Java UIImage.getCGImage方法代码示例

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
/**
 * 
 * @param image
 * @return a copy of the given image, adding an alpha channel if it doesn't
 *         already have one
 */
public static UIImage addAlpha(UIImage image) {
    if (hasAlpha(image)) {
        return image;
    }

    CGImage i = image.getCGImage();
    long width = i.getWidth();
    long height = i.getHeight();

    // The bitsPerComponent and bitmapInfo values are hard-coded to prevent
    // an "unsupported parameter combination" error
    CGBitmapContext offscreenContext = CGBitmapContext.create(width, height, 8, 0, i.getColorSpace(),
            new CGBitmapInfo(CGBitmapInfo.ByteOrderDefault.value() | CGImageAlphaInfo.PremultipliedFirst.value())); // TODO
                                                                                                                    // could
                                                                                                                    // be
                                                                                                                    // improved

    // Draw the image into the context and retrieve the new image, which
    // will now have an alpha layer
    offscreenContext.drawImage(new CGRect(0, 0, width, height), i);
    CGImage ia = offscreenContext.toImage();
    UIImage alphaImage = new UIImage(ia);

    return alphaImage;
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
/**
 * 
 * @param image
 * @param newSize
 * @param transform
 * @param transpose
 * @param quality
 * @return a copy of the image that has been transformed using the given
 *         affine transform and scaled to the new size The new image's
 *         orientation will be UIImageOrientationUp, regardless of the
 *         current image's orientation If the new size is not integral, it
 *         will be rounded up
 */
private static UIImage resize(UIImage image, CGSize newSize, CGAffineTransform transform, boolean transpose,
        CGInterpolationQuality quality) {
    CGRect newRect = new CGRect(0, 0, newSize.getWidth(), newSize.getHeight()).integral();
    CGRect transposedRect = new CGRect(0, 0, newRect.getSize().getHeight(), newRect.getSize().getWidth());
    CGImage i = image.getCGImage();

    // Build a context that's the same dimensions as the new size
    CGBitmapContext bitmap = CGBitmapContext.create((long) newRect.getSize().getWidth(), (long) newRect.getSize()
            .getHeight(), i.getBitsPerComponent(), 0, i.getColorSpace(), i.getBitmapInfo());

    // Rotate and/or flip the image if required by its orientation
    bitmap.concatCTM(transform);

    // Set the quality level to use when rescaling
    bitmap.setInterpolationQuality(quality);

    // Draw into the context; this scales the image
    bitmap.drawImage(transpose ? transposedRect : newRect, i);

    // Get the resized image from the context and a UIImage
    CGImage ni = bitmap.toImage();
    UIImage newImage = new UIImage(ni);

    return newImage;
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
/**
 * 
 * @param image
 * @param borderSize
 * @return a copy of the image with a transparent border of the given size
 *         added around its edges. If the image has no alpha layer, one will
 *         be added to it.
 */
public static UIImage addTransparentBorder(UIImage image, int borderSize) {
    // If the image does not have an alpha layer, add one
    image = addAlpha(image);

    CGRect newRect = new CGRect(0, 0, image.getSize().getWidth() + borderSize * 2, image.getSize().getHeight()
            + borderSize * 2);

    CGImage i = image.getCGImage();
    // Build a context that's the same dimensions as the new size
    CGBitmapContext bitmap = CGBitmapContext.create((long) newRect.getSize().getWidth(), (long) newRect.getSize()
            .getHeight(), i.getBitsPerComponent(), 0, i.getColorSpace(), i.getBitmapInfo());

    // Draw the image in the center of the context, leaving a gap around the
    // edges
    CGRect imageLocation = new CGRect(borderSize, borderSize, image.getSize().getWidth(), image.getSize()
            .getHeight());
    bitmap.drawImage(imageLocation, i);
    CGImage borderImage = bitmap.toImage();

    // Create a mask to make the border transparent, and combine it with the
    // image
    CGImage maskImage = newBorderMask(borderSize, newRect.getSize());
    CGImage tbi = CGImage.createWithMask(borderImage, maskImage);
    UIImage transparentBorderImage = new UIImage(tbi);

    return transparentBorderImage;
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
/**
 * Creates a copy of this image with rounded corners If borderSize is
 * non-zero, a transparent border of the given size will also be added
 * Original author: Björn Sållarp. Used with permission. See:
 * http://blog.sallarp.com/iphone-uiimage-round-corners/
 * 
 * @param image
 * @param cornerSize
 * @param borderSize
 * @return
 */
private static UIImage createRoundedCornerImage(UIImage image, int cornerSize, int borderSize) {
    // If the image does not have an alpha layer, add one
    image = addAlpha(image);

    // Build a context that's the same dimensions as the new size
    CGImage i = image.getCGImage();
    CGBitmapContext context = CGBitmapContext.create((long) image.getSize().getWidth(), (long) image.getSize()
            .getHeight(), i.getBitsPerComponent(), 0, i.getColorSpace(), i.getBitmapInfo());

    // Create a clipping path with rounded corners
    context.beginPath();
    addRoundedRectToPath(new CGRect(borderSize, borderSize, image.getSize().getWidth() - borderSize * 2, image
            .getSize().getHeight() - borderSize * 2)
            , context, cornerSize, cornerSize);
    context.closePath();
    context.clip();

    // Draw the image to the context; the clipping path will make anything
    // outside the rounded rect transparent
    context.drawImage(new CGRect(0, 0, image.getSize().getWidth(), image.getSize().getHeight()), i);

    // Create a CGImage from the context
    CGImage clippedImage = context.toImage();

    // Create a UIImage from the CGImage
    UIImage roundedImage = new UIImage(clippedImage);
    return roundedImage;
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
private ImageImpl.Data toData (Scale scale, UIImage image) {
  CGImage bitmap = image.getCGImage();
  return new ImageImpl.Data(scale, bitmap, (int)bitmap.getWidth(), (int)bitmap.getHeight());
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
@Override public Image transform(BitmapTransformer xform) {
  UIImage ximage = new UIImage(((RoboBitmapTransformer) xform).transform(cgImage()));
  return new RoboImage(gfx, scale, ximage.getCGImage(), source);
}
 

import org.robovm.apple.uikit.UIImage; //导入方法依赖的package包/类
private static CGImage getCGImage (String name) {
    int ix = name.lastIndexOf('/');
    if (ix != -1) name = name.substring(ix);
    UIImage uiImage = UIImage.getImage(name);
    return uiImage.getCGImage();
}