疯狂JAVA讲义---第十二章：Swing编程（七）JTree树

public class SimpleJTree
{
JFrame jf = new JFrame("简单树");

JTree tree;
//定义几个初始节点
DefaultMutableTreeNode root = new DefaultMutableTreeNode("中国");
DefaultMutableTreeNode guangdong = new DefaultMutableTreeNode("广东");
DefaultMutableTreeNode guangxi = new DefaultMutableTreeNode("广西");
DefaultMutableTreeNode foshan = new DefaultMutableTreeNode("佛山");
DefaultMutableTreeNode shantou = new DefaultMutableTreeNode("汕头");
DefaultMutableTreeNode guilin = new DefaultMutableTreeNode("桂林");
DefaultMutableTreeNode nanning = new DefaultMutableTreeNode("南宁");

public void init()
{
//通过add方法建立树节点之间的父子关系
guangdong.add(foshan);
guangdong.add(shantou);
guangxi.add(guilin);
guangxi.add(nanning);
root.add(guangdong);
root.add(guangxi);
//以根节点创建树
tree = new JTree(root);

//默认连线
//tree.putClientProperty("JTree.lineStyle" , "Angeled");
//没有连线
tree.putClientProperty("JTree.lineStyle" , "None");
//水平分隔线
//tree.putClientProperty("JTree.lineStyle" , "Horizontal");

//设置是否显示根节点的“展开/折叠”图标,默认是false
tree.setShowsRootHandles(true);
//设置节点是否可见,默认是true
tree.setRootVisible(true);

jf.add(new JScrollPane(tree));
jf.pack();
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setVisible(true);
}

public static void main(String[] args)
{
new SimpleJTree().init();
}
}

public class EditJTree
{
JFrame jf;

JTree tree;
//上面JTree对象对应的model
DefaultTreeModel model;

//定义几个初始节点
DefaultMutableTreeNode root = new DefaultMutableTreeNode("中国");
DefaultMutableTreeNode guangdong = new DefaultMutableTreeNode("广东");
DefaultMutableTreeNode guangxi = new DefaultMutableTreeNode("广西");
DefaultMutableTreeNode foshan = new DefaultMutableTreeNode("佛山");
DefaultMutableTreeNode shantou = new DefaultMutableTreeNode("汕头");
DefaultMutableTreeNode guilin = new DefaultMutableTreeNode("桂林");
DefaultMutableTreeNode nanning = new DefaultMutableTreeNode("南宁");

//定义需要被拖动的TreePath
TreePath movePath;

JButton addSiblingButton = new JButton("添加兄弟节点");
JButton addChildButton = new JButton("添加子节点");
JButton deleteButton = new JButton("删除节点");
JButton editButton = new JButton("编辑当前节点");

public void init()
{
guangdong.add(foshan);
guangdong.add(shantou);
guangxi.add(guilin);
guangxi.add(nanning);
root.add(guangdong);
root.add(guangxi);

jf = new JFrame("树");
tree = new JTree(root);
//获取JTree对应的TreeModel对象
model = (DefaultTreeModel)tree.getModel();
//设置JTree可编辑
tree.setEditable(true);
MouseListener ml = new MouseAdapter()
{
//按下鼠标时候获得被拖动的节点
public void mousePressed(MouseEvent e)
{
//如果需要唯一确定某个节点，必须通过TreePath来获取。
TreePath tp = tree.getPathForLocation(e.getX(), e.getY());
if (tp != null)
{
movePath = tp;
}
}
//鼠标松开时获得需要拖到哪个父节点
public void mouseReleased(MouseEvent e)
{
//根据鼠标松开时的TreePath来获取TreePath
TreePath tp = tree.getPathForLocation(e.getX(), e.getY());

if (tp != null && movePath != null)
{
//阻止向子节点拖动
if (movePath.isDescendant(tp) && movePath != tp)
{
JOptionPane.showMessageDialog(jf, "目标节点是被移动节点的子节点，无法移动！",
"非法操作", JOptionPane.ERROR_MESSAGE );
return;
}
//既不是向子节点移动，而且鼠标按下、松开的不是同一个节点
else if (movePath != tp)
{
System.out.println(tp.getLastPathComponent());
//add方法可以先将原节点从原父节点删除，再添加到新父节点中
((DefaultMutableTreeNode)tp.getLastPathComponent()).add(
(DefaultMutableTreeNode)movePath.getLastPathComponent());
movePath = null;
tree.updateUI();
}
}
}
};
tree.addMouseListener(ml);

JPanel panel = new JPanel();

addSiblingButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
//获取选中节点
DefaultMutableTreeNode selectedNode
= (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
//如果节点为空，直接返回
if (selectedNode == null) return;
//获取该选中节点的父节点
DefaultMutableTreeNode parent
= (DefaultMutableTreeNode)selectedNode.getParent();
//如果父节点为空，直接返回
if (parent == null) return;
//创建一个新节点
DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("新节点");
//获取选中节点的选中索引
int selectedIndex = parent.getIndex(selectedNode);
//在选中位置插入新节点
model.insertNodeInto(newNode, parent, selectedIndex + 1);
//--------下面代码实现显示新节点（自动展开父节点）-------
//获取从根节点到新节点的所有节点
TreeNode[] nodes = model.getPathToRoot(newNode);
//使用指定的节点数组来创建TreePath
TreePath path = new TreePath(nodes);
//显示指定TreePath
tree.scrollPathToVisible(path);
}
});
panel.add(addSiblingButton);

addChildButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
//获取选中节点
DefaultMutableTreeNode selectedNode
= (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
//如果节点为空，直接返回
if (selectedNode == null) return;
//创建一个新节点
DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("新节点");
//直接通过model来添加新节点，则无需通过调用JTree的updateUI方法
//model.insertNodeInto(newNode, selectedNode, selectedNode.getChildCount());
//直接通过节点添加新节点，则需要调用tree的updateUI方法
selectedNode.add(newNode);
//--------下面代码实现显示新节点（自动展开父节点）-------
TreeNode[] nodes = model.getPathToRoot(newNode);
TreePath path = new TreePath(nodes);
tree.scrollPathToVisible(path);
tree.updateUI();
}
});
panel.add(addChildButton);

deleteButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
DefaultMutableTreeNode selectedNode
= (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
if (selectedNode != null && selectedNode.getParent() != null)
{
//删除指定节点
model.removeNodeFromParent(selectedNode);
}
}
});
panel.add(deleteButton);

editButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
TreePath selectedPath = tree.getSelectionPath();
if (selectedPath != null)
{
//编辑选中节点
tree.startEditingAtPath(selectedPath);
}
}
});
panel.add(editButton);

jf.add(new JScrollPane(tree));
jf.add(panel , BorderLayout.SOUTH);
jf.pack();
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setVisible(true);
}

public static void main(String[] args)
{
new EditJTree().init();
}
}

public class ExtendsDefaultTreeCellRenderer
{
JFrame jf = new JFrame("根据节点类型定义图标");

JTree tree;
//定义几个初始节点
DefaultMutableTreeNode root = new DefaultMutableTreeNode(
new NodeData(DBObjectType.ROOT , "数据库导航"));
DefaultMutableTreeNode salaryDb = new DefaultMutableTreeNode(
new NodeData(DBObjectType.DATABASE , "公司工资数据库"));
DefaultMutableTreeNode customerDb = new DefaultMutableTreeNode(
new NodeData(DBObjectType.DATABASE , "公司客户数据库"));
//定义salaryDb的两个子节点
DefaultMutableTreeNode employee = new DefaultMutableTreeNode(
new NodeData(DBObjectType.TABLE , "员工表"));
DefaultMutableTreeNode attend = new DefaultMutableTreeNode(
new NodeData(DBObjectType.TABLE , "考勤表"));
//定义customerDb的一个子节点
DefaultMutableTreeNode contact = new DefaultMutableTreeNode(
new NodeData(DBObjectType.TABLE , "联系方式表"));

//定义employee的三个子节点
DefaultMutableTreeNode id = new DefaultMutableTreeNode(
new NodeData(DBObjectType.INDEX , "员工ID"));
DefaultMutableTreeNode name = new DefaultMutableTreeNode(
new NodeData(DBObjectType.COLUMN , "姓名"));
DefaultMutableTreeNode gender = new DefaultMutableTreeNode(
new NodeData(DBObjectType.COLUMN , "性别"));

public void init()throws Exception
{
//通过add方法建立树节点之间的父子关系
root.add(salaryDb);
root.add(customerDb);
salaryDb.add(employee);
salaryDb.add(attend);
customerDb.add(contact);
employee.add(id);
employee.add(name);
employee.add(gender);
//以根节点创建树
tree = new JTree(root);

//设置该JTree使用自定义的节点绘制器
tree.setCellRenderer(new MyRenderer());

//设置是否显示根节点的“展开/折叠”图标,默认是false
tree.setShowsRootHandles(true);
//设置节点是否可见,默认是true
tree.setRootVisible(true);

//设置使用Windows风格外观
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
//更新JTree的UI外观
SwingUtilities.updateComponentTreeUI(tree);

jf.add(new JScrollPane(tree));
jf.pack();
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setVisible(true);
}

public static void main(String[] args) throws Exception
{
new ExtendsDefaultTreeCellRenderer().init();
}
}
//定义一个NodeData类，用于封装节点数据
class NodeData
{
public int nodeType;
public String nodeData;
public NodeData(int nodeType , String nodeData)
{
this.nodeType = nodeType;
this.nodeData = nodeData;
}
public String toString()
{
return nodeData;
}
}
//定义一个接口，该接口里包含数据库对象类型的常量
interface DBObjectType
{
int ROOT = 0;
int DATABASE = 1;
int TABLE = 2;
int COLUMN = 3;
int INDEX = 4;
}
class MyRenderer extends DefaultTreeCellRenderer
{
//初始化5个图标
ImageIcon rootIcon = new ImageIcon("icon/root.gif");
ImageIcon databaseIcon = new ImageIcon("icon/database.gif");
ImageIcon tableIcon = new ImageIcon("icon/table.gif");
ImageIcon columnIcon = new ImageIcon("icon/column.gif");
ImageIcon indexIcon = new ImageIcon("icon/index.gif");

public Component getTreeCellRendererComponent(JTree tree, Object value,
boolean sel, boolean expanded,  boolean leaf, int row, boolean hasFocus)
{
//执行父类默认的节点绘制操作
super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus);

DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;
NodeData data = (NodeData)node.getUserObject();
//根据数据节点里的nodeType数据决定节点图标
ImageIcon icon = null;
switch(data.nodeType)
{
case DBObjectType.ROOT:
icon = rootIcon;
break;
case DBObjectType.DATABASE:
icon = databaseIcon;
break;
case DBObjectType.TABLE:
icon = tableIcon;
break;
case DBObjectType.COLUMN:
icon = columnIcon;
break;
case DBObjectType.INDEX:
icon = indexIcon;
break;
}
//改变图标
this.setIcon(icon);
return this;
}
}