Problems with Eclipse Window Builder Composite - eclipse

Question

I am experiencing some problems with Window Builder example:
https://developers.google.com/web-toolkit/tools/gwtdesigner/features/custom_composites
When I copy the codes to my Eclipse, I have an error in the code:
customComposite.setFirstFieldBackground(SWTResourceManager
.getColor(SWT.COLOR_YELLOW));
Eclipse tells me that there's no SWTResourceManager.
When I try to exhibit the form in design mode, another error occours in the code:
final Label thirdFieldLabel = new Label(customComposite.getComposite(),
SWT.NONE);
thirdFieldLabel.setText("Third Field");
Error:
org.eclipse.wb.internal.core.utils.exception.DesignerException: 2005 (Null as parent argument.).
Considering that this example is very common in Web, even in the Help Files of the own WindowBuilder, I supose that I hanven't the correct settings/files to my application.
What would I do differently? Thanks!

Answer 1

What is happening is that SWTResourceManager is a class that is created in the plugin when you use the design view to set things like color, it is specific to your plugin. So when you copy code into another plugin that references that class you will get a class not found exception. Easiest thing to do,is copy the code. Delete the set color, set the color in the editor in your new plugin and a SWTResourceManager wil be auto created for that plugin. The second NPE not sure sounds environment specific but as a rule of thumb swt resource manager is bundle specific.

