com.google.gwt.dom.client.ImageElement Java Examples

/**
 * Redisplays the sample image where the zones can be visually defined
 */
private void updateSample() {
	if (selectedOcrTemplate != null && selectedOcrTemplate.getSample() != null) {
		String url = Util.contextPath() + "ocrtemplateimage/" + selectedOcrTemplate.getId() + "?random="
				+ new Date().getTime();
		sample = new ImageWithCanvases(url, getWidth().intValue() - 50, null, new CallBack() {

			@Override
			public void onImagesLoaded(ImageElement[] imageElements) {
				showZones();
			}
		});

		editorPanel.addMember(sample);
	}
}
 

private CanvasElement prepareMissingTileImage() {
	int tileSize = DjvuContext.getTileSize();
	CanvasElement canvas = createImage(tileSize, tileSize);
	Context2d context2d = canvas.getContext2d();
	context2d.setFillStyle("white");
	context2d.fillRect(0, 0, canvas.getWidth(), canvas.getHeight());
	Image image = new Image();
	final ImageElement imageElement = image.getElement().cast();
	imageElement.getStyle().setProperty("visibility", "hidden");
	Event.setEventListener(imageElement, event -> {
		if (Event.ONLOAD == event.getTypeInt()) {
			missingTileImage.getContext2d().drawImage(imageElement, 0, 0);
			RootPanel.get().getElement().removeChild(imageElement);
		}
	});
	RootPanel.get().getElement().appendChild(imageElement);
	image.setUrl(getBlankImageUrl());
	return canvas;
}
 

private void showPage(int page) {
	if (pageImage != null) {
		captureNotesPosition();
		bottom.removeMembers(bottom.getMembers());
	}

	pageImage = new ImageWithCanvases(getPageUrl(page), null, new CallBack() {

		@Override
		public void onImagesLoaded(ImageElement[] imageElements) {
			// Reload the document to update the pages count
			if (document.getPages() <= 1)
				DocumentService.Instance.get().getById(document.getId(), new AsyncCallback<GUIDocument>() {

					@Override
					public void onFailure(Throwable caught) {
						Log.serverError(caught);
					}

					@Override
					public void onSuccess(GUIDocument dc) {
						document.setPages(dc.getPages());
						pageCursor.setMax(document.getPages());
						pageCursor.setHint("/" + (document.getPages() > 0 ? document.getPages() : 1));
					}
				});
			showAnnotations(page);
		}
	});
	bottom.addMember(pageImage);
}
 

/**
 * Creates texture region from byte[].
 * <p>
 * GWT platform requires additional step (as far as i know) to deal with Pixmap. It is need to load Image element
 * and wait until it is loaded.
 *
 * @param bytes    Image byte[] representation, not null
 * @param consumer Consumer where you should deal with region, not null
 */
public static void createTextureFromBytes(byte[] bytes, final Consumer<TextureRegion> consumer) {
    String base64 = "data:image/png;base64," + new String(Base64Coder.encode(bytes));
    final Image image = new Image();
    image.setVisible(false);
    image.addLoadHandler(new LoadHandler() {
        @Override
        public void onLoad(LoadEvent event) {
            ImageElement imageElement = image.getElement().cast();
            Pixmap pixmap = new Pixmap(imageElement);
            GdxFIRLogger.log("Image loaded");
            final int orgWidth = pixmap.getWidth();
            final int orgHeight = pixmap.getHeight();
            int width = MathUtils.nextPowerOfTwo(orgWidth);
            int height = MathUtils.nextPowerOfTwo(orgHeight);
            final Pixmap potPixmap = new Pixmap(width, height, pixmap.getFormat());
            potPixmap.drawPixmap(pixmap, 0, 0, 0, 0, pixmap.getWidth(), pixmap.getHeight());
            pixmap.dispose();
            TextureRegion region = new TextureRegion(new Texture(potPixmap), 0, 0, orgWidth, orgHeight);
            potPixmap.dispose();
            RootPanel.get().remove(image);
            consumer.accept(region);
        }
    });
    image.setUrl(base64);
    RootPanel.get().add(image);
}
 

private GPixmap decodeJPEG(CachedInputStream iff) throws IOException {
	final GPixmap result = new GPixmap();

	final Image image = new Image();
	final ImageElement imageElement = image.getElement().cast();
	imageElement.getStyle().setProperty("visibility", "hidden");
	Event.setEventListener(imageElement, new EventListener() {
		@Override
		public void onBrowserEvent(Event event) {
			if (Event.ONLOAD == event.getTypeInt()) {
				final int w = imageElement.getWidth(), h = imageElement.getHeight();
				final Canvas canvas = Canvas.createIfSupported();
				canvas.setWidth(w + "px");
				canvas.setCoordinateSpaceWidth(w);
				canvas.setHeight(h + "px");
				canvas.setCoordinateSpaceHeight(h);
				canvas.getContext2d().drawImage(imageElement, 0, 0);

				result.init(h, w, null);
				//TODO result.setImageData(canvas.getContext2d().getImageData(0, 0, w, h));
			}
		}
	});
	
	StringBuilder data = new StringBuilder();
	int b;
	while ((b = iff.read()) != -1) {
		data.append((char) b);
	}
	String dataURL = "data:image/jpeg;base64," + btoa(data.toString());
	image.setUrl(dataURL);

	return result;
}
 

protected Image(Image source) {
	super(source);
	this.imgElement = ImageElement.as(this.getElement());

	this.setSrc(source.src);
	this.setAlt(source.alt);
	this.widthPx = source.widthPx;
	this.heightPx = source.heightPx;
	this.keepPropertions = source.keepPropertions;

	this.resetSize();
}
 

public int getWidth() {
    return ((ImageElement)getElement().cast()).getWidth();
}
 

public int getHeight() {
    return ((ImageElement)getElement().cast()).getHeight();
}
 

private ImageElement getAvatar() {
  if (avatar == null) {
    avatar = load(id, Components.AVATAR).cast();
  }
  return avatar;
}
 

public Image() {
	super(ImageElement.TAG);
	this.imgElement = ImageElement.as(this.getElement());
}
 

public void drawImage(Image image, int x, int y) {
    ctx.drawImage(ImageElement.as(image.getElement()), x, y);
}
 

private ImageElement getAvatar() {
  if (avatar == null) {
    avatar = load(id, Components.AVATAR).cast();
  }
  return avatar;
}
 

/**
 * Draws a scaled subset of an image.
 *
 * @param image an {@link com.google.gwt.dom.client.CanvasElement} object
 * @param sx    the x coordinate of the upper-left corner of the source
 *              rectangle
 * @param sy    the y coordinate of the upper-left corner of the source
 *              rectangle
 * @param sw    the width of the source rectangle
 * @param sh    the width of the source rectangle
 * @param dx    the x coordinate of the upper-left corner of the destination
 *              rectangle
 * @param dy    the y coordinate of the upper-left corner of the destination
 *              rectangle
 * @param dw    the width of the destination rectangle
 * @param dh    the height of the destination rectangle
 */
public final void drawImage(Image image, double sx, double sy, double sw, double sh, double dx, double dy,
        double dw, double dh) {
    ctx.drawImage(ImageElement.as(image.getElement()), sx, sy, sw, sh, dx, dy, dw, dh);
}
 

public native ImageElement getImage();