12 Bitmap缩放

 1 public  Bitmap zoomImage(Bitmap bgimage, double newWidth,
 2                                    double newHeight) {
 3         // 获取这个图片的宽和高
 4         float width = bgimage.getWidth();
 5         float height = bgimage.getHeight();
 6         // 创建操作图片用的matrix对象
 7         Matrix matrix = new Matrix();
 8         // 计算宽高缩放率
 9         float scaleWidth = ((float) newWidth) / width;
10         float scaleHeight = ((float) newHeight) / height;
11         // 缩放图片动作
12         matrix.postScale(scaleWidth, scaleHeight);
13         Bitmap bitmap = Bitmap.createBitmap(bgimage, 0, 0, (int) width,
14             (int) height, matrix, true);
15         return bitmap;
16     }