Fool-proof way to handle Fragment on orientation change

public class MainActivity extends Activity implements MainMenuFragment.OnMainMenuItemSelectedListener { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); FragmentManager fragmentManager = getFragmentManager(); FragmentTransaction fragmentTransaction = fragmentManager .beginTransaction(); // add menu fragment MainMenuFragment myFragment = new MainMenuFragment(); fragmentTransaction.add(R.id.menu_fragment, myFragment); //add content DetailPart1 content1= new DetailPart1 (); fragmentTransaction.add(R.id.content_fragment, content1); fragmentTransaction.commit(); } public void onMainMenuSelected(String tag) { //next menu is selected replace existing fragment }

public class DetailPart1 extends Fragment { ArrayList<HashMap<String, String>> myList = new ArrayList<HashMap<String, String>>(); ListAdapter adap; ListView listview; @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); if(savedInstanceState!=null){ myList = (ArrayList)savedInstanceState.getSerializable("MYLIST_obj"); adap = new LoadImageFromArrayListAdapter(getActivity(),myList ); listview.setAdapter(adap); }else{ //get list and load in list view getlistTask = new GetALLListTasks().execute(); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View v = inflater.inflate(R.layout.skyview_fragment, container,false); return v; } @Overrid

1 Answer

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You are creating a new fragment every time you turn the screen in your activity onCreate(); But you are also maintaining the old ones with super.onCreate(savedInstanceState);. So maybe set tag and find the fragment if it exists, or pass null bundle to super.

This took me a while to learn and it can really be a pain when you are working with stuff like viewpager.

I'd recommend you to read about fragments an extra time as this exact topic is covered.

Here is an example of how to handle fragments on a regular orientation change:

Activity:

public class MainActivity extends FragmentActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        if (savedInstanceState == null) {
            TestFragment test = new TestFragment();
            test.setArguments(getIntent().getExtras());
            getSupportFragmentManager().beginTransaction().replace(android.R.id.content, test, "your_fragment_tag").commit();
        } else {
            TestFragment test = (TestFragment) getSupportFragmentManager().findFragmentByTag("your_fragment_tag");
        }
    }
}

Fragment:

public class TestFragment extends Fragment {

    public static final String KEY_ITEM = "unique_key";
    public static final String KEY_INDEX = "index_key";
    private String mTime;
    
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_layout, container, false);
        
        if (savedInstanceState != null) {
            // Restore last state
            mTime = savedInstanceS


                        
                        
                            answered 2012-11-09T10:48:59.423

Fool-proof way to handle Fragment on orientation change

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