两个JTree之间的单向拖拽

王朝java/jsp·作者佚名 2006-01-09

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最近因为在一个项目中要实现JTree之间的拖拽，刚刚学习开始学习Java，参照网上的代码完成的，现在贴出来共享，希望对和我一样的菜鸟有点帮助，有什么错误的话还请多多指正。

DragSourceTree.java

package aabbcc;

import javax.swing.JTree;

import java.awt.dnd.DragGestureListener;

import java.awt.dnd.DragSourceListener;

import java.awt.dnd.DragSourceDragEvent;

import java.awt.dnd.DragSourceEvent;

import java.awt.dnd.DragSourceDropEvent;

import java.awt.dnd.DragGestureEvent;

import java.awt.dnd.DragSource;

import javax.swing.tree.DefaultMutableTreeNode;

import java.awt.datatransfer.StringSelection;

/**

* Title: JTree之间的拖拽中的DragSourceTree

* Description:通过向从“源树”中拖拽结点在目标树中重新构造一棵树，实现JTree之间的拖拽单向拖拽，这个类是“源树”。

* @author awaysrain(绝对零度)

* @version 1.0

public class DragSourceTree

extends JTree

implements DragGestureListener, DragSourceListener {

private DragSource dragSource = null;

/**

* Construct the source tree

public DragSourceTree() {

super();

dragSource = DragSource.getDefaultDragSource();

dragSource.createDefaultDragGestureRecognizer(this,

java.awt.dnd.DnDConstants.

ACTION_COPY_OR_MOVE, this);

}

/**

* Construct the source tree

* @param treeNode DefaultMutableTreeNode

public DragSourceTree(DefaultMutableTreeNode treeNode) {

super(treeNode);

dragSource = DragSource.getDefaultDragSource();

dragSource.createDefaultDragGestureRecognizer(this,

java.awt.dnd.DnDConstants.

ACTION_COPY_OR_MOVE, this);

}

/**

* dragGestureRecognized

* @param dge DragGestureEvent

public void dragGestureRecognized(DragGestureEvent dge) {

java.awt.Cursor cursor = null;

cursor = DragSource.DefaultCopyDrop; //set cursor

java.awt.Point jap = dge.getDragOrigin(); //drag point

int x = (int) jap.getX();

int y = (int) jap.getY();

javax.swing.tree.TreePath tp = this.getPathForLocation(x, y); //get drag node path

if (tp != null) {

DefaultMutableTreeNode node1 = (DefaultMutableTreeNode)

tp.getLastPathComponent(); //get drag node

serializableNode(node1); //Serializable node object

}

//event start

dge.startDrag(cursor, new StringSelection("drag"), this);

}

/**

* dragEnter

* @param dsde DragSourceDragEvent

public void dragEnter(DragSourceDragEvent dsde) {

}

/**

* dragOver

* @param dsde DragSourceDragEvent

public void dragOver(DragSourceDragEvent dsde) {

}

/**

* dropActionChanged

* @param dsde DragSourceDragEvent

public void dropActionChanged(DragSourceDragEvent dsde) {

}

/**

* dragDropEnd

* @param dsde DragSourceDropEvent

public void dragDropEnd(DragSourceDropEvent dsde) {

}

/**

* dragExit

* @param dse DragSourceEvent

public void dragExit(DragSourceEvent dse) {

}

/**

*Serializable node

* @param node DefaultMutableTreeNode

private void serializableNode(DefaultMutableTreeNode node) {

try {

java.io.FileOutputStream objfile = new java.io.FileOutputStream(

"DragNode.OBJ");

java.io.ObjectOutputStream p = new java.io.ObjectOutputStream(objfile);

p.writeObject(node);

p.flush();

objfile.close();

}

catch (java.io.IOException e) {

System.out.println(e.toString());

}

DragTargetTree.java

package aabbcc;

import javax.swing.JTree;

import java.awt.dnd.DropTargetListener;

import java.awt.dnd.DropTargetDragEvent;

import java.awt.dnd.DropTargetDropEvent;

import java.awt.dnd.DropTargetEvent;

import java.awt.dnd.DropTarget;

import java.io.*;

import javax.swing.tree.DefaultMutableTreeNode;

/**

* Title: JTree之间的拖拽中的DragTargetTree

* Description:通过向从“源树”中拖拽结点在目标树中重新构造一棵树，实现JTree之间的拖拽单向拖拽，这个类是“目的树”

* @author awaysrain(绝对零度)

* @version 1.0

public class DragTargetTree

extends JTree

implements DropTargetListener {

/**

* Construct the target tree

public DragTargetTree() {

super();

DropTarget dropTarget = new DropTarget(this,

java.awt.dnd.DnDConstants.

ACTION_COPY_OR_MOVE, this);

}

/**

* Construct the target tree

* @param treeNode DefaultMutableTreeNode

public DragTargetTree(DefaultMutableTreeNode treeNode) {

super(treeNode);

DropTarget dropTarget = new DropTarget(this,

java.awt.dnd.DnDConstants.

