Firebase 数据库部分列表视图

Question

我需要从 Firebase（部分列表适配器 firebase 数据库）中检索数据。 例如 Firebase 数据库。

Answer 1

我用这个适配器

public class MatcmobikraAdapter extends ArrayAdapter<MatchmobikooraModel> {

private static final String TAG = "MatchAdapter";

private LayoutInflater mInflater;
private int  mLayoutResource;
private Context mContext;
private Typeface myTypeface;

public MatcmobikraAdapter(@NonNull Context context, @LayoutRes int resource, @NonNull List<MatchmobikooraModel> objects) {
    super(context, resource, objects);

    mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    mLayoutResource = resource;
    this.mContext = context;
}

static class ViewHolder {
    ImageView team1logo, team2logo;       
    TextView team1, team2, matchtime;
    MatchmobikooraModel matchmobikooraModel;

}
@NonNull
@Override
public View getView(final int position, @Nullable View convertView, @NonNull ViewGroup parent) {

    final ViewHolder holder;

    if (convertView == null){
        convertView = mInflater.inflate(mLayoutResource, parent, false);
        holder = new ViewHolder();

        holder.matchtime = (TextView) convertView.findViewById(R.id.text_time);
        holder.team1 = (TextView) convertView.findViewById(R.id.homescore);
        holder.team2 = (TextView) convertView.findViewById(R.id.awayscore);
        holder.team1logo  = (ImageView) convertView.findViewById(R.id.homeicon);
        holder.team2logo  = (ImageView) convertView.findViewById(R.id.awayicon);
        holder.matchmobikooraModel = getItem(position);
        myTypeface = Typeface.createFromAsset(mContext.getAssets(), "bein.ttf");
        convertView.setTag(holder);
    }
    else {
        holder = (ViewHolder) convertView.getTag();
    }

       // MatchmobikooraModel matchmobikooraModel = getItem(position);//Modelmatch modelmatch = getItem(position);



        holder.team1.setText(getItem(position).getTeam1());
        holder.team1.setTypeface(myTypeface);
        holder.team2.setText(getItem(position).getTeam2());
        holder.team2.setTypeface(myTypeface);
        holder.matchtime.setText(getItem(position).getMatch_time());
        holder.matchtime.setTypeface(myTypeface);

        PicassoClient.downloadimg(mContext, getItem(position).getTeam1logo(), holder.team1logo);
        PicassoClient.downloadimg(mContext, getItem(position).getTeam2logo(), holder.team2logo);

  return convertView;
}

Answer 2

这段代码用于从 firebase 检索数据

public class CameraFragment extends Fragment {
private static final String TAG = "Match Fragment";

private ListView mListView;
private ArrayList<MatchmobikooraModel> mMatchmobikooraModels;
private MatcmobikraAdapter matcmobikraAdapter;


@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_camera, container, false);

    mListView = (ListView) view.findViewById(R.id.listMatch3);

    mMatchmobikooraModels = new ArrayList<>();



    getmobara();
    return view;
}

private void getmobara(){
    DatabaseReference myRef = FirebaseDatabase.getInstance().getReference().child("match").child("leagues");
    Query query = myRef;

    query.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {

            for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()){
                DataSnapshot dataSnapshot2 = dataSnapshot1.child("league_matches");

                for (DataSnapshot dataSnapshot3 : dataSnapshot2.getChildren()){
                    Log.d(TAG, "found mobara time : " +dataSnapshot3.child("match_time").getValue());

                    MatchmobikooraModel matchmobikooraModel = new MatchmobikooraModel();

                    Map<String, Object> objectMap = (HashMap<String, Object>) dataSnapshot3.getValue();

                    Log.d(TAG, "found match time : " + dataSnapshot3.child("match_time").getValue());

                            // matchmobikooraModel.setMatch_id(objectMap.get("match_id").toString());
                    matchmobikooraModel.setMatch_time(objectMap.get("match_time").toString());
                    matchmobikooraModel.setTeam1(objectMap.get("team1").toString());
                    matchmobikooraModel.setTeam1logo(objectMap.get("team1logo").toString());
                    matchmobikooraModel.setTeam2(objectMap.get("team2").toString());
                    matchmobikooraModel.setTeam2logo(objectMap.get("team2logo").toString());
                    mMatchmobikooraModels.add(matchmobikooraModel);

                }
                Log.d(TAG, "onDataChange: get match count " + mMatchmobikooraModels.size());
                matcmobikraAdapter = new MatcmobikraAdapter(getActivity(), R.layout.row_game_logos, mMatchmobikooraModels);
                mListView.setAdapter(matcmobikraAdapter);
            }


        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });

}

Answer 3

public class MeetingShow extends AppCompatActivity {

  ListView listView;
  List<MeetingInfo> list;
  ProgressDialog progressDialog;
  private DatabaseReference databaseReference;
  MeetingAdapter eventAdapter;

  @Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_meeting_show);

    listView=findViewById(R.id.meetinglistview);


    list=new ArrayList<>();
    progressDialog=new ProgressDialog(this);
    progressDialog.setTitle("Fetching.... ");
    progressDialog.show();

// change according to your node detail
    databaseReference= FirebaseDatabase.getInstance().getReference("Meeting");
    databaseReference.addValueEventListener(new ValueEventListener() {
      @Override public void onDataChange(DataSnapshot dataSnapshot) {
        progressDialog.dismiss();
        MeetingInfo imageinfo=dataSnapshot.getValue(MeetingInfo.class);
        list.clear();
        for(DataSnapshot snapshot :dataSnapshot.getChildren())
        {
          MeetingInfo imageInfo=snapshot.getValue(MeetingInfo.class);
          imageInfo.setMeetingkey(snapshot.getKey());
          list.add(imageInfo);
        }
        eventAdapter =new MeetingAdapter(MeetingShow.this,R.layout.activity_meeting_format,list);
        listView.setAdapter(eventAdapter);
      }

      @Override public void onCancelled(DatabaseError databaseError) {
        Toast.makeText(MeetingShow.this, databaseError.getCode(),Toast.LENGTH_SHORT).show();

      }
    });
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
      @Override public void onItemClick(AdapterView<?> adapterView, final View view, final int i, long l) {
       // progressDialog=new ProgressDialog(MeetingShow.this);
        view.setBackgroundColor(Color.RED);


        AlertDialog.Builder alert = new AlertDialog.Builder(MeetingShow.this);

        alert.setTitle("Delete entry");
        alert.setMessage("Are you sure you want to delete?");
        alert.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {

          public void onClick(DialogInterface dialog, int which) {
//delete entry by clicking on listview item
            final MeetingInfo meetingInfo=list.get(i);
            final String selecteditem=meetingInfo.getMeetingkey();
            databaseReference.child(selecteditem).removeValue();
            Toast.makeText(MeetingShow.this,"Deleted",Toast.LENGTH_SHORT).show();
            listView.setAdapter(eventAdapter);


          }
        });
        alert.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
            view.setBackgroundColor(Color.WHITE);   }
        });
        alert.show();
      }        });
      }
      }