Android – How to Change the Color of Alternate Rows in RecyclerView

RecyclerView is an essential ViewGroup used in Android to display a list of items. It provides a flexible and highly customizable way of implementing a list that can be presented as a grid or a list. In this project, we will be working with RecyclerView to change the color of alternate rows. Typically, all items in a RecyclerView have the same color, which can be monotonous and unappealing. By alternating the row colors, we can provide a better visual experience to the user. To achieve this, we will assign a LightGrey color to the items at even positions and a White color to those at odd positions. This simple trick will help us customize our RecyclerView and enhance the user interface. The image below illustrates what we will accomplish in this project.

Step-by-Step Implementation:

Step 1: Create a New Project in Android Studio

To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio. Note that select Kotlin as the programming language.

Step 2: Add buildFeatures to build.gradle (Module:app)

Since in this project, we used ViewBinding so we have to set ViewBinding=True. Navigate to Gradle Scripts > build.gradle (Module:app) and add the Below buildFeatures section under the android section in the build.gradle (Module:app).

buildFeatures 
{
     viewBinding = true
}

Android Section

android {
   namespace 'com.example.geeksforgeeks'
   compileSdk 32
   defaultConfig {
       applicationId "com.example.geeksforgeeks"
       minSdk 21
       targetSdk 32
       versionCode 1
       versionName "1.0"
       testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
   }
   buildTypes {
       release {
           minifyEnabled false
           proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
       }
   }
   compileOptions {
       sourceCompatibility JavaVersion.VERSION_1_8
       targetCompatibility JavaVersion.VERSION_1_8
   }
   kotlinOptions {
       jvmTarget = '1.8'
   }
   buildFeatures {
       viewBinding = true
   }
}

After adding this buildFeatures section, Sync the Project.

Step 3: Change the StatusBar Color

Navigate to app > res > values > themes > themes.xml and add the below code under the style section in the themes.xml file.

<item name="android:statusBarColor" tools:targetApi="l">#308d46</item>

Step 4: Working with activity_main.xml

Navigate to the app > res > layout > activity_main.xml and add the below code to the activity_main.xml file. Below is the code for the activity_main.xml file. The activity_main.xml represents the UI part of our application. It includes one RecyclerView on which our list of items is displayed. Comments are added inside the code for a better understanding of the Code.

XML

<?xml version="1.0" encoding="utf-8"?>
<!--Here we Used ConstraintLayout for our project -->
<androidx.constraintlayout.widget.ConstraintLayout
    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">

   <!--RecyclerView -->
   <androidx.recyclerview.widget.RecyclerView
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:id="@+id/rvItemsList"/>

</androidx.constraintlayout.widget.ConstraintLayout>

Step 5: Creating a layout for RecyclerView

Here we have to create a layout for our RecyclerView to display our items. Navigate to app > res > layout then Create a new layout resource file and name it items_row.xml. It includes three Text Views for displaying the Name and Emails of the Employees. Comments are added inside the code for a better understanding of the Code.

items_row.xml:

XML

<?xml version="1.0" encoding="utf-8"?>
<!--LinearLayout orientation horizontal -->
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/llMain"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center_vertical"
    android:orientation="horizontal"
    android:padding="10dp">

    <!--TextView for displaying Name -->
    <TextView
        android:id="@+id/tvName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@android:color/black"
        android:textSize="20sp"
        tools:text="Name" />
    <!--TextView for displaying ":" -->
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text=" : "
        android:textSize="20dp"
        android:textStyle="bold" />

    <!--TextView for displaying Email -->
    <TextView
        android:id="@+id/tvEmail"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:textColor="#454545"
        android:textSize="16sp"
        tools:text="Email" />

</LinearLayout>

Step 6: Creating Employee Model

In this step, we are going to create an employee model for our RecyclerView. It Contains the Employee’s Name and Employee email Id.  Below is the code for the Employee model. Navigate to app >java > your package name >  Create a Kotlin data class named it Employee.kt.

