Replace ListFragment

Question

I am using a ListFragment for displaying a list from a database in my activity. I have included a search function. Unfortunately the "old" ListFragments seem to remain in the background and the ListFragments containing the result of the query are displayed on top of it. How can I avoid, that the old ListFragments are displayed?

My FragmentActivity:

private Button buttonSearch; 
    private TextView searchString; 
    public static String search = null; 
    static IShoppinglist shoppinglistManager;
    static IAktionen aktionenManager; 
    private AktionenListListFragment listFragment;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "ListFragmentActivity created"); 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.articlelist);

        shoppinglistManager = new Shoppinglist(this);
        aktionenManager = new Aktionen(this); 

        buttonSearch = (Button) findViewById(R.id.search_Button);
        buttonSearch.setOnClickListener(searchListAktionen);

        //show all entries on start
        listFragment = new AktionenListListFragment();
        getSupportFragmentManager().beginTransaction().replace(R.id.fragment_articlelist, listFragment).commit();
    }   

    OnClickListener searchListAktionen = new OnClickListener() {
        public void onClick(View v) {


            try{
                searchString = (TextView) findViewById(R.id.input_search_bezeichnung); 
                search = searchString.getText().toString().trim();
                Log.d(TAG, "search Button clicked "+search); 

                if(search.trim().length()==0){
                    search=null;
                }

                //show all entries on start
                listFragment = new AktionenListListFragment();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragment_articlelist, listFragment).commit();

            }catch(Exception ex){
                ex.printStackTrace();
            }
        }
    };

Thanks in advance,

update:

thank you for your answers. I tried to implement them, but the main problem seems to be nowthat the onCreate and onActivityCreated method in the ListFragment are called twice (as I can see in my log messages).

my new code:

@Override
    public void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "ListFragmentActivity created"); 
        super.onCreate(savedInstanceState);

        //force commit
        getSupportFragmentManager().executePendingTransactions();


        if(getSupportFragmentManager().findFragmentByTag(tag) == null) {
            setContentView(R.layout.articlelist);

            shoppinglistManager = new Shoppinglist(this);
            aktionenManager = new Aktionen(this); 

            buttonSearch = (Button) findViewById(R.id.search_Button);
            buttonSearch.setOnClickListener(searchListAktionen);
            listFragment = new AktionenListListFragment();
            getSupportFragmentManager().beginTransaction().replace(R.id.fragment_articlelist, listFragment,tag).commit();
        }else{
            Log.d(TAG, "ListFragment already exists"); 
        }
    }

I tried to set a unique tag for my ListFragment but this solution does not work.

I guess that one of the ListFragments is displayed in the background and the other is updated.

hello? dont tell me your one of those people that ask questions and then dont upvote or select the answer.. — dumamilk, Feb 13 '13 at 21:51

dumamilk · Answer 1 · 2013-02-13T19:49:58.770

2

So first you need to stop making new ListFragments everytime your list is refreshed and just have a public method in your ListFragment that the Activity can call to restart the loader with the proper parameters. Then:

In your onLoadFinished(),

you should make a new adapter with the list you want to replace it with

myAdapter = new AktionenListCustomCursorAdapter(getActivity(), myCursor);

and call:

this.getListView().setAdapter(myAdapter);

So:

    public void onLoadFinished(Loader<Cursor> mAdapter, Cursor myCursor) {
                if(myCursor!=null){
                    //getting the data from the database
                    Log.d(TAG, "search String "+AktionenListFragmentActivity.search);
                    if(AktionenListFragmentActivity.search==null){
                        myCursor = AktionenListFragmentActivity.aktionenManager.fetchAllArticles();
                    }else{
                        myCursor = AktionenListFragmentActivity.aktionenManager.fetchItemsByBezeichnung(AktionenListFragmentActivity.search);
                    }
myAdapter = new AktionenListCustomCursorAdapter(getActivity(), myCursor);
                    this.getListView().setAdapter(myAdapter);
                }
            }

Hopefully this solved your question as I understood it. If you have any questions please leave it in the comment below and I will expand my answer. If it worked for you please accept answer. :D

edited Feb 13 '13 at 19:49

answered Feb 13 '13 at 19:41

dumamilk

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My answer was half correct. but thanks for being useful dymmeh. – dumamilk Feb 13 '13 at 19:46
There you go :) You might want to fix his loading of data since he's loading it all on the main thread in onLoadFinished. – dymmeh Feb 13 '13 at 19:52
I disagree about instantiating a new adapter every time the backing data changes. You already have an adapter. Just clear it, add the new data, and call notifyDataSetChanged(). Frequently replacing the adapter is not a good solution because the list will jump back to the top every time rather than maintaining the user's scroll position. – Jon F Hancock Feb 13 '13 at 19:59
That may not matter much in this case since you are always completely replacing the data, but it is a bad habit to get into. – Jon F Hancock Feb 13 '13 at 20:02
1

See this article, which D Tran brought to my attention a few days ago. http://vikinghammer.com/2011/06/17/android-listview-maintain-your-scroll-position-when-you-refresh/ – Jon F Hancock Feb 13 '13 at 20:04

Replace ListFragment

1 Answers1