Android refresh a fragment list from its parent activity

Question

I have a main activity which contains the action bar with 3 menu buttons in it.

I then have a fragment within this main activity which has a list.

I would like to be able to refresh the list in the fragment from the main activity, when one of the menu buttons is clicked, or preferably just removed all the rows from the list.

Any help is appreciated.

Thanks.

public class Favourite extends SherlockFragmentActivity {

    ActionBar actionBar;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.favourite);

        actionBar = getSupportActionBar();

        actionBar.setDisplayShowTitleEnabled(false);

        BitmapDrawable bg = (BitmapDrawable)getResources().getDrawable(R.drawable.actionbar_bg);
        bg.setTileModeX(TileMode.REPEAT); 
        getSupportActionBar().setBackgroundDrawable(bg);

        getSupportActionBar().setIcon(R.drawable.favourite_title);

        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        ActionBar.Tab tabAll = actionBar.newTab();
        ActionBar.Tab tabfavs = actionBar.newTab();
        ActionBar.Tab tabhist = actionBar.newTab();
        tabAll.setText("all");
        tabfavs.setText("favs");
        tabhist.setText("hist");
        tabAll.setTabListener(new MyTabListener());
        tabfavs.setTabListener(new MyTabListener());
        tabhist.setTabListener(new MyTabListener());
        actionBar.addTab(tabAll);
        actionBar.addTab(tabfavs);
        actionBar.addTab(tabhist);


        try{

        }
        catch(Exception e)
        {
        }
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        MenuInflater inflater = getSupportMenuInflater();
        inflater.inflate(R.menu.actionbar_itemlist_favourite, menu);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch(item.getItemId()) {
                case R.id.history:
                    break;
                case R.id.favourite:
                    Intent favAct = new Intent(this, Favourite.class);
                    startActivity(favAct);
                    break;
                case R.id.delete:
                    ///I WANT TO BE ABLE TO REFRESH FRAGMENTLIST FROM HERE
                }
                return true;
    }

  }

class MyTabListener implements ActionBar.TabListener {

    public void onTabSelected(Tab tab, FragmentTransaction ft) {
        if(tab.getPosition()==0)
        {
            FavouriteAllWords frag = new FavouriteAllWords();
            ft.replace(android.R.id.content, frag);

        }
        else if(tab.getPosition()==1)
        {
            FavouriteFavWords frag = new FavouriteFavWords();
            ft.replace(android.R.id.content, frag);

        }
        else if(tab.getPosition()==2)
        {
            FavouriteHistWords frag = new FavouriteHistWords();
            ft.replace(android.R.id.content, frag);
        }
    }

    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        // TODO Auto-generated method stub

    }

    public void onTabReselected(Tab tab, FragmentTransaction ft) {
        // TODO Auto-generated method stub

    }

}

////////////////////MY LIST FRAGMENT CLASS

public class FavouriteAllWords extends ListFragment {

    ArrayAdapter<String> adapter;

    List<String> stringOfFavWords;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle saved)
    {   
        adapter = new ArrayAdapter<String>(  
                inflater.getContext(), R.layout.row, stringOfFavWords);  
                setListAdapter(adapter);  

        return super.onCreateView(inflater, group, saved);  
    }

    @Override
    public void onActivityCreated (Bundle savedInstanceState)
    {   
        super.onActivityCreated(savedInstanceState);
    }

}

Answer 1

You can easily achieve this using INTERFACE

MainActivity.java

public class MainActivity extends Activity {

    public FragmentRefreshListener getFragmentRefreshListener() {
        return fragmentRefreshListener;
    }

    public void setFragmentRefreshListener(FragmentRefreshListener fragmentRefreshListener) {
        this.fragmentRefreshListener = fragmentRefreshListener;
    }

    private FragmentRefreshListener fragmentRefreshListener;

    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        Button b = (Button)findViewById(R.id.btnRefreshFragment);

        b.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(getFragmentRefreshListener()!=null){
                    getFragmentRefreshListener().onRefresh();
                }
            }
        });


    }


    public interface FragmentRefreshListener{
        void onRefresh();
    }

}

MyFragment.java

public class MyFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = null; // some view

        /// Your Code


        ((MainActivity)getActivity()).setFragmentRefreshListener(new MainActivity.FragmentRefreshListener() {
            @Override
            public void onRefresh() {

                // Refresh Your Fragment
            }
        });


        return v;
    }
}

Answer 2

• Just make your update/refresh method public and call it from your Activity.

OR

• Use LocalBroadcastManager or EventBus to send event from your Activity, and by subscribing to this event in a Fragment - react to it and call refresh/update method.

Answer 3

Your activity can call methods in the fragment by acquiring a reference to the Fragment.

(1) Provide a tag when you add your fragment.

transaction.add(R.id.fragment_container, myFragment, "myfragmentTag");

(2) In your hosting activity you can find the fragment and have access to it's methods.

FragmentManager fm = getSupportFragmentManager();
myFragment f = (myFragment) fm.findFragmentByTag("myfragmentTag");
f.refreshAdapter()

(3) refreshAdapter() could now call adapter.notifyDataSetChanged().

This is one of the recommended ways to communicate up to a fragment. The interface implementation is mainly for communicating back to the activity.

Answer 4

Biraj Zalavadia's answer is 100% right, you will call nay fragment methods from using interface.... this interface methods is running without error...

use this in MainActivity above oncreate private FragmentRefreshListener fragmentRefreshListener;

public FragmentRefreshListener getFragmentRefreshListener() {
    return fragmentRefreshListener;
}

public void setFragmentRefreshListener(
        FragmentRefreshListener fragmentRefreshListener) {
    this.fragmentRefreshListener = fragmentRefreshListener;
}

inside of Activity

private void refreshcall(String result2) {
    // TODO Auto-generated method stub
    if (getFragmentRefreshListener() != null) {
        getFragmentRefreshListener().onRefresh(result2);
    }

}

and put this in needed Fragment

private FragmentRefreshListener fragmentRefreshListener;

    public FragmentRefreshListener getFragmentRefreshListener() {
        return fragmentRefreshListener;
    }

    public void setFragmentRefreshListener(
            FragmentRefreshListener fragmentRefreshListener) {
        this.fragmentRefreshListener = fragmentRefreshListener;
    }

Answer 5

Communicating with Other Fragments

http://developer.android.com/training/basics/fragments/communicating.html

This can also be used to communicate between an Activity and a Fragment.

Answer 6

When you click on ActionBar any Button then call interface to refresh the ListFragment. Because in java interface is used for inter-communication.