Employee.kt:

Kotlin

package com.example.geeksforgeeks
// Employee model
data class Employee(
    val name:String, // name of the employee
    val email:String // email of the employee
)

Java

package com.example.geeksforgeeks;

// Employee model
public class Employee {
    private String name; // name of the employee
    private String email; // email of the employee

    public Employee(String name, String email) {
        this.name = name;
        this.email = email;
    }

    public String getName() {
        return name;
    }

    public String getEmail() {
        return email;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}

Step 7: Creating Employee ArrayList

In this step, we are going to prepare the List of employees with the employee name and employee email. Below is the code for Creating and adding data to the ArrayList. Comments are added inside the code for a better understanding of the Code. Navigate to app > java >your package name > Create a Kotlin Object named Constants.

Constants.kt:

Kotlin

package com.example.geeksforgeeks

object Constants {
    // This Method create an employee
      // Arraylist and return the Arraylist
    fun getEmployeeData():ArrayList<Employee>{
        // create an arraylist of type employee class
        val employeeList=ArrayList<Employee>()
        val emp1=Employee("Chinmaya Mohapatra","chinmaya@gmail.com")
        employeeList.add(emp1)
        val emp2=Employee("Ram prakash","ramp@gmail.com")
        employeeList.add(emp2)
        val emp3=Employee("OMM Meheta","mehetaom@gmail.com")
        employeeList.add(emp3)
        val emp4=Employee("Hari Mohapatra","harim@gmail.com")
        employeeList.add(emp4)
        val emp5=Employee("Abhisek Mishra","mishraabhi@gmail.com")
        employeeList.add(emp5)
        val emp6=Employee("Sindhu Malhotra","sindhu@gmail.com")
        employeeList.add(emp6)

        return  employeeList
    }
}

Java

package com.example.geeksforgeeks;

import java.util.ArrayList;

public class Constants {
    // This Method create an employee
    // Arraylist and return the Arraylist
    public static ArrayList<Employee> getEmployeeData() {
        // create an arraylist of type employee class
        ArrayList<Employee> employeeList = new ArrayList<Employee>();
        Employee emp1 = new Employee("Chinmaya Mohapatra", "chinmaya@gmail.com");
        employeeList.add(emp1);
        Employee emp2 = new Employee("Ram prakash", "ramp@gmail.com");
        employeeList.add(emp2);
        Employee emp3 = new Employee("OMM Meheta", "mehetaom@gmail.com");
        employeeList.add(emp3);
        Employee emp4 = new Employee("Hari Mohapatra", "harim@gmail.com");
        employeeList.add(emp4);
        Employee emp5 = new Employee("Abhisek Mishra", "mishraabhi@gmail.com");
        employeeList.add(emp5);
        Employee emp6 = new Employee("Sindhu Malhotra", "sindhu@gmail.com");
        employeeList.add(emp6);

        return employeeList;
    }
}

Step 8: Creating Adapter for our RecyclerView

As we know for every RecycleView we need an Adapter class.  and Implement the Three member functions.

• onCreateViewHolder: Here we have to connect the layout resource file that we are for our RecyclerView. 
• onBindViewHolder: Here we have to bind our items to the data source.
• getItemCount: Here we have to return the length of our ArrayList 

Here we are going to implement the main logic to change the color of the alternate Row item. In the onBindViewHolder method we are going to check if the position is Even we assign Light grey color to that item and if the position is odd then we going to assign a white color to the item.

if (position % 2 == 0) {
           holder.llMain.setBackgroundColor(
               ContextCompat.getColor(
                   holder.itemView.context,
                   R.color.colorLightGray
               )
           )
       } else {
           holder.llMain.setBackgroundColor(ContextCompat.getColor(context, R.color.colorWhite))
       }

Navigate to app > java >your package name > Create a Kotlin Object named as ItemAdapter.Below is the code for the ItemAdapter class. Comments are added inside the code for a better understanding of the Code.

