dndfnl.java

追加最小化按钮： 利用JNI

//
//  DnDFile.java
//      Dropped File Viewer Sample Code
//      http://www5.big.or.jp/~tera/Labo/Java2/j2dnd.html
//  Copyright(C) 2000 S.Terada, All rights reserved
//
import java.io.*;
import javax.swing.*;
import java.awt.dnd.*;
import java.awt.event.*;
import java.awt.datatransfer.*;

public class DnDFnL extends JFrame {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private static FileDropAcceptableLabel lab = null;

	//static final DataFlavor[] supportedFlavors = { null };
	//static {
	//	try {
	//		supportedFlavors[0] = new DataFlavor(
	//				DataFlavor.javaRemoteObjectMimeType);
	//	} catch (Exception ex) {
	//		ex.printStackTrace();
	//	}
	//}

	/**
	 * This method initializes this
	 */
	private void initialize() {
		this.setSize(383, 333);
		this.setLocation(320, 300);
        this.setTitle("Drag And Drop");
	}

	// Main
	public static void main(String args[]) {
		DnDFnL win = new DnDFnL();
		win.setVisible(true);
	}

	// Constructor
	public DnDFnL() {
		initialize();
		addWindowListener(new WindowAdapter() {
			public void windowClosing(WindowEvent e) {
				System.exit(0);
			}
		});
		lab = new FileDropAcceptableLabel();
		getContentPane().add(lab);
	}

	// Drop Acceptor (Internal Class)
	class FileDropAcceptableLabel extends JLabel implements DropTargetListener {

		/**
		 * 
		 */
		private static final long serialVersionUID = 1L;
		private DropTarget dropTarget = null;

		// Constructor
		public FileDropAcceptableLabel() {
			super();
			dropTarget = new DropTarget(this, DnDConstants.ACTION_COPY_OR_MOVE,	this, true);
			dropTarget.getClass();
		}

		// Drag Enter Event Handler
		public void dragEnter(DropTargetDragEvent e){
			e.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
		}

		// Drop Event Handler
		public void drop(DropTargetDropEvent e) {
			e.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);

			// get string data from drop
			try {
				Object source = e.getTransferable().getTransferData(DataFlavor.stringFlavor);
				//System.out.println("source is: \n" + source);
				JOptionPane.showMessageDialog(this, source);
			} catch (Exception ex){
				System.out.println(ex.getMessage());
			}

			// get file and name from drop
			try {
				if ((e.getDropAction() & DnDConstants.ACTION_COPY_OR_MOVE) != 0) {
					Transferable trans = e.getTransferable();

					java.util.List lis = (java.util.List) trans.getTransferData(DataFlavor.javaFileListFlavor);
					File file = (File) lis.get(0);
					String sFileName = file.getAbsolutePath();
					//System.out.println("Dropped File:" + sFileName);
					JOptionPane.showMessageDialog(this, sFileName);
					if ( sFileName.indexOf(".jpg") > 0 || sFileName.indexOf(".JPG") > 0 ||
						 sFileName.indexOf(".gif") > 0 || sFileName.indexOf(".GIF") > 0 ){
						setIcon(new ImageIcon(sFileName));
						//pack();
					}
					e.dropComplete(true);
				} else {
					e.dropComplete(false);
				}
			} catch (Exception ex) {
				System.out.println(ex.getMessage());
				e.dropComplete(false);
			}
		}

		// The other events should be ignored
		public void dragExit(DropTargetEvent e) {}
		public void dragOver(DropTargetDragEvent e) {}
		public void dropActionChanged(DropTargetDragEvent e) {}
	}
}