Java Image.getHeight方法代码示例

import com.google.gwt.user.client.ui.Image; //导入方法依赖的package包/类
/**
 * Returns the original height when using IE.
 * 
 * @see com.google.gwt.user.client.ui.Image#getHeight()
 */
@Override
public int getHeight() {
    int superHeight = super.getHeight();
    logger.log(Level.INFO, "superHeight:" + superHeight);
    logger.log(Level.INFO, "isAttached():" + isAttached());
    if ( (superHeight <= 0) ) {
        // If this is being run under IE the default answer may be 0 when it
        // shouldn't be, so return the height from a hidden and attached
        // temp image
        Image temp = new Image(this.getUrl());
        temp.getElement().getStyle().setVisibility(Visibility.HIDDEN);
        RootPanel.get().add(temp);
        logger.log(Level.WARNING, "temp.isAttached():" + temp.isAttached());
        int tempHeight = temp.getHeight();
        logger.log(Level.WARNING, "tempHeight:" + tempHeight);
        temp.removeFromParent();
        return tempHeight;
    }
    return superHeight;
}
 

import com.google.gwt.user.client.ui.Image; //导入方法依赖的package包/类
private ImageData scaleImage(Image image, double scaleToRatio) {
    Canvas canvasTmp = Canvas.createIfSupported();
    Context2d context = canvasTmp.getContext2d();

    int imageHeight = image.getHeight();

    double ch = (imageHeight * scaleToRatio);
    int imageWidth = image.getWidth();
    
    double cw = (imageWidth * scaleToRatio);

    canvasTmp.setCoordinateSpaceHeight((int) ch);
    canvasTmp.setCoordinateSpaceWidth((int) cw);

    // TODO: make a temp imageElement?
    ImageElement imageElement = ImageElement.as(image.getElement());

    // s = source
    // d = destination
    double sx = 0;
    double sy = 0;
    int imageElementWidth = imageElement.getWidth();
    if (imageElementWidth <= 0) {
        imageElementWidth = imageWidth;
    }
    double sw = imageElementWidth;
    int imageElementHeight = imageElement.getHeight();
    if (imageElementHeight <= 0) {
        imageElementHeight = imageHeight;
    }
    double sh = imageElementHeight;

    double dx = 0;
    double dy = 0;
    double dw = imageElementWidth;
    double dh = imageElementHeight;

    // tell it to scale image
    context.scale(scaleToRatio, scaleToRatio);

    // draw image to canvas
    context.drawImage(imageElement, sx, sy, sw, sh, dx, dy, dw, dh);

    // get image data
    double w = dw * scaleToRatio;
    double h = dh * scaleToRatio;
    ImageData imageData = null;
    try {
        imageData = context.getImageData(0, 0, w, h);
    } catch (Exception e) {
        // no image data. we'll try againg...
        String b = e.getLocalizedMessage();
    }

    int ht = (int) h + 10;
    int wt = (int) w + 10;
    
    // Clear the div, clear the drawing canvas then reinsert.  Otherwise, ghosts of the previous image appear.
    canvasDiv.clear();
            
    imageCanvasContext.clearRect(0, 0, imageCanvas.getCoordinateSpaceWidth(), imageCanvas.getCoordinateSpaceHeight());
    
    canvasDiv.add(imageCanvas, 0, 0);
    canvasDiv.add(drawingCanvas, 0, 0);
    
    imageCanvas.setCoordinateSpaceHeight(ht);
    imageCanvas.setCoordinateSpaceWidth(wt);
    
    drawingCanvas.setCoordinateSpaceHeight(ht);
    drawingCanvas.setCoordinateSpaceWidth(wt);
    
    canvasDiv.setSize(wt + "px", ht + "px");

    return imageData;
}
 

import com.google.gwt.user.client.ui.Image; //导入方法依赖的package包/类
/**
 * set position of a widget as the widget is centered on the given position.
 * @param p_w
 * @param p_wgtPixPosition position in pixel
 */
public void setWidgetPixPosition(Image p_w, AnPair p_wgtPixPosition)
{
  super.setWidgetPosition( p_w, p_wgtPixPosition.getX() - p_w.getWidth() / 2, p_wgtPixPosition
      .getY()
      - p_w.getHeight() / 2 );
  // p_w.setVisible( true );
}