ACTION_COPY_OR_MOVE, this);

}

/**

* dragEnter

* @param dtde DropTargetDragEvent

public void dragEnter(DropTargetDragEvent dtde) {

}

/**

* dragOver

* @param dtde DropTargetDragEvent

public void dragOver(DropTargetDragEvent dtde) {

}

/**

* dropActionChanged

* @param dtde DropTargetDragEvent

public void dropActionChanged(DropTargetDragEvent dtde) {

}

/**

* drop

* @param dtde DropTargetDropEvent

public void drop(DropTargetDropEvent dtde) {

dtde.acceptDrop(java.awt.dnd.DnDConstants.ACTION_COPY); //accept drop

java.awt.Point ap = dtde.getLocation(); // get event point

int x = (int) ap.getX();

int y = (int) ap.getY();

javax.swing.tree.DefaultMutableTreeNode parnode;

javax.swing.tree.TreePath tp = this.getPathForLocation(x, y);

if (tp != null) {

try {

//get drop tree node with treepath

javax.swing.tree.DefaultMutableTreeNode no1 =

(javax.swing.tree.DefaultMutableTreeNode) tp.getLastPathComponent();

parnode = no1;

int index = parnode.getChildCount();

// get drop tree mode

javax.swing.tree.DefaultTreeModel tm =

(javax.swing.tree.DefaultTreeModel)this.getModel();

javax.swing.tree.DefaultMutableTreeNode node2 =

new javax.swing.tree.DefaultMutableTreeNode();

node2 = readNode();

tm.insertNodeInto(node2, parnode, index);

}

catch (java.lang.Exception e) {

System.out.println(e.toString());

}

/**

* dragExit

* @param dte DropTargetEvent

public void dragExit(DropTargetEvent dte) {

}

/**

* read the node

* @return DefaultMutableTreeNode

private DefaultMutableTreeNode readNode() {

FileInputStream objfile = null;

try {

objfile = new java.io.FileInputStream("DragNode.OBJ");

ObjectInputStream q = new ObjectInputStream(objfile);

DefaultMutableTreeNode node = (DefaultMutableTreeNode) q.readObject();

return node;

}

catch (Exception ex) {

return null;

}

Demo.java

package aabbcc;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import com.borland.jbcl.layout.*;

/**

* Title: JTree之间的拖拽测试

* Description:通过向从“源树”中拖拽结点在目标树中重新构造一棵树，实现JTree之间的拖拽单向拖拽，这个类测试的类

* @author awaysrain(绝对零度)

public class Demo extends JFrame {

JPanel contentPane;

JScrollPane jScrollPane1 = new JScrollPane();

XYLayout xYLayout1 = new XYLayout();

DragSourceTree jTree1 = new DragSourceTree();

JScrollPane jScrollPane2 = new JScrollPane();

DragTargetTree jTree2 = new DragTargetTree();

JLabel jLabel1 = new JLabel();

JLabel jLabel2 = new JLabel();

//Construct the frame

public Demo () {

enableEvents(AWTEvent.WINDOW_EVENT_MASK);

try {

jbInit();

}

catch(Exception e) {

e.printStackTrace();

}

//Component initialization

private void jbInit() throws Exception {

contentPane = (JPanel) this.getContentPane();

contentPane.setLayout(xYLayout1);

this.setSize(new Dimension(400, 300));

this.setTitle("Demo");

jLabel1.setFont(new java.awt.Font("DialogInput", 0, 16));

jLabel1.setText("源树");

jLabel2.setEnabled(true);

jLabel2.setFont(new java.awt.Font("DialogInput", 0, 16));

jLabel2.setDebugGraphicsOptions(0);

jLabel2.setDoubleBuffered(false);

jLabel2.setVerifyInputWhenFocusTarget(true);

jLabel2.setDisplayedMnemonic('0');

jLabel2.setText("目标树");

jLabel2.setVerticalAlignment(javax.swing.SwingConstants.CENTER);

jLabel2.setVerticalTextPosition(javax.swing.SwingConstants.CENTER);

contentPane.add(jLabel1, new XYConstraints(35, 8, 139, 27));

contentPane.add(jLabel2, new XYConstraints(214, 10, 149, 20));

contentPane.add(jScrollPane2, new XYConstraints(211, 31, 159, 231));

contentPane.add(jScrollPane1, new XYConstraints(25, 31, 153, 230));

jScrollPane1.getViewport().add(jTree1, null);

jScrollPane2.getViewport().add(jTree2, null);

}

//Overridden so we can exit when window is closed

protected void processWindowEvent(WindowEvent e) {

super.processWindowEvent(e);

if (e.getID() == WindowEvent.WINDOW_CLOSING) {

System.exit(0);

}