How to get a File instance of a drawable?

Question

Below is the code that I cope with logo printing. The logo is placed in res/drawable folder. When I run the app, it throws:

java.io.FileNotFoundException: /android.resource:/com.android.test/2130837505 (No such file or directory).

Any advice?

    public  boolean printLogo()
    {
      Uri logo_path = Uri.parse("android.resource://com.android.test/" + R.drawable._logo);
      File logo = new File(logo_path.toString());
      byte[] logo_bytes = new byte[(int) logo.length()];
      System.out.print("Length:" + logo.length());
      FileInputStream fs;
      try {
          fs = new FileInputStream(logo);
          fs.read(logo_bytes);
          fs.close();
          mChatService.write(logo_bytes);
      } catch (FileNotFoundException e) {
          e.printStackTrace();
      }catch (IOException e) {
          e.printStackTrace();
      }
      return true;
    }

I try to print a bitmap via bluetooth-connected printer. `mChatService.write(Byte[] b[])` is where `OutputStream.write(Byte[] b[])` is executed. In that case, I need transfer a bitmap to a byte array. I placed the bitmap in res/drawable folder, and wrote the code above, then I encountered the FileNotFoundException just as I described. — user1437534, Jun 25 '12 at 08:20

score 10 · Accepted Answer · answered Jun 25 '12 at 08:07

10

yes you should add the resource of such type under assets or raw directory...

but if you have any limitation ans you only need byte array can try

Bitmap bmp= BitmapFactory.decodeResource(context.getResources(),
                                           R.drawable.icon_resource);

  ByteArrayOutputStream stream = new ByteArrayOutputStream();
  bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
   byte[] byteArray = stream.toByteArray();

answered Jun 25 '12 at 08:07

Dheeresh Singh

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this works but a new problem occurs. With this byteArray, a bunch of unreadable, messy code was printed instead of an the image. The image I tend to print is a PNG, the printer I use is a black white printer. Do you have any idea what the problem may be? – user1437534 Jun 25 '12 at 09:09
so far as I see, the PNG is black white. – user1437534 Jun 25 '12 at 09:10
it's png. the color is just black and white – user1437534 Jun 25 '12 at 10:02
it should work ..http://stackoverflow.com/questions/7620401/how-to-convert-byte-array-to-bitmap – Dheeresh Singh Jun 25 '12 at 10:08

score 1 · Answer 2 · answered Jun 25 '12 at 08:00

1

Put your image resources under assets folder first, then can use the AssetManager for getting InputStream from resource.

AssetManager mgr = context.getAssets(); 
FileInputStream fin = (FileInputStream)mgr.open("path/filename");

path should not contain the assets folder.

answered Jun 25 '12 at 08:00

Ron

24,175
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does the 'filename' here include the extension,e.g.,'.png'? – user1437534 Jun 25 '12 at 08:33
yes.. e.g. folder structure is `assets>images>new.png` then path will be `images/new.png` – Ron Jun 25 '12 at 08:35

How to get a File instance of a drawable?

2 Answers2