I want to combine a default horizontal ViewPager with some kind of a [vertical ViewPager](https://stackoverflow.com/questions/13477820/android-vertical-viewpager). My approach would be that the Fragments provided by the horizontal ViewPager, are subclassing the vertical ViewPager.

```
public class SubWebViewFragment extends Fragment, VerticalViewPager {
}

```

Thus each Fragment provided by the horizontal ViewPager should at the same time act as a VerticalViewPager, building up some kind of a matrix. In addition I have to have the possibility to go to a certain page in this matrix. E.g. I want to select page 2 of the horizontal ViewPager, and of this page two I want to go to page three of the vertical ViewPager. 

```
// pseudo code
HorizontalViewPager.setCurrentItem(1, true);
activeHorizontalPage.getVerticalViewPager.setCurrentItem(2, true);

```

I'm a bit lost on how to approach this issue.