Nsryjdtyk

I am developing an app for finding nearby donor. If any user needs blood they can post for blood..In notification fragment user will see who needs which blood? I want to make list view from notification table using firebaseAdapter but i want an user will not his/her notification..that's why in populateView() i checked if the id of finder(who post for blood) and the id of the currrent user matches or not..if matches i make the parrent layout of the layout that is using for listview VIEW.GONE...that helps to hide currrent user's notification but items remain empty in the list...that's why next items are added after that empty items..How can i remove that empty items or hide current user's notifications

Notification Fragment

package com.blz.prisoner.lifeshare;





import android.content.Intent;

import android.graphics.Color;

import android.graphics.drawable.ColorDrawable;

import android.net.Uri;

import android.os.Bundle;

import android.os.Handler;

import android.support.annotation.NonNull;

import android.support.annotation.Nullable;

import android.support.v4.app.Fragment;

import android.view.LayoutInflater;

import android.view.Menu;

import android.view.MenuInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.AdapterView;

import android.widget.LinearLayout;

import android.widget.TextView;

import android.widget.Toast;



import com.baoyz.swipemenulistview.SwipeMenu;

import com.baoyz.swipemenulistview.SwipeMenuCreator;

import com.baoyz.swipemenulistview.SwipeMenuItem;

import com.baoyz.swipemenulistview.SwipeMenuListView;

import com.firebase.client.Firebase;

import com.firebase.ui.database.FirebaseListAdapter;

import com.firebase.ui.database.FirebaseListOptions;

import com.google.firebase.auth.FirebaseAuth;

import com.google.firebase.database.DatabaseReference;

import com.google.firebase.database.FirebaseDatabase;

import com.google.firebase.database.Query;



import java.text.DecimalFormat;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Calendar;

import java.util.Date;

import java.util.List;





/**

 * A simple {@link Fragment} subclass.

 */

public class NotificationsFragment extends Fragment {



    SwipeMenuListView listView;

    FirebaseListAdapter adapter;

    TextView notif_text,time_text,address_text,distance_text,phone;



    LinearLayout notification_linear;

    Query query;

    View rootView;



    FirebaseListOptions<NotificationData> options;



   /* List<Integer> list_position = new ArrayList<Integer>();*/



    FirebaseAuth firebaseAuth;

    GPSTracker gps;

    String lattitude,longtitude,phoneCall;

    double latt1,longt1,latt2,longt2;





    public NotificationsFragment() {

        // Required empty public constructor

    }



    @Override

    public void onCreate(@Nullable Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);



        setHasOptionsMenu(true);

    }





    @Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        // Inflate the layout for this fragment





        rootView =inflater.inflate(R.layout.fragment_donors, container, false);



        listView = rootView.findViewById(R.id.listview);



        firebaseAuth = FirebaseAuth.getInstance();

        gps = new GPSTracker(getActivity());



        latt1 = gps.getLatitude();

        longt1 = gps.getLongitude();



        query =FirebaseDatabase.getInstance().getReference().child("Notifications");



        setQuery(query);









        SwipeMenuCreator creator = new SwipeMenuCreator() {



            @Override

            public void create(SwipeMenu menu) {



                // create "delete" item

                SwipeMenuItem deleteItem = new SwipeMenuItem(getActivity());

                // set item background

                deleteItem.setBackground(new ColorDrawable(Color.rgb(0xF9,

                        0x3F, 0x25)));

                // set item width

                deleteItem.setWidth(170);

                // set a icon

                deleteItem.setIcon(R.drawable.ic_phone);

                // add to menu

                menu.addMenuItem(deleteItem);

            }

        };



        listView.setMenuCreator(creator);





        listView.setOnMenuItemClickListener(new SwipeMenuListView.OnMenuItemClickListener() {

            @Override

            public boolean onMenuItemClick(int position, SwipeMenu menu, int index) {

                switch (index) {

                    case 0:

                        // open

                        String s ="tel:"+phoneCall;



                        Intent intent = new Intent(Intent.ACTION_DIAL);

