Android--字符串和Drawable之間互相轉化

    //將字符串轉化成Drawable
    public synchronized static Drawable StringToDrawable(String icon) {
        if (icon == null || icon.length() < 10)
            return null;
        byte[] img = Base64.decode(icon.getBytes(), Base64.DEFAULT);
        Bitmap bitmap;
        if (img != null) {
            bitmap = BitmapFactory.decodeByteArray(img, 0, img.length);
            @SuppressWarnings("deprecation")
            Drawable drawable = new BitmapDrawable(bitmap);

            return drawable;
        }
        return null;
    }

    //將drawable轉化成字符串
    public synchronized static String DrawableToString(Drawable drawable) {
        if (drawable != null) {
            Bitmap bitmap = Bitmap
                    .createBitmap(
                            drawable.getIntrinsicWidth(),
                            drawable.getIntrinsicHeight(),
                            drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                                    : Bitmap.Config.ARGB_8888);
            Canvas canvas = new Canvas(bitmap);
            drawable.setBounds(0, 0, drawable.getIntrinsicWidth(),
                    drawable.getIntrinsicHeight());
            drawable.draw(canvas);
            int size = bitmap.getWidth() * bitmap.getHeight() * 4;

            // 創建一個字節數組輸出流,流的大小為size
            ByteArrayOutputStream baos = new ByteArrayOutputStream(size);
            // 設置位圖的壓縮格式，質量為100%，並放入字節數組輸出流中
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
            // 將字節數組輸出流轉化為字節數組byte[]
            byte[] imagedata = baos.toByteArray();

            return Base64.encodeToString(imagedata, Base64.DEFAULT);
        }
        return " ";
    }