FileTransferDropTargetListener.java

/*******************************************************************************
 * Copyright (c) 2007 Exadel, Inc. and Red Hat, Inc.
 * Distributed under license by Red Hat, Inc. All rights reserved.
 * This program is made available under the terms of the
 * Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Exadel, Inc. and Red Hat, Inc. - initial API and implementation
 ******************************************************************************/ 
package org.jboss.tools.seam.ui.pages.editor.dnd;

import java.io.File;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.jface.util.TransferDropTargetListener;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.DropTargetEvent;
import org.eclipse.swt.dnd.FileTransfer;
import org.eclipse.swt.dnd.Transfer;

import org.jboss.tools.common.model.util.EclipseResourceUtil;
import org.jboss.tools.seam.ui.pages.editor.PagesEditor;
import org.jboss.tools.seam.ui.pages.editor.edit.PagesDiagramEditPart;

public class FileTransferDropTargetListener implements TransferDropTargetListener {
	PagesEditor editor;
	boolean baseDropAccept = false;

	public FileTransferDropTargetListener(PagesEditor editor) {
		this.editor = editor;
	}

	public void dragOperationChanged(DropTargetEvent event) {

	}

	public void dragEnter(DropTargetEvent event) {
		String[] os = (String[]) FileTransfer.getInstance().nativeToJava(
				event.currentDataType);
		if (os == null || os.length != 1 || !new File(os[0]).isFile())
			return;
		IFile f = ResourcesPlugin.getWorkspace().getRoot().getFileForLocation(
				new Path(os[0]));
		if (f == null || !f.exists())
			return;
		if (!DndHelper.drag(EclipseResourceUtil.getObjectByResource(f)))
			return;

		if (DndHelper.isDropEnabled(editor.getPagesModel().getData())) {
			baseDropAccept = true;
		} else {
			baseDropAccept = false;
		}
	}

	public void dragOver(DropTargetEvent event) {
		if (!baseDropAccept)
			event.detail = DND.DROP_NONE;
		else
			event.detail = DND.DROP_COPY;

	}

	public void dragLeave(DropTargetEvent event) {
	}

	public void dropAccept(DropTargetEvent event) {
	}

	public void drop(DropTargetEvent event) {
		org.eclipse.swt.graphics.Point parentPoint = editor
				.getScrollingGraphicalViewer().getControl().toControl(event.x,
						event.y);
		Point point = new Point(parentPoint.x, parentPoint.y);
		((PagesDiagramEditPart) editor.getScrollingGraphicalViewer()
				.getRootEditPart().getChildren().get(0)).getFigure()
				.translateToRelative(point);
		DndHelper.drop(editor.getPagesModel().getData(), point);
	}

	public Transfer getTransfer() {
		return FileTransfer.getInstance();
	}

	public boolean isEnabled(DropTargetEvent event) {
		return true;
	}

}