android - Trying to load pdf that i could annotate/gesture on, but it doesn't respond to my gestures?

Question

I can't show the entire code, but I think that my general problem lies here:

    if (list.size() > 0 && imagelist[(int) id].isFile()) 
    {
        Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        Uri uri = Uri.fromFile(imagelist[(int) id].getAbsoluteFile());
        intent.setDataAndType(uri, "application/pdf");
        startActivity(intent);
    }

After it sends me to another activity, I'm no longer able to make gestures.

Do you know how I could keep the reference to my gesture listener when I start the new activity? Do you see anything else that I might be doing wrong?