When using FragmentPagerAdapter or FragmentStatePagerAdapter, it is best to deal solely with getItem() and not touch instantiateItem() at all. The instantiateItem()–destroyItem()–isViewFromObject() interface on PagerAdapter is a lower-level interface that FragmentPagerAdapter uses to implement the much simpler getItem() interface. Before getting into this, I should clarify that if you want to switch out the actual fragments … Read more
There is another solution that does not need modifying source code of ViewPager and FragmentStatePagerAdapter, and it works with the FragmentPagerAdapter base class used by the author. I’d like to start by answering the author’s question about which ID he should use; it is ID of the container, i.e. ID of the view pager itself. … Read more
As this is a very frequently asked question, I wanted to take the time and effort to explain the ViewPager with multiple Fragments and Layouts in detail. Here you go. ViewPager with multiple Fragments and Layout files – How To The following is a complete example of how to implement a ViewPager with different fragment … Read more
How to determine when Fragment becomes visible in ViewPager You can do the following by overriding setUserVisibleHint in your Fragment: public class MyFragment extends Fragment { @Override public void setUserVisibleHint(boolean isVisibleToUser) { super.setUserVisibleHint(isVisibleToUser); if (isVisibleToUser) { } else { } } }
You need to subclass ViewPager. onTouchEvent has a lot of good things in it that you don’t want to change like allowing child views to get touches. onInterceptTouchEvent is what you want to change. If you look at the code for ViewPager, you’ll see the comment: /* * This method JUST determines whether we want … Read more
ViewPager PagerAdapter not updating the View
The main answer relies on a name being generated by the framework. If that ever changes, then it will no longer work. What about this solution, overriding instantiateItem() and destroyItem() of your Fragment(State)PagerAdapter: public class MyPagerAdapter extends FragmentStatePagerAdapter { SparseArray<Fragment> registeredFragments = new SparseArray<Fragment>(); public MyPagerAdapter(FragmentManager fm) { super(fm); } @Override public int getCount() { … Read more