how receive arraylist in fragment

Question

I need to know how to get array list using Bundle in fragment , in the examples I have seen they are using ints or strings. how to get fragments ? In my activity it was working good getting the arraylist

my updated code

public class SingleViewActivity extends FragmentActivity {
    ImageView   imageView;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_page_view);


        ArrayList<Listitem> personArrayList = new ArrayList<Listitem>();
// add some ListItem's...
        DemoObjectFragment f = DemoObjectFragment.newInstance(personArrayList);


        ViewPager    mViewPager = (ViewPager) findViewById(R.id.pager);
        imageView = (ImageView) findViewById(R.id.funnyimage);
        Bundle bundle = getIntent().getExtras();
        Log.d("s","singleview");
        mViewPager.setAdapter(mDemoCollectionPagerAdapter);


/*
        DemoCollectionPagerAdapter      mDemoCollectionPagerAdapter =      new DemoCollectionPagerAdapter( getSupportFragmentManager());
        ViewPager    mViewPager = (ViewPager) findViewById(R.id.pager);
           imageView = (ImageView) findViewById(R.id.funnyimage);
        Bundle bundle = getIntent().getExtras();
        Log.d("s","singleview");
        mViewPager.setAdapter(mDemoCollectionPagerAdapter);*/

    /*  if (savedInstanceState == null) {
            // During initial setup, plug in the details fragment.
            MyFragment myrag = new MyFragment();
            myrag.setArguments(getIntent().getExtras());
            getSupportFragmentManager().beginTransaction().add(android.R.id.content, myrag).commit();
        }
*/
    }

---

        // Since this is an object collection, use a FragmentStatePagerAdapter,
        // and NOT a FragmentPagerAdapter.

        public class DemoCollectionPagerAdapter extends FragmentStatePagerAdapter {
            public static final String ARG_OBJECT = "Person_List";

            public DemoCollectionPagerAdapter(FragmentManager fm, ArrayList<Listitem> personArrayList)
            {
                super(fm);
                Log.d("s","adapterview");
            }

            @Override
            public Fragment getItem(int i) {

                Fragment fragment = new DemoObjectFragment();
                Bundle args = new Bundle();
                // Our object is just an integer :-P
                args.putInt(DemoObjectFragment.ARG_PERSON_LIST, i + 1);
                fragment.setArguments(args);
                return fragment;
            }

            @Override
            public int getCount() {
                return 100;
            }

            @Override
            public CharSequence getPageTitle(int position) {
                return "OBJECT " + (position + 1);
            }
        }

---

// Instances of this class are fragments representing a single
// object in our collection.
public class DemoObjectFragment extends Fragment {
    public static final String ARG_PERSON_LIST = "Person_List";

    private ArrayList<Listitem> items;

    public  DemoObjectFragment newInstance(ArrayList<Listitem> items) {
        DemoObjectFragment f = new DemoObjectFragment();
        Bundle args = new Bundle();
        args.putParcelableArrayList(ARG_PERSON_LIST, items);
        f.setArguments(args);
        return f;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bundle args = getArguments();
        if (args.containsKey(ARG_PERSON_LIST)) {
            // UNTESTED: probably will need to cast this
            this.items = args.getParcelableArrayList(ARG_PERSON_LIST);
        } else { // avoid the NullPointerException later by initializing the list
            this.items = new ArrayList<Listitem>();
        }
        // use this.items as you wish, but it will be empty if you didn't set the Bundle argument correctly
    }
}
            @Override
            public View onCreateView(LayoutInflater inflater,
                                     ViewGroup container, Bundle savedInstanceState) {
                // The last two arguments ensure LayoutParams are inflated
                // properly.

                View rootView = inflater.inflate(
                        R.layout.fragment_collection_object, container, false);
              //  Bundle args = getArguments();
             //   ((TextView) rootView.findViewById(R.id.text1)).setText(Integer.toString(args.getInt(ARG_OBJECT)));
                Bundle args= new Bundle();



                ArrayList<Listitem> personArrayList = args.getParcelableArrayList("Person_List");
                System.out.print(personArrayList);

                System.out.print("here1");

                if (personArrayList != null && !personArrayList.isEmpty()) {
                    for (Listitem person : personArrayList) {
                        Picasso.
                                with(getActivity()).
                                load(person.url)
                                .placeholder(R.drawable.logo)
                                .fit()
                                .noFade()
                                .into(imageView);
                        Log.i("PersonsActivity",String.valueOf(person.url));
                    }
                }
                return rootView;
            }
        }
    }

---

I have 2 errors now :

for newInstance as I mentioned before I cannot refer to not static .

and I am getting error now for picasso

edit 3

Answer 1

This is a good start for what you are looking for and assumes you have correctly implemented Parcelable for the ListItem class.

Somewhere in your Activity

ArrayList<ListItem> personArrayList = new ArrayList<ListItem>();
// add some ListItem's...
DemoObjectFragment f = DemoObjectFragment.newInstance(personArrayList);

From the top of your Fragment class (note: it is not a static class)

public class DemoObjectFragment extends Fragment {
    public static final String ARG_PERSON_LIST = "Person_List";

    private ArrayList<ListItem> items;

    public static DemoObjectFragment newInstance(ArrayList<ListItem> items) {
        DemoObjectFragment f = new DemoObjectFragment();
        Bundle args = new Bundle();
        args.putParcelableArrayList(ARG_PERSON_LIST, items);
        f.setArguments(args);
        return f;
   }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bundle args = getArguments();
        if (args.containsKey(ARG_PERSON_LIST)) {
            // UNTESTED: probably will need to cast this
            this.items = args.getParcelableArrayList(ARG_PERSON_LIST);
        } else { // avoid the NullPointerException later by initializing the list
            this.items = new ArrayList<ListItem>();
        }
        /*
        * use this.items as you wish, but 
        * it will be empty if you didn't set the 
        * Bundle argument correctly
        */
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(
            R.layout.fragment_collection_object, container, false);

        ImageView imageView = (ImageView) rootView.findViewById(R.id.imageView);

        Log.i("DemoObjectFragment", "Inside onCreateView");

        if (this.items.isEmpty()) {
            Log.i("DemoObjectFragment", "Warning: There are no items!");
        }

        if (this.items != null) {
            for (Listitem person : items) {
                Picasso.with(getActivity())
                    .load(person.url)
                    .placeholder(R.drawable.logo)
                    .fit()
                    .noFade()
                    .into(imageView);
                Log.i("DemoObjectFragment", "Person URL: " + String.valueOf(person.url));
            }
        } else {
            Log.i("DemoObjectFragment", "Oh no! items is null!");
        }
        return rootView;
    }
}

Answer 2

From what I see the fragment has no way of knowing what personArrayList you are referring to. Usually you pass the list as an extra argument in the newInstance method (step 1), save it in the bundle (step 2) and then retrieve it from the bundle in onCreate (step 3).

To fix you code you would have to either initialize the list with a new ArrayList(), but it would be empty in that case, or do as I said above (you're just missing step 1, so you're almost done).