我有一个有三个标签的活动。每个标签的一个片段。在片段布局的xml中，我有一个listview。我需要初始化此列表视图并使用来自firebase的数据填充它。我怎么能这样做？
我的活动代码是
public class AccountActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_account);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startActivity(new Intent(AccountActivity.this,AddLeaveActivity.class));
}
});
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if(getArguments().getInt(ARG_SECTION_NUMBER) == 1){
View rootView = inflater.inflate(R.layout.fragment_today, container, false);
return rootView;
} else if(getArguments().getInt(ARG_SECTION_NUMBER) == 2){
View rootView = inflater.inflate(R.layout.fragment_tomorrow, container, false);
return rootView;
} else {
View rootView = inflater.inflate(R.layout.fragment_dayafter, container, false);
return rootView;
}
//View rootView = inflater.inflate(R.layout.activity_account, container, false);
//TextView textView = (TextView) rootView.findViewById(R.id.section_label);
//textView.setText(getString(R.string.section_format, getArguments().getInt(ARG_SECTION_NUMBER)));
//return rootView;
}
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
return PlaceholderFragment.newInstance(position + 1);
}
@Override
public int getCount() {
// Show 3 total pages.
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "TODAY";
case 1:
return "TOMORROW";
case 2:
return "DAY AFTER";
}
return null;
}
}
}
我的fragment.java是
public class TodayFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private OnFragmentInteractionListener mListener;
public TodayFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* @param param1 Parameter 1.
* @param param2 Parameter 2.
* @return A new instance of fragment TodayFragment.
*/
// TODO: Rename and change types and number of parameters
public static TodayFragment newInstance(String param1, String param2) {
TodayFragment fragment = new TodayFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
FirebaseDatabase firebaseDatabase = FirebaseDatabase.getInstance();
DatabaseReference databaseReference = firebaseDatabase.getReference();
DatabaseReference childRef;
ListView listView;
TextView textView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
textView = (TextView) getView().findViewById(R.id.todayfragmentheader);
textView.setText("Inside onCreate Fragment1");
listView = (ListView) getView().findViewById(R.id.listview);
displaylistview("20170130");
}
private void displaylistview(String str){
childRef = databaseReference.child(str);
// //databaseReference = firebaseDatabase.getReferenceFromUrl(leavedate);
FirebaseListAdapter<Leave> firebaseListAdapter = new FirebaseListAdapter<Leave>(
getActivity(),
Leave.class,
R.layout.leavelistview,
childRef
) {
@Override
protected void populateView(View v, Leave model, int position) {
((TextView)v.findViewById(R.id.lv_staffname)).setText(model.getName());
((TextView)v.findViewById(R.id.lv_type)).setText(model.getType());
((TextView)v.findViewById(R.id.lv_duration)).setText(model.getDuration());
}
};
listView.setAdapter(firebaseListAdapter);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_today, container, false);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
这里的问题不仅是数据正在填充，而且还没有设置textview的文本。但是，如果我正在使用某项活动，则会填充并列出数据。所以我猜数据检索代码是正确的。
那么在哪里可以初始化片段内的listview？