android中bitmap缩放和阴影效果

1.缩放

    /**
     * zoom bitmap to certain size
     *
     * @param bitmap
     * @param width
     * @param height
     * @return
     */
    public static Bitmap zoomBitmap(Bitmap bitmap, int width, int height) {
        if (bitmap == null) {
            return null;
        }

        int w = bitmap.getWidth();
        int h = bitmap.getHeight();
        Matrix matrix = new Matrix();
        float scaleWidth = ((float) width / w);
        float scaleHeight = ((float) height / h);
        matrix.postScale(scaleWidth, scaleHeight);
        Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);
        return newbmp;
    }

2. 阴影
/**

     * add shadow to bitmap
     *
     * @param originalBitmap
     * @return
     */
    private Bitmap drawImageDropShadow(Bitmap originalBitmap) {

        BlurMaskFilter blurFilter = new BlurMaskFilter(1,
                BlurMaskFilter.Blur.NORMAL);
        Paint shadowPaint = new Paint();
        shadowPaint.setAlpha(50);
        shadowPaint.setColor(activity.getResources()
                .getColor(R.color.solid_red));
        shadowPaint.setMaskFilter(blurFilter);

        int[] offsetXY = new int[2];
        Bitmap shadowBitmap = originalBitmap
                .extractAlpha(shadowPaint, offsetXY);

        Bitmap shadowImage32 = shadowBitmap.copy(Bitmap.Config.ARGB_8888, true);
        Canvas c = new Canvas(shadowImage32);
        c.drawBitmap(originalBitmap, offsetXY[0], offsetXY[1], null);

return shadowImage32;
}

摘自 fhy_2008的专栏

补充：移动开发 , Android ,