Android - 縦横比を守ってネットから画像を取得

Android - 縦横比を守ってネットから画像を取得

IMAGE_MAX_HEIGHT、IMAGE_MAX_WIDTHを適当に設定してあげれば、引数のURLの画像をBitmapにして返します。Android端末において、Bitmapがメモリ的にかなりくせものなので、finallyでgcしてます。本当にこれが最適なのかは謎^^

    public static Bitmap getBitmapFromURL(String strUrl) throws IOException {
        HttpURLConnection con = null;
        InputStream in = null;
        Bitmap bitmap = null;
        Matrix matrix = null;
        try {

            URL url = new URL(strUrl);
            con = (HttpURLConnection) url.openConnection();
            con.setUseCaches(true);
            con.setRequestMethod("GET");
            con.setReadTimeout(500000);
            con.setConnectTimeout(50000);
            con.connect();
            in = con.getInputStream();
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inPurgeable = true;
            options.inPreferredConfig = Bitmap.Config.RGB_565;
            bitmap = BitmapFactory.decodeStream(in, null, options);

            int h = bitmap.getHeight();
            int w = bitmap.getWidth();
            float resizeScaleHeight = IMAGE_MAX_HEIGHT / Float.valueOf(h);
            float resizeScaleWidth = IMAGE_MAX_WIDTH / Float.valueOf(w);
            if (resizeScaleHeight > resizeScaleWidth && w > IMAGE_MAX_WIDTH) {
                resizeScaleHeight = IMAGE_MAX_WIDTH / Float.valueOf(w);
                resizeScaleWidth = IMAGE_MAX_WIDTH / Float.valueOf(w);
            } else if (h > IMAGE_MAX_HEIGHT) {
                resizeScaleHeight = IMAGE_MAX_HEIGHT / Float.valueOf(h);
                resizeScaleWidth = IMAGE_MAX_HEIGHT / Float.valueOf(h);
            }

            matrix = new Matrix();
            matrix.postScale(resizeScaleWidth, resizeScaleHeight);
            return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
        } finally {
            try {
                if (con != null)
                    con.disconnect();
                if (in != null)
                    in.close();
            } catch (Exception e) {
            }
            bitmap = null;
            matrix = null;
            System.gc();
        }
    }