org.eclipse.swt.dnd.ImageTransfer Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of org.eclipse.swt.gtk.linux.ppc64 Show documentation
SWT is an open source widget toolkit for Java designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.
The newest version!
/*******************************************************************************
 * Copyright (c) 2000, 2012 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.dnd;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.gtk.*;
import org.eclipse.swt.widgets.*;

/**
 * The class ImageTransfer provides a platform specific mechanism 
 * for converting an Image represented as a java ImageData to a 
 * platform specific representation of the data and vice versa.  
 * 
 * An example of a java ImageData is shown below:
 * 
 *  *     Image image = new Image(display, "C:\temp\img1.gif");
 *	   ImageData imgData = image.getImageData();
 * 
 *
 * @see Transfer
 * 
 * @since 3.4
 */
public class ImageTransfer extends ByteArrayTransfer {
	
	private static ImageTransfer _instance = new ImageTransfer();
	
	private static final String JPEG = "image/jpeg"; //$NON-NLS-1$
	private static final int JPEG_ID = registerType(JPEG);
	private static final String PNG = "image/png"; //$NON-NLS-1$
	private static final int PNG_ID = registerType(PNG);
	private static final String BMP = "image/bmp"; //$NON-NLS-1$
	private static final int BMP_ID = registerType(BMP);
	private static final String EPS = "image/eps"; //$NON-NLS-1$
	private static final int EPS_ID = registerType(EPS);
	private static final String PCX = "image/pcx"; //$NON-NLS-1$
	private static final int PCX_ID = registerType(PCX);
	private static final String PPM = "image/ppm"; //$NON-NLS-1$
	private static final int PPM_ID = registerType(PPM);
	private static final String RGB = "image/ppm"; //$NON-NLS-1$
	private static final int RGB_ID = registerType(RGB);
	private static final String TGA = "image/tga"; //$NON-NLS-1$
	private static final int TGA_ID = registerType(TGA);
	private static final String XBM = "image/xbm"; //$NON-NLS-1$
	private static final int XBM_ID = registerType(XBM);
	private static final String XPM = "image/xpm"; //$NON-NLS-1$
	private static final int XPM_ID = registerType(XPM);
	private static final String XV = "image/xv"; //$NON-NLS-1$
	private static final int XV_ID = registerType(XV);	
	
private ImageTransfer() {}

/**
 * Returns the singleton instance of the ImageTransfer class.
 *
 * @return the singleton instance of the ImageTransfer class
 */
public static ImageTransfer getInstance () {
	return _instance;
}

/**
 * This implementation of javaToNative converts an ImageData object represented
 * by java ImageData to a platform specific representation.
 * 
 * @param object a java ImageData containing the ImageData to be converted
 * @param transferData an empty TransferData object that will
 *  	be filled in on return with the platform specific format of the data
 * 
 * @see Transfer#nativeToJava
 */
public void javaToNative(Object object, TransferData transferData) {
	if (!checkImage(object) || !isSupportedType(transferData)) {
		DND.error(DND.ERROR_INVALID_DATA);
	}
	ImageData imgData = (ImageData)object;
	if (imgData == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	Image image = new Image(Display.getCurrent(), imgData);	
 	long /*int*/ pixbuf = ImageList.createPixbuf(image);
	if (pixbuf != 0) {
		String typeStr = "";
		if (transferData.type ==  JPEG_ID) typeStr = "jpeg";
		else if (transferData.type ==  PNG_ID) typeStr = "png";
		else if (transferData.type ==  BMP_ID) typeStr = "bmp";
		else if (transferData.type ==  EPS_ID) typeStr = "eps";
		else if (transferData.type ==  PCX_ID) typeStr = "pcx";
		else if (transferData.type ==  PPM_ID) typeStr = "ppm";
		else if (transferData.type ==  RGB_ID) typeStr = "rgb";
		else if (transferData.type ==  TGA_ID) typeStr = "tga";
		else if (transferData.type ==  XBM_ID) typeStr = "xbm";
		else if (transferData.type ==  XPM_ID) typeStr = "xpm";
		else if (transferData.type ==  XV_ID) typeStr = "xv";
		byte[] type = Converter.wcsToMbcs(null, typeStr , true);
		long /*int*/ [] buffer = new long /*int*/ [1];
		long /*int*/ [] len = new long /*int*/ [1];
		if (type == null) return;
		OS.gdk_pixbuf_save_to_bufferv(pixbuf, buffer, len, type, null, null, null);
		OS.g_object_unref(pixbuf);
		transferData.pValue = buffer[0];
		transferData.length = (int)(len[0] + 3) / 4 * 4;
		transferData.result = 1;
		transferData.format = 32;
	}
	image.dispose();
}

/**
 * This implementation of nativeToJava converts a platform specific 
 * representation of an image to java ImageData.  
 * 
 * @param transferData the platform specific representation of the data to be converted
 * @return a java ImageData of the image if the conversion was successful;
 * 		otherwise null
 * 
 * @see Transfer#javaToNative
 */
public Object nativeToJava(TransferData transferData) {
	ImageData imgData = null;
	if (transferData.length > 0) {
		long /*int*/ loader = OS.gdk_pixbuf_loader_new();
		try {
			OS.gdk_pixbuf_loader_write(loader, transferData.pValue, transferData.length, null);
			OS.gdk_pixbuf_loader_close(loader, null);
			long /*int*/ pixbuf = OS.gdk_pixbuf_loader_get_pixbuf(loader);
			if (pixbuf != 0) {
				Image img = Image.gtk_new_from_pixbuf(Display.getCurrent(), SWT.BITMAP, pixbuf);
				imgData = img.getImageData();
				img.dispose();
			}		
		} finally {
			OS.g_object_unref(loader);
		}
	}
	return imgData;
}

protected int[] getTypeIds(){
	return new int[]{PNG_ID, BMP_ID, EPS_ID, JPEG_ID, PCX_ID, PPM_ID, RGB_ID, TGA_ID, XBM_ID, XPM_ID, XV_ID};	
}

protected String[] getTypeNames(){
	return new String[]{PNG, BMP, EPS, JPEG, PCX, PPM, RGB, TGA, XBM, XPM, XV};
}

boolean checkImage(Object object) {
	if (object == null || !(object instanceof ImageData)) return false;
	return true;
}

protected boolean validate(Object object) {
	return checkImage(object);
}
}