Answer 2

The SWTResourceManager class is usually generated in a com.swtdesigner package when you create a new WindowBuilder project using Eclipse wizard (File > New > Other > WindowBuilder> SWTDesigner).
Try to generate your project using this wizard.
If you still don't have this class generated here is its code :
package com.swtdesigner;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Cursor;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Display;
/**
* Utility class for managing OS resources associated with SWT controls such as colors, fonts, images, etc.
* <p>
* !!! IMPORTANT !!! Application code must explicitly invoke the <code>dispose()</code> method to release the
* operating system resources managed by cached objects when those objects and OS resources are no longer
* needed (e.g. on application shutdown)
* <p>
* This class may be freely distributed as part of any application or plugin.
* <p>
* #author scheglov_ke
* #author Dan Rubel
*/
public class SWTResourceManager {
////////////////////////////////////////////////////////////////////////////
//
// Color
//
////////////////////////////////////////////////////////////////////////////
private static Map<RGB, Color> m_colorMap = new HashMap<RGB, Color>();
/**
* Returns the system {#link Color} matching the specific ID.
*
* #param systemColorID
* the ID value for the color
* #return the system {#link Color} matching the specific ID
*/
public static Color getColor(int systemColorID) {
Display display = Display.getCurrent();
return display.getSystemColor(systemColorID);
}
/**
* Returns a {#link Color} given its red, green and blue component values.
*
* #param r
* the red component of the color
* #param g
* the green component of the color
* #param b
* the blue component of the color
* #return the {#link Color} matching the given red, green and blue component values
*/
public static Color getColor(int r, int g, int b) {
return getColor(new RGB(r, g, b));
}
/**
* Returns a {#link Color} given its RGB value.
*
* #param rgb
* the {#link RGB} value of the color
* #return the {#link Color} matching the RGB value
*/
public static Color getColor(RGB rgb) {
Color color = m_colorMap.get(rgb);
if (color == null) {
Display display = Display.getCurrent();
color = new Color(display, rgb);
m_colorMap.put(rgb, color);
}
return color;
}
/**
* Dispose of all the cached {#link Color}'s.
*/
public static void disposeColors() {
for (Color color : m_colorMap.values()) {
color.dispose();
}
m_colorMap.clear();
}
////////////////////////////////////////////////////////////////////////////
//
// Image
//
////////////////////////////////////////////////////////////////////////////
/**
* Maps image paths to images.
*/
private static Map<String, Image> m_imageMap = new HashMap<String, Image>();
/**
* Returns an {#link Image} encoded by the specified {#link InputStream}.
*
* #param stream
* the {#link InputStream} encoding the image data
* #return the {#link Image} encoded by the specified input stream
*/
protected static Image getImage(InputStream stream) throws IOException {
try {
Display display = Display.getCurrent();
ImageData data = new ImageData(stream);
if (data.transparentPixel > 0) {
return new Image(display, data, data.getTransparencyMask());
}
return new Image(display, data);
} finally {
stream.close();
}
}
/**
* Returns an {#link Image} stored in the file at the specified path.
*
* #param path
* the path to the image file
* #return the {#link Image} stored in the file at the specified path
*/
public static Image getImage(String path) {
Image image = m_imageMap.get(path);
if (image == null) {
try {
image = getImage(new FileInputStream(path));
m_imageMap.put(path, image);
} catch (Exception e) {
image = getMissingImage();
m_imageMap.put(path, image);
}
}
return image;
}
/**
* Returns an {#link Image} stored in the file at the specified path relative to the specified class.
*
* #param clazz
* the {#link Class} relative to which to find the image
* #param path
* the path to the image file, if starts with <code>'/'</code>
* #return the {#link Image} stored in the file at the specified path
*/
public static Image getImage(Class<?> clazz, String path) {
String key = clazz.getName() + '|' + path;
Image image = m_imageMap.get(key);
if (image == null) {
try {
image = getImage(clazz.getResourceAsStream(path));
m_imageMap.put(key, image);
} catch (Exception e) {
image = getMissingImage();
m_imageMap.put(key, image);
}
}
return image;
}
private static final int MISSING_IMAGE_SIZE = 10;
/**
* #return the small {#link Image} that can be used as placeholder for missing image.
*/
private static Image getMissingImage() {
Image image = new Image(Display.getCurrent(), MISSING_IMAGE_SIZE, MISSING_IMAGE_SIZE);
//
GC gc = new GC(image);
gc.setBackground(getColor(SWT.COLOR_RED));
gc.fillRectangle(0, 0, MISSING_IMAGE_SIZE, MISSING_IMAGE_SIZE);
gc.dispose();
//
return image;
}
/**
* Style constant for placing decorator image in top left corner of base image.
*/
public static final int TOP_LEFT = 1;
/**
* Style constant for placing decorator image in top right corner of base image.
*/
public static final int TOP_RIGHT = 2;
/**
* Style constant for placing decorator image in bottom left corner of base image.
*/
public static final int BOTTOM_LEFT = 3;
/**
* Style constant for placing decorator image in bottom right corner of base image.
*/
public static final int BOTTOM_RIGHT = 4;
/**
* Internal value.
*/
protected static final int LAST_CORNER_KEY = 5;
/**
* Maps images to decorated images.
*/
#SuppressWarnings("unchecked")
private static Map<Image, Map<Image, Image>>[] m_decoratedImageMap = new Map[LAST_CORNER_KEY];
/**
* Returns an {#link Image} composed of a base image decorated by another image.
*
* #param baseImage
* the base {#link Image} that should be decorated
* #param decorator
* the {#link Image} to decorate the base image
* #return {#link Image} The resulting decorated image
*/
public static Image decorateImage(Image baseImage, Image decorator) {
return decorateImage(baseImage, decorator, BOTTOM_RIGHT);
}
/**
* Returns an {#link Image} composed of a base image decorated by another image.
*
* #param baseImage
* the base {#link Image} that should be decorated
* #param decorator
* the {#link Image} to decorate the base image
* #param corner
* the corner to place decorator image
* #return the resulting decorated {#link Image}
