Best place to addHeaderView in ListFragment

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梦谈多话
梦谈多话 2020-12-05 02:37

I\'m having some trouble setting up my custom header in my list.

I\'m creating a ListFragment with a custom adapter. I have the list working fine, but I\'m trying t

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  • 2020-12-05 02:46

    I am currently using the following solution in my class extending ListFragment:

    1) You, in your class onActivityCreated check if your adapter (which is a class variable) is null, then instantiate it. Then, inflate the footer, for example like this:

    View footerView = View.inflate
        (getActivity(), R.layout.list_footer_loader_view, null);
    

    You do only have to do this once! The footerView and the adapter only has to be created once. I create both of these in my onActivityCreated

    Now to the "hard part", set your fragment in your onCreate to like this:

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRetainInstance(true);
    }
    

    I like to do it in the onCreate because it's not relevant for the activity. Now with the setRetainInstance(true) your fragment will not be recreated after the activity is destroyed, an event such as a screen orientation.

    Now after those rows add the footer like this:

    getListView().addFooterView(footerView);
    

    And then connect the adapter to the list:

    setListAdapter(adapter);
    

    This should be done every time the activity dies, do this in onActivityCreated.

    And one of the other important things you should generally think about when it's coming to fragments is that you don't create the fragment every time the activity's onCreate is called.

    For example do this (if your NOT using the supportpackage):

    MyFragment myFragment  = (MyFragment)
        getFragmentManager().findFragmentByTag(tag);
    if (myFragment == null) {
        myFragment = MyFragment.newInstance();
        getFragmentManager().beginTransaction().
                add(myFragment, tag).commit();
    }
    

    This will only create the fragment once, if the tag is unique for that fragment of course.

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  • 2020-12-05 02:51

    This is my solution for handling footer/header in list view. I use it in retained fragment. Adapter is initialized in renderView() method. This method can be called how many times you need (e.g. for refresh data in view) and footer/header works fine. I tested this code on Android 2,3,4.

    @Override
    public void onActivityCreated(Bundle savedInstanceState)
    {
        super.onActivityCreated(savedInstanceState);
    
        ...
    
        renderView();
    }
    
    
    @Override
    public void onDestroyView()
    {
        super.onDestroyView();
    
        // free adapter
        setListAdapter(null);
    }
    
    
    private void renderView()
    {
        // reference
        ListView listView = getListView();
    
        // adapter
        if(getListAdapter()==null)
        {
            // init adapter
            mAdapter = new MyAdapter(...);
        }
        else
        {
            // refill adapter
            // this method assign array list object to adapter and call notifyDataSetChanged()
            mAdapter.refill(...);
        }
    
        // add footer
        setListAdapter(null);
        if(listView.getFooterViewsCount()==0)
        {
            mFooterView = getActivity().getLayoutInflater().inflate(R.layout.my_footer, null);
            listView.addFooterView(mFooterView);
        }
    
        // set adapter
        setListAdapter(mAdapter);
    }
    
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  • 2020-12-05 02:55

    This solution works with screen flipping:

    In onActivityCreated():

    getListView().addHeaderView(mHeaderView);
    if (mMyAdapter == null) {
        mMyAdapter = new MyAdapter(getActivity(), null);
    }
    setListAdapter(mMyAdapter);
    

    And in onDestroyView()

    setListAdapter(null);
    
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  • 2020-12-05 02:56

    I don't know if you have solved your problem but here is a solution that worked for me:

    Do not call ListFragment.setListAdapter() in your ListFragment.onCreate(). Make sure you have a field variable that can hold the header view, maybe like:

    View mheaderView;
    

    Then in your ListFragment.onCreateView(), inflate the header View and assign it to your variable like so:

    View list_root = inflater.inflate(R.layout.fragment_list, null);
    // Get the list header - to be added later in the lifecycle
    // during onActivityCreated()
    mheaderView = inflater.inflate(R.layout.list_header, null);
    return list_root;
    

    Finally, in your ListFragment.onActivityCreated() you can now call ListFragment.getListView().addHeaderView(). Basically something like so:

    super.onActivityCreated(savedInstanceState);
    if (mheaderView != null)  this.getListView().addHeaderView(headerView);
    // Don't forget to now call setListAdapter()
    this.setListAdapter(listAdapter);
    
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  • 2020-12-05 03:01

    As short solution that worked for me:

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
    
        View headerView = getActivity().getLayoutInflater().inflate(R.layout.header, null);
        getListView().addHeaderView(headerView);
    
        ArrayAdapter<XY> mAdapter = createAdapter(); // create here your own adapter
        setListAdapter(mAdapter);
    }
    
    @Override
    public void onDestroyView() {
        super.onDestroyView();
        setListAdapter(null);
    }
    
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  • 2020-12-05 03:02

    I had some problems with header layout height, so I followed this solution:

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        setListAdapter(null);//avoid problems with orientation changes
        header = getActivity().getLayoutInflater().inflate(R.layout.row_diario_header,getListView(),false);
        getListView().addHeaderView(header);
        ArrayList<Notificacao> nots = new ArrayList<>();
    
        nots.add(new Notificacao("16/04/2015", "Test", "Erro"));
        setListAdapter(new DiarioAdapter(getActivity(), R.layout.listview_diario, nots));
    }
    

    Header is a instance of View and DiarioAdapter is a custom ArrayAdapter.

    UPDATE 1

    If you have problems with duplicate listfragment, just change FragmentTransaction ADD for REPLACE.

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