Android : GridView adapter getItemID settings

I am filling a GridView with a set of images from MediaStore.Images.Thumbnails._ID and MediaStore.Images.Thumbnails.IMAGE_ID but get a diffent picture showing in the setOnItem ClickListener when shown in the Imageview in SecondActivity. (I am relatively new to cursors and databases so may be missing a few basics here!):

final Intent intent = new Intent(this, SecondActivity.class);
GridView gridView = (GridView) findViewById(R.id.gridview);
gridView.setAdapter(new ImageAdapter(this));
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    intent.putExtra("picture",position);
    startActivity(intent);

I am not getting the correct "position" and understand that I must modify the class below

   //---Returns the ID of one item---
   public long getItemId(int position) {
       return position;
   }

but I do not know how to get a reference to it or what to put there. The second intent always shows a different image from the clicked one.

int imageID    = getIntent().getIntExtra("picture",0);
imageView.setImageURI(
            Uri.withAppendedPath(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,  + imageID)
);