = new Runnable()
{
public void run()
{
m_model.reload(node);
}
};
SwingUtilities.invokeLater(runnable);
}
}
};
runner.start();
} public void treeCollapsed(TreeExpansionEvent event) {}
}
class DirSelectionListener
implements TreeSelectionListener
{
public void valueChanged(TreeSelectionEvent event)
{
DefaultMutableTreeNode node = getTreeNode(
event.getPath());
FileNode fnode = getFileNode(node);
if (fnode != null)
m_display.setText(fnode.getFile().
getAbsolutePath());
else
m_display.setText("");
}
} public static void main(String argv[])
{
new FileTree1();
}
}class IconCellRenderer
extends JLabel
implements TreeCellRenderer
{
protected Color m_textSelectionColor;
protected Color m_textNonSelectionColor;
protected Color m_bkSelectionColor;
protected Color m_bkNonSelectionColor;
protected Color m_borderSelectionColor; protected boolean m_selected; public IconCellRenderer()
{
super();
m_textSelectionColor = UIManager.getColor(
"Tree.selectionForeground");
m_textNonSelectionColor = UIManager.getColor(
"Tree.textForeground");
m_bkSelectionColor = UIManager.getColor(
"Tree.selectionBackground");
m_bkNonSelectionColor = UIManager.getColor(
"Tree.textBackground");
m_borderSelectionColor = UIManager.getColor(
"Tree.selectionBorderColor");
setOpaque(false);
}
Object value, boolean sel, boolean expanded, boolean leaf,
int row, boolean hasFocus)
{
DefaultMutableTreeNode node =
(DefaultMutableTreeNode)value;
Object obj = node.getUserObject();
setText(obj.toString()); if (obj instanceof Boolean)
setText("Retrieving data..."); if (obj instanceof IconData)
{
IconData idata = (IconData)obj;
if (expanded)
setIcon(idata.getExpandedIcon());
else
setIcon(idata.getIcon());
}
else
setIcon(null); setFont(tree.getFont());
setForeground(sel ? m_textSelectionColor :
m_textNonSelectionColor);
setBackground(sel ? m_bkSelectionColor :
m_bkNonSelectionColor);
m_selected = sel;
return this;
}
public void paintComponent(Graphics g)
{
Color bColor = getBackground();
Icon icon = getIcon(); g.setColor(bColor);
int offset = 0;
if(icon != null && getText() != null)
offset = (icon.getIconWidth() + getIconTextGap());
g.fillRect(offset, 0, getWidth() - 1 - offset,
getHeight() - 1);
if (m_selected)
{
g.setColor(m_borderSelectionColor);
g.drawRect(offset, 0, getWidth()-1-offset, getHeight()-1);
}
super.paintComponent(g);
}
}class IconData
{
protected Icon m_icon;
protected Icon m_expandedIcon;
protected Object m_data; public IconData(Icon icon, Object data)
{
m_icon = icon;
m_expandedIcon = null;
m_data = data;
} public IconData(Icon icon, Icon expandedIcon, Object data)
{
m_icon = icon;
m_expandedIcon = expandedIcon;
m_data = data;
} public Icon getIcon()
{
return m_icon;
} public Icon getExpandedIcon()
{
return m_expandedIcon!=null ? m_expandedIcon : m_icon;
} public Object getObject()
{
return m_data;
} public String toString()
{
return m_data.toString();
}
}class FileNode
{
protected File m_file; public FileNode(File file)
{
m_file = file;
} public File getFile()
{
return m_file;
} public String toString()
{
return m_file.getName().length() > 0 ? m_file.getName() :
m_file.getPath();
} public boolean expand(DefaultMutableTreeNode parent)
{
DefaultMutableTreeNode flag =
(DefaultMutableTreeNode)parent.getFirstChild();
if (flag==null) // No flag
return false;
Object obj = flag.getUserObject();
if (!(obj instanceof Boolean))
return false; // Already expanded parent.removeAllChildren(); // Remove Flag File[] files = listFiles();
if (files == null)
return true; Vector v = new Vector(); for (int k=0; k<files.length; k++)
{
File f = files[k];
if (!(f.isDirectory()))
continue; FileNode newNode = new FileNode(f);
boolean isAdded = false;
for (int i=0; i<v.size(); i++)
{
FileNode nd = (FileNode)v.elementAt(i);
if (newNode.compareTo(nd) < 0)
{
v.insertElementAt(newNode, i);
isAdded = true;
break;
}
}
if (!isAdded)
v.addElement(newNode);
} for (int i=0; i<v.size(); i++)
{
FileNode nd = (FileNode)v.elementAt(i);
IconData idata = new IconData(FileTree1.ICON_FOLDER,
FileTree1.ICON_EXPANDEDFOLDER, nd);
DefaultMutableTreeNode node = new
DefaultMutableTreeNode(idata);
parent.add(node);
if (nd.hasSubDirs())
node.add(new DefaultMutableTreeNode(
new Boolean(true) ));
} return true;
} public boolean hasSubDirs()
{
File[] files = listFiles();
if (files == null)
return false;
for (int k=0; k<files.length; k++)
{
if (files[k].isDirectory())
return true;
}
return false;
}
public int compareTo(FileNode toCompare)
{
return m_file.getName().compareToIgnoreCase(
toCompare.m_file.getName() );
} protected File[] listFiles()
{
if (!m_file.isDirectory())
return null;
try
{
return m_file.listFiles();
}
catch (Exception ex)
{
JOptionPane.showMessageDialog(null,
"Error reading directory "+m_file.getAbsolutePath(),
"Warning", JOptionPane.WARNING_MESSAGE);
return null;
}
}
}好了,两部分组成一个文件,就能编译运行了
这个是书上的一个例子,我没有QQ,我的email是:[email protected]
有空交流阿