                        intent.setData(Uri.parse(s));

                        startActivity(intent);







                        break;

                }

                // false : close the menu; true : not close the menu

                return false;

            }

        });



        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override

            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

                TextView txt = view.findViewById(R.id.phone);



                phoneCall = txt.getText().toString();

                Toast.makeText(getActivity(),listView.getItemAtPosition(position).toString(),Toast.LENGTH_SHORT).show();

            }

        });



        /*

        }*/







        //

        return rootView;

    }





    @Override

    public void onStart() {

        super.onStart();

        adapter.startListening();

    }



    @Override

    public void onStop() {

        super.onStop();

        adapter.stopListening();

    }



    @Override

    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {

        super.onCreateOptionsMenu(menu, inflater);

        inflater.inflate(R.menu.blood_group_menu,menu);

    }



    public void setQuery(Query query){

        /*list_position.clear();*/







        options = new FirebaseListOptions.Builder<NotificationData>()

                .setLayout(R.layout.notificatiion_list)

                .setQuery(query,NotificationData.class)

                .build();



        adapter = new FirebaseListAdapter(options) {



            @Override

            protected void populateView(@NonNull View v, @NonNull Object model, int position) {

                NotificationData notif = (NotificationData) model;



                notification_linear = v.findViewById(R.id.notification_linear);











                if (notif.getUserid().toString().equals(firebaseAuth.getUid())){

                    notification_linear.setVisibility(View.GONE);

                    /*list_position.add(position);*/

                    /*Toast.makeText(getActivity(),Integer.toString(position),Toast.LENGTH_SHORT).show();*/

                }







                else if(!notif.getUserid().toString().equals(firebaseAuth.getUid())){

                    listView.setVisibility(View.VISIBLE);



                    notif_text = v.findViewById(R.id.notif_text);

                    time_text = v.findViewById(R.id.time_text);

                    address_text = v.findViewById(R.id.address_text);

                    distance_text = v.findViewById(R.id.distance_text);



                    phone = v.findViewById(R.id.phone_text);





                    String txt;

                    txt = notif.getFullName() + " Needs " + notif.getBloodGroup() + "Blood";







                    notif_text.setText(txt);

                    address_text.setText(notif.getAddress().toString());





                    phone.setText(notif.getPhone().toString());



                    lattitude = notif.getLattitude();

                    longtitude = notif.getLongitude();



                    latt2 = Double.parseDouble(lattitude);

                    longt2 = Double.parseDouble(longtitude);



                    float dist;

                    float result = new float[1];



                    android.location.Location.distanceBetween(latt1,longt1,latt2,longt2, result);



                    if(result.length>=1){



                        DecimalFormat df = new DecimalFormat();

                        df.setMaximumFractionDigits(2);

                        dist = result[0]/1000;

                        /*Toast.makeText(MainActivity.this,Float.toString(dist),Toast.LENGTH_LONG).show();*/

                        distance_text.setText(df.format(dist) + " Km");

                    }



                    Calendar calendar = Calendar.getInstance();

                    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd-MM-yy HH:mm:ss");



                    String dateStop = simpleDateFormat.format(calendar.getTime());

                    String dateStart = notif.getDateTime();



                    Date d1 = null;

                    Date d2 = null;



                    try {

                        d1 = simpleDateFormat.parse(dateStart);

                        d2 = simpleDateFormat.parse(dateStop);



                        //in milliseconds

                        long diff = d2.getTime() - d1.getTime();



                       /* long diffSeconds = diff / 1000 % 60;*/

                        long diffMinutes = diff / (60 * 1000) % 60;

                        long diffHours = diff / (60 * 60 * 1000) % 24;

                        long diffDays = diff / (24 * 60 * 60 * 1000);



                        if(diffMinutes<1){

                            time_text.setText("Now");

                        }



                        else if(diffMinutes>=1 && diffMinutes<60){

                            time_text.setText(Long.toString(diffMinutes) + " Minutes Ago");



                        }



                        else if(diffMinutes>=60 && diffHours<24){

                            time_text.setText(Long.toString(diffHours) + " Hours Ago");

                        }



                        else if(diffHours>=24){

                            time_text.setText(Long.toString(diffDays) + " Days Ago");

                        }





                    } catch (Exception e) {

                        e.printStackTrace();

                    }







                }



            }

        };



        listView.setAdapter(adapter);

        adapter.startListening();









    }





}

notification_fragment XML

<?xml version="1.0" encoding="utf-8"?>

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".NotificationsFragment">



    <com.baoyz.swipemenulistview.SwipeMenuListView

        android:id="@+id/listview"

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:visibility="invisible">



    </com.baoyz.swipemenulistview.SwipeMenuListView>



</FrameLayout>

notificatiion_list layout is used to create list view

notificatiion_list XML

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:app="http://schemas.android.com/apk/res-auto"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    android:paddingStart="15dp"

    android:paddingLeft="15dp"

    android:paddingEnd="10dp"

    android:paddingRight="10dp"

    android:paddingBottom="15dp"

    android:background="@drawable/profile_backgroud"

    tools:context=".MainActivity">



    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="horizontal">



        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="Bishal Imtiaz Needs AB+ Blood"

            android:layout_weight="8"/>



        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="20 minutes"

            android:layout_weight="1"/>

        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="Ago"

            android:layout_weight="1"/>

    </LinearLayout>



    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content">

        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="20 minutes"/>

        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="Ago"/>

    </LinearLayout>





</LinearLayout>

NotificationData class is used to store firebase data

NotificationData Class JAVA

package com.blz.prisoner.lifeshare;



public class NotificationData {



    String fullName;

    String dateTime;

    String bloodGroup;

    String phone;

    String lattitude;

    String longitude;

    String address;



    public String getUserid() {

        return userid;

    }



    public void setUserid(String userid) {

        this.userid = userid;

    }



    String userid;



    public String getLattitude() {

        return lattitude;

    }



    public void setLattitude(String lattitude) {

        this.lattitude = lattitude;

    }



    public String getLongitude() {

        return longitude;

    }



    public void setLongitude(String longitude) {

        this.longitude = longitude;

    }



    public NotificationData(String fullName, String dateTime, String bloodGroup, String phone, String address, String lattitude, String longitude,String userid) {

        this.fullName = fullName;

        this.dateTime = dateTime;

        this.bloodGroup = bloodGroup;

        this.phone = phone;

        this.lattitude = lattitude;



        this.longitude = longitude;

        this.address = address;

        this.userid = userid;

    }



    public NotificationData(){

        //empty constructor

    }







    public String getFullName() {

        return fullName;

    }



    public void setFullName(String fullName) {

        this.fullName = fullName;

    }



    public String getDateTime() {

        return dateTime;

    }



    public void setDateTime(String dateTime) {

        this.dateTime = dateTime;

    }



    public String getAddress() {

        return address;

    }



    public void setAddress(String address) {

        this.address = address;

    }



    public String getBloodGroup() {

        return bloodGroup;



    }



    public void setBloodGroup(String bloodGroup) {

        this.bloodGroup = bloodGroup;

    }



    public String getPhone() {

        return phone;

    }



    public void setPhone(String phone) {

        this.phone = phone;

    }

}

Here is the screenshot of outputs
enter image description here

i don't want those empty items above..i need solution..if you have any alternative idea to do so tell me since i am noob developer :(

When using a FirebaseListAdapter, populateView() method is called for every child at that location. This means you are making a view for every child. Unfortunately, you cannot choose whether or not a view will appear for that item.

It looks like you're assuming that your if statement that you are using in the populateView() method will skip over those items but what is actually happening is that you're simply allowing an empty view to occupy that spot in your list.

What can you do instead to solve this issue, is to create a query that generates only the items of interest to your list. This means you'll have to tell Firebase to filter for children that meet your criteria.

There is also another approach in which you'll have to read the entire contents of the location, manually filter out the items you don't want to have in your list, and build a a new list of items you do want. You can then build an Adapter with that list, and it can then become the input to a ListView (or better, a RecyclerView).