Help Saving an bitmap using OutputStream on Android, following the Activities onPause.

Question

In my activite's onCreate i have

  public void onCreate() {
    try
    {
        FIStream = super.openFileInput("4.png");
        MyImagePort.load(FIStream);
        FIStream.close();   
        FIStream = null;
    } catch (FileNotFoundException e) {
        Log.w("spriter","File not found");
    } catch (IOException e) {
        e.printStackTrace();
    }
    }

Which seems to work fine. But then my Activity Overrides onPause..

@Override
    public void onPause(){
    super.onPause();
    DoAutoSave();
}

private void DoAutoSave() {
    try {
    FOStream = new FileOutputStream("\\sdcard\\spriter\\4.png");
    } catch (FileNotFoundException e) {
    e.printStackTrace();
    }   
  MyImagePort.SetAutoSaveFileStream(FOStream);
 }  

The problem is, FOStream above never recieves a OutputStream and is always null. what am i doing wrong please