FragmentPagerAdapter - How to handle Orientation Changes?

android, android-fragments, fragmentpageradapter

Solution

Yes like you said FragmentManager handles fragments after orientation change so `getItem` in adapter is not called. But you can override method `instantiateItem()` which is called even after orientation change and cast Object to Fragment and save it in your array.

 @Override
 public Object instantiateItem(ViewGroup container, int position) {
     DataFragment fragment = (DataFragment) super.instantiateItem(container, position);
     fragments[position] = fragment;
     return fragment;
 }

Problem

I use a `FragmentPagerAdapter` containing several Fragments that need to be notified about changes to the `database`. I do this by iterating over the fragments, which implement a callback interface, and calling a `refreshData()` method. This works just fine until the device changes orientation. After an orientation change, the fragment UI does not visibly refresh even though the method call seems to work. From what I have read so far this occurs because the `FragmentPagerAdapter` handles the fragment life-cycle and the fragments that receive the callback are not the ones that are actually displayed. ``` private class DataPagerAdapter extends FragmentPagerAdapter { private DataFragment[] fragments = new DataFragment[] { new FooDataFragment(), BarDataFragment()}; public DataPagerAdapter(android.support.v4.app.FragmentManager fm) { super(fm); } @Override public Fragment getItem(int position) { return fragments[position]; } @Override public int getCount() { return fragments.length; } public DataFragment[] getFragments() { return fragments; } } protected void refreshData() { for (DataFragment dataFragment : mPagerAdapter.getFragments()) { dataFragment.refreshData(); } ``` I temporarily fixed this issue using a broadcast receiver inside each fragment, but this solution seems to be wasteful and might create memory leaks. How to I fix this properly? I use a different layout and logic in landscape mode so I want to use the newly created fragments after an orientation change.

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