Question

如何使用微调框过滤Firebase数据库中的Recyclerview？我已经尝试做过，但是当我从微调器中选择时什么也没有发生。我想使用微调器作为类别从Firebase过滤数据。我希望有一个人可以帮助我！这是我的示例代码。

public class HistoricalSiteMenuFragment extends Fragment {
private static FirebaseDatabase firebaseDatabase;
private DatabaseReference dbChild1, dbChild2;
private RecyclerView historicalList;
private Query query;
Double latitude, longitude;
Spinner sp1;
ArrayAdapter<CharSequence> adapter1;
String selected;
View view;
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    view = inflater.inflate(R.layout.fragment_historical_site_menu, container, false);
    /*Spinner Category*/
    sp1 = (Spinner) view.findViewById(R.id.spinner);
    adapter1 = ArrayAdapter.createFromResource(getContext(), R.array.categories, android.R.layout.simple_spinner_item);
    adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    sp1.setAdapter(adapter1);
    String selected = sp1.getSelectedItem().toString();
    Bundle bundle = getArguments();

    String name = bundle.getString("name");
    String nameLower = name.toLowerCase();
    nameLower = nameLower.replace(" city", "");
    firebaseDatabase = FirebaseDatabase.getInstance();
    if (selected.equals("Historical Site")){
        dbChild1 = firebaseDatabase.getReference().child("Attractions");
        dbChild2 = dbChild1.child(nameLower);
        query = dbChild2.orderByChild("category").equalTo("historical");
        query.keepSynced(true);
        historicalList = (RecyclerView) view.findViewById(R.id.historical_list);
        historicalList.setHasFixedSize(true);
        historicalList.setLayoutManager(new LinearLayoutManager(getContext()));
    }else if (selected.equals("Ecological Site")){
        dbChild1 = firebaseDatabase.getReference().child("Attractions");
        dbChild2 = dbChild1.child(nameLower);
        query = dbChild2.orderByChild("category").equalTo("ecological");
        query.keepSynced(true);
        historicalList = (RecyclerView) view.findViewById(R.id.historical_list);
        historicalList.setHasFixedSize(true);
        historicalList.setLayoutManager(new LinearLayoutManager(getContext()));
    }else{
        dbChild1 = firebaseDatabase.getReference().child("Attractions");
        dbChild2 = dbChild1.child(nameLower);
        query = dbChild2;
        query.keepSynced(true);
        historicalList = (RecyclerView) view.findViewById(R.id.historical_list);
        historicalList.setHasFixedSize(true);
        historicalList.setLayoutManager(new LinearLayoutManager(getContext()));
    }
    return view;
}
@Override
public void onStart() {
    super.onStart();
    FirebaseRecyclerAdapter<HistoricalList,ButtonViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<HistoricalList,ButtonViewHolder>
            (HistoricalList.class,R.layout.cardview_historical,ButtonViewHolder.class,query) {
        @Override
        protected void populateViewHolder(ButtonViewHolder viewHolder, HistoricalList model, int position) {
            viewHolder.sethName(model.gethName());
            viewHolder.sethAddress(model.getAddress());
            viewHolder.sethImage(getActivity().getApplicationContext(),model.gethImage());
        }

       @Override
        public ButtonViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

            ButtonViewHolder viewHolder = super.onCreateViewHolder(parent, viewType);
            viewHolder.setOnClickListener(new ButtonViewHolder.ClickListener() {
                @Override
                public void onItemClick(View view, int position) {
                    //get data from firebase at the position clicked
                    String h_name = getItem(position).gethName();
                    String h_image = getItem(position).gethImage();
                    latitude = getItem(position).getLatitude();
                    longitude = getItem(position).getLongitude();
                    String info = getItem(position).getInfo();
                    String address = getItem(position).getAddress();

                    //pass this data to new Activity
                    final HistoricalSiteFragment hfrag = new HistoricalSiteFragment();
                    Bundle bundle = new Bundle();
                    bundle.putString("historical_name",h_name);
                    bundle.putString("historical_image",h_image);
                    bundle.putString("latitude",Double.toString(latitude));
                    bundle.putString("longitude",Double.toString(longitude));
                    bundle.putString("info",info);
                    bundle.putString("address",address);
                    hfrag.setArguments(bundle);
                    getActivity().getSupportFragmentManager().beginTransaction()
                            .replace(R.id.main_fragment_container,hfrag).addToBackStack(null).commit();
                }
            });

            return viewHolder;
        }
    };
    historicalList.setAdapter(firebaseRecyclerAdapter);
}

Answer 1

您必须使用项目选择的侦听器，如下所示-

spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
    // your code here
}

@Override
public void onNothingSelected(AdapterView<?> parentView) {
    // your code here
}

}）;

在这里，选定的项目只是处于选定位置，并过滤出您的数据。

使用Spinner过滤带有Firebase的Recyclerview

1 个答案: