Search and Sort Records in Android with Recycler View

Search and Sort Records in Recycler View in Android. In this article, we will learn how to Search and Sort Records in Recycler View in Android.

Android SDK that we are going to use here is the set of development tools to develop applications for the android platform. With the help of this, we are going to perform Search and Short action in Recycler View with Menu Buttons.

Following will be the project structure:

Step1: Getting Started With Android Studio

Create a project with Empty Activity.

Implementation library

Go to res -> Gradle Scripts -> build.gradle

implementation 'androidx.recyclerview:recyclerview:1.2.1'

RecyclerView is a list view in which we are going to display a list of items and Search and sort them.
Cards are used to populate RecyclerView.
ListView is our Adapter Class. Adapters are used to Create and Bind Cards to RecyclerView
We created an ArrayList of DBHelper class, DBHelper class consist of variable Name and Number, We also created a Backup ArrayList for Sorting.
findViewById method is used to assign objects to view. for example, we assign recyclerView class object to RecyclerView id in our XML file.
setLayoutManager
Add method is used to insert data in the array list, in this we are inserting an object of DBHelper class to our array list which consists of a String and Integer.
The setAdapter method is used to Assign Adapter to RecyclerView
onCreateOptionsMenu() is called by the Android runtime when it needs to create the options menu.
getMenuInflater method is used to inflate Menu with an XML file which is our custom Menu UI
SearchView is a widget that provides a text view through which we can search through the list
setOnQueryTextListener method will be triggered when the user clicks on the Search menu
onQueryTextChange method will change the Filter the list when every user enter text
Menu item 1 is our sort button. It’s a toggle button
setOnCheckedChangeListener will listen for a change in toggle button if the user clicks on the button the value of isChecked variable will change
If the toggle button is checked then the isChecked value will change to true, If it’s true we will add all the elements of the array list to the backup list and sort the original array list with the help of the Comparator class
Comparator class will short array list according to name
notifyDataSetChanged method will notify Recycler view for any data change in the list, listView is our adapter
In else statement, we will clear the original list and add all elements of the backup list to the original list which is not sorted

MainActivity.java

package com.example.searchandshort;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.SwitchCompat;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.CompoundButton;
import androidx.appcompat.widget.SearchView;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;

public class MainActivity extends AppCompatActivity {
   private RecyclerView recyclerView;
   private ListView listView;
   private ArrayList<DBHelper> arrayList = new ArrayList<>();
   private ArrayList<DBHelper> arrayListBackup  = new ArrayList<>();

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       recyclerView = findViewById(R.id.recycerView);
       recyclerView.setLayoutManager(new LinearLayoutManager(this));
       arrayList.add(new DBHelper(12,"Apple"));
       arrayList.add(new DBHelper(162,"Blackberry"));
       arrayList.add(new DBHelper(112,"Apricot"));
       arrayList.add(new DBHelper(132,"Avocado"));
       arrayList.add(new DBHelper(512,"Banana"));

       listView = new ListView(arrayList,this);
       recyclerView.setAdapter(listView);
   }

   @Override
   public boolean onCreateOptionsMenu(Menu menu) {
       getMenuInflater().inflate(R.menu.main_menu,menu);
       MenuItem menuItem = menu.findItem(R.id.search_bar);
       SearchView searchView = (SearchView) menuItem.getActionView();
       searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
           @Override
           public boolean onQueryTextSubmit(String query) {
               return false;
           }

           @Override
           public boolean onQueryTextChange(String newText) {
               listView.getFilter().filter(newText);
               return false;
           }
       });
       MenuItem menuItem1 = menu.findItem(R.id.menu_switch);
       SwitchCompat switchCompat =(SwitchCompat) menuItem1.getActionView();
       switchCompat.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
           @Override
           public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
               if (isChecked==true){
                   arrayListBackup.addAll(arrayList);
                   Collections.sort(arrayList, new Comparator<DBHelper>() {
                       @Override
                       public int compare(DBHelper o1, DBHelper o2) {
                           return o1.getName().compareTo(o2.getName());
                       }

                   });
                   listView.notifyDataSetChanged();
               }else {
                   arrayList.clear();
                   arrayList.addAll(arrayListBackup);
                   arrayListBackup.clear();
                   listView.notifyDataSetChanged();
               }
           }
       });
       return super.onCreateOptionsMenu(menu);
   }
}

RelativeLayout is our parent view group used to display children and align them
Layout_width tag is used to set the width of the layout, match parent will set width to its same as a parent node
Layout_height tag is used to set the height of layout, wrap content will change the height of view according to data fed into view
RecyclerView is Recycler list view whenever used scroll down the child which is scrolled up will be recycled
Layout_centerHorizontal tag will set the view centered on a horizontal plane.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
   tools:context=".MainActivity">
   <androidx.recyclerview.widget.RecyclerView
       android:id="@+id/recycerView"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_below="@+id/search_bar"
       android:layout_centerHorizontal="true"
       />

</RelativeLayout>

Step 2:Create Two new Classes ListView and DBHelper

In this class, we are creating an adapter for our Recycler View
This Adapter class will be used to populate Recycler view with user data as Card
Extend adapter class with RecyclerView.Adapter<OuterClass.InnerClass>
Extend inner class with RecyclerView.ViewHolder class
Now in the inner class, we use the constructor to assign objects to view
Override abstract method in ListAdapter class
onCreateViewHolder method is used to populate Recycler View which we Created in activity_main.xml with list_item.xml
LayoutInflater is used to inflate Recycler view with Card View
We pass an array to Recycler view and it gets populated with a card view for every entry of the array
onBindViewHolder method is used to make changes to card view child nodes
getItemCount() method will return the size of array
getFilter method will return filter object which is filtered list for Search
We are taking a backup Arraylist will all the values of nameList and Searching through the backup list
Contains method will check for if data passed into the Search box
We will get the data entered into the search box from the constraint variable
And changing the nameList Array List by first we clear the list and then add the data that matches from the backup list.

ListView.java

package com.example.searchandshort;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;

public class ListView extends RecyclerView.Adapter<ListView.ListHolder> implements Filterable {
   private ArrayList<DBHelper> namelist = new ArrayList<>();
   private Context context;
   private ArrayList<DBHelper> backUp;

   public ListView(ArrayList<DBHelper> namelist,Context context) {
       this.namelist = namelist;
       this.context = context;
       backUp = new ArrayList<>(namelist);
   }

   @NonNull
   @Override
   public ListHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
       LayoutInflater inflater = LayoutInflater.from(parent.getContext());
       View v =inflater.inflate(R.layout.list_view,parent,false);
       return new ListHolder(v);
   }

   @Override
   public void onBindViewHolder(@NonNull ListHolder holder, int position) {
   holder.textView.setText(namelist.get(position).getName());
   String s = String.valueOf(namelist.get(position).getNumber());
   holder.textView2.setText(s);
   }

   @Override
   public int getItemCount() {
       return namelist.size();
   }

   @Override
   public Filter getFilter() {
       return filter;
   }
   Filter filter = new Filter() {
       @Override
       protected FilterResults performFiltering(CharSequence constraint) {
       ArrayList<DBHelper> s = new ArrayList<>();
       if (constraint.toString().isEmpty()){
           s.addAll(backUp);
       }else {
           for (DBHelper i:backUp){
               if (i.getName().toLowerCase().contains(constraint.toString().toLowerCase())){
                   s.add(i);
               }
           }
       }
       FilterResults filterResults = new FilterResults();
       filterResults.values=s;
       return filterResults;
       }

       @Override
       protected void publishResults(CharSequence constraint, FilterResults results) {
       namelist.clear();
       namelist.addAll((ArrayList<DBHelper>)results.values);
       notifyDataSetChanged();
       }
   };
   class ListHolder extends RecyclerView.ViewHolder {
       private TextView textView;
       private TextView textView2;
       public ListHolder(@NonNull View itemView) {
           super(itemView);
           textView =(TextView) itemView.findViewById(R.id.TxtListView);
           textView2 =(TextView) itemView.findViewById(R.id.TxtListView2);
       }
   }
}

LinearLayout is our parent node LinearLayout align data or child in Horizontal or vertical orientation
TextView is a user interface element that displays text to the user
Margin tag is used to give spacing between views.

List_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
   xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:orientation="vertical"
   android:showDividers="middle"
   android:paddingBottom="20dp"
   >
   <LinearLayout
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:orientation="horizontal"
       android:padding="10dp">
       <TextView
           android:id="@+id/TxtListView"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:ems="10"
           android:layout_marginBottom="5dp"
           android:layout_marginLeft="5dp"
           android:layout_marginTop="5dp"
           />
       <TextView
           android:id="@+id/TxtListView2"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:ems="10"
           android:layout_marginBottom="5dp"
           android:layout_marginLeft="5dp"
           android:layout_marginTop="5dp"
           />
   </LinearLayout>

</LinearLayout>

Here we are using wrapper class to insert data into firebase with the help of the DBHelper constructor
The DBHelper get method is used to return the String value.

DBHelper.java

public class DBHelper {
   private int number;
   private String name;

   public DBHelper(int number, String name) {
       this.number = number;
       this.name = name;
   }

   public int getNumber() {
       return number;
   }

   public String getName() {
       return name;
   }
}

In this way, we learned how to search and sort records in Recycler View in Android.