[ScaleBitmap] scale bitmap #bitmap #scale

ScaledBitmap.java

	//缩放图片大小
    public Bitmap scaleBitmap(Bitmap bitmap, int newWidth, int newHeight) {
        Bitmap b = bitmap;
        int width = b.getWidth();
        int height = b.getHeight();
        // 计算缩放比例
        float scaleWidth = ((float) newWidth) / width;
        float scaleHeight = ((float) newHeight) / height;
        // 取得想要缩放的matrix参数
        Matrix matrix = new Matrix();
        matrix.postScale(scaleWidth, scaleHeight);
        // 得到新的图片
        return Bitmap.createBitmap(b, 0, 0, width, height, matrix, true);
    }