*/
public static Image decorateImage(final Image baseImage, final Image decorator, final int corner) {
if (corner <= 0 || corner >= LAST_CORNER_KEY) {
throw new IllegalArgumentException("Wrong decorate corner");
}
Map<Image, Map<Image, Image>> cornerDecoratedImageMap = m_decoratedImageMap[corner];
if (cornerDecoratedImageMap == null) {
cornerDecoratedImageMap = new HashMap<Image, Map<Image, Image>>();
m_decoratedImageMap[corner] = cornerDecoratedImageMap;
}
Map<Image, Image> decoratedMap = cornerDecoratedImageMap.get(baseImage);
if (decoratedMap == null) {
decoratedMap = new HashMap<Image, Image>();
cornerDecoratedImageMap.put(baseImage, decoratedMap);
}
//
Image result = decoratedMap.get(decorator);
if (result == null) {
Rectangle bib = baseImage.getBounds();
Rectangle dib = decorator.getBounds();
//
result = new Image(Display.getCurrent(), bib.width, bib.height);
//
GC gc = new GC(result);
gc.drawImage(baseImage, 0, 0);
if (corner == TOP_LEFT) {
gc.drawImage(decorator, 0, 0);
} else if (corner == TOP_RIGHT) {
gc.drawImage(decorator, bib.width - dib.width, 0);
} else if (corner == BOTTOM_LEFT) {
gc.drawImage(decorator, 0, bib.height - dib.height);
} else if (corner == BOTTOM_RIGHT) {
gc.drawImage(decorator, bib.width - dib.width, bib.height - dib.height);
}
gc.dispose();
//
decoratedMap.put(decorator, result);
}
return result;
}
/**
* Dispose all of the cached {#link Image}'s.
*/
public static void disposeImages() {
// dispose loaded images
{
for (Image image : m_imageMap.values()) {
image.dispose();
}
m_imageMap.clear();
}
// dispose decorated images
for (int i = 0; i < m_decoratedImageMap.length; i++) {
Map<Image, Map<Image, Image>> cornerDecoratedImageMap = m_decoratedImageMap[i];
if (cornerDecoratedImageMap != null) {
for (Map<Image, Image> decoratedMap : cornerDecoratedImageMap.values()) {
for (Image image : decoratedMap.values()) {
image.dispose();
}
decoratedMap.clear();
}
cornerDecoratedImageMap.clear();
}
}
}
////////////////////////////////////////////////////////////////////////////
//
// Font
//
////////////////////////////////////////////////////////////////////////////
/**
* Maps font names to fonts.
*/
private static Map<String, Font> m_fontMap = new HashMap<String, Font>();
/**
* Maps fonts to their bold versions.
*/
private static Map<Font, Font> m_fontToBoldFontMap = new HashMap<Font, Font>();
/**
* Returns a {#link Font} based on its name, height and style.
*
* #param name
* the name of the font
* #param height
* the height of the font
* #param style
* the style of the font
* #return {#link Font} The font matching the name, height and style
*/
public static Font getFont(String name, int height, int style) {
return getFont(name, height, style, false, false);
}
/**
* Returns a {#link Font} based on its name, height and style. Windows-specific strikeout and underline
* flags are also supported.
*
* #param name
* the name of the font
* #param size
* the size of the font
* #param style
* the style of the font
* #param strikeout
* the strikeout flag (warning: Windows only)
* #param underline
* the underline flag (warning: Windows only)
* #return {#link Font} The font matching the name, height, style, strikeout and underline
*/
public static Font getFont(String name, int size, int style, boolean strikeout, boolean underline) {
String fontName = name + '|' + size + '|' + style + '|' + strikeout + '|' + underline;
Font font = m_fontMap.get(fontName);
if (font == null) {
FontData fontData = new FontData(name, size, style);
if (strikeout || underline) {
try {
Class<?> logFontClass = Class.forName("org.eclipse.swt.internal.win32.LOGFONT"); //$NON-NLS-1$
Object logFont = FontData.class.getField("data").get(fontData); //$NON-NLS-1$
if (logFont != null && logFontClass != null) {
if (strikeout) {
logFontClass.getField("lfStrikeOut").set(logFont, Byte.valueOf((byte) 1)); //$NON-NLS-1$
}
if (underline) {
logFontClass.getField("lfUnderline").set(logFont, Byte.valueOf((byte) 1)); //$NON-NLS-1$
}
}
} catch (Throwable e) {
System.err
.println("Unable to set underline or strikeout" + " (probably on a non-Windows platform). " + e); //$NON-NLS-1$ //$NON-NLS-2$
}
}
font = new Font(Display.getCurrent(), fontData);
m_fontMap.put(fontName, font);
}
return font;
}
/**
* Returns a bold version of the given {#link Font}.
*
* #param baseFont
* the {#link Font} for which a bold version is desired
* #return the bold version of the given {#link Font}
*/
public static Font getBoldFont(Font baseFont) {
Font font = m_fontToBoldFontMap.get(baseFont);
if (font == null) {
FontData fontDatas[] = baseFont.getFontData();
FontData data = fontDatas[0];
font = new Font(Display.getCurrent(), data.getName(), data.getHeight(), SWT.BOLD);
m_fontToBoldFontMap.put(baseFont, font);
}
return font;
}
/**
* Dispose all of the cached {#link Font}'s.
*/
public static void disposeFonts() {
// clear fonts
for (Font font : m_fontMap.values()) {
font.dispose();
}
m_fontMap.clear();
// clear bold fonts
for (Font font : m_fontToBoldFontMap.values()) {
font.dispose();
}
m_fontToBoldFontMap.clear();
}
////////////////////////////////////////////////////////////////////////////
//
// Cursor
//
////////////////////////////////////////////////////////////////////////////
/**
* Maps IDs to cursors.
*/
private static Map<Integer, Cursor> m_idToCursorMap = new HashMap<Integer, Cursor>();
/**
* Returns the system cursor matching the specific ID.
*
* #param id
* int The ID value for the cursor
* #return Cursor The system cursor matching the specific ID
*/
public static Cursor getCursor(int id) {
Integer key = Integer.valueOf(id);
Cursor cursor = m_idToCursorMap.get(key);
if (cursor == null) {
cursor = new Cursor(Display.getDefault(), id);
m_idToCursorMap.put(key, cursor);
}
return cursor;
}
/**
* Dispose all of the cached cursors.
*/
public static void disposeCursors() {
for (Cursor cursor : m_idToCursorMap.values()) {
cursor.dispose();
}
m_idToCursorMap.clear();
}
////////////////////////////////////////////////////////////////////////////
//
// General
//
////////////////////////////////////////////////////////////////////////////
/**
* Dispose of cached objects and their underlying OS resources. This should only be called when the cached
* objects are no longer needed (e.g. on application shutdown).
*/
public static void dispose() {
disposeColors();
disposeImages();
disposeFonts();
disposeCursors();
}
}