ItemAdapter.kt:

Kotlin

package com.example.geeksforgeeks

import android.view.LayoutInflater
import android.view.ViewGroup
import androidx.core.content.ContextCompat
import androidx.recyclerview.widget.RecyclerView
import com.example.geeksforgeeks.databinding.ItemsRowBinding

class ItemAdapter(
    private val items: ArrayList<Employee>
) :
    RecyclerView.Adapter<ItemAdapter.ViewHolder>() {

     // Inflates the item views which is designed in xml layout file
     // create a new
     // ViewHolder and initializes some private fields to be used by RecyclerView.
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        return ViewHolder(
            ItemsRowBinding.inflate(
                LayoutInflater.from(parent.context), parent, false
            )
        )
     }

     // Binds each item in the ArrayList to a view

     // Called when RecyclerView needs a new {@link ViewHolder}
     // of the given type to represent
     // an item.

     // This new ViewHolder should be constructed with a new
     // View that can represent the items
     // of the given type. You can either create a new
     // View manually or inflate it from an XML
     // layout file
     override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val context = holder.itemView.context
        val item = items[position]

        holder.tvName.text = item.name
        holder.tvEmail.text = item.email

        // Updating the background color according
          // to the odd/even positions in list.
        if (position % 2 == 0) {
            holder.llMain.setBackgroundColor(
                ContextCompat.getColor(
                    holder.itemView.context,
                    R.color.colorLightGray
                )
            )
        } else {
            holder.llMain.setBackgroundColor(ContextCompat.getColor(context, R.color.colorWhite))
        }

    }

    // Gets the number of items in the list
    override fun getItemCount(): Int {
        return items.size
    }

    // A ViewHolder describes an item view and metadata
    // about its place within the RecyclerView.
    class ViewHolder(binding: ItemsRowBinding) : RecyclerView.ViewHolder(binding.root) {
        // Holds the TextView that
          // will add each item to
        val llMain = binding.llMain
        val tvName = binding.tvName
        val tvEmail = binding.tvEmail
    }
}

Java

package com.example.geeksforgeeks;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.ViewGroup;

import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.RecyclerView;

import com.example.geeksforgeeks.databinding.ItemsRowBinding;

import java.util.ArrayList;

public class ItemAdapter extends RecyclerView.Adapter<ItemAdapter.ViewHolder> {

    private ArrayList<Employee> items;

    public ItemAdapter(ArrayList<Employee> items) {
        this.items = items;
    }

    // Inflates the item views which is designed in xml layout file
    // create a new
    // ViewHolder and initializes some private fields to be used by RecyclerView.
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        return new ViewHolder(
                ItemsRowBinding.inflate(
                        LayoutInflater.from(parent.getContext()), parent, false
                )
        );
    }

    // Binds each item in the ArrayList to a view

    // Called when RecyclerView needs a new {@link ViewHolder}
    // of the given type to represent
    // an item.

    // This new ViewHolder should be constructed with a new
    // View that can represent the items
    // of the given type. You can either create a new
    // View manually or inflate it from an XML
    // layout file
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        Context context = holder.itemView.getContext();
        Employee item = items.get(position);

        holder.tvName.setText(item.getName());
        holder.tvEmail.setText(item.getEmail());

        // Updating the background color according
        // to the odd/even positions in list.
        if (position % 2 == 0) {
            holder.llMain.setBackgroundColor(
                    ContextCompat.getColor(
                            holder.itemView.getContext(),
                            R.color.colorLightGray
                    )
            );
        } else {
            holder.llMain.setBackgroundColor(ContextCompat.getColor(context, R.color.colorWhite));
        }

    }

    // Gets the number of items in the list
    @Override
    public int getItemCount() {
        return items.size();
    }

    // A ViewHolder describes an item view and metadata
    // about its place within the RecyclerView.
    public static class ViewHolder extends RecyclerView.ViewHolder {
        // Holds the TextView that
        // will add each item to
        private final ViewGroup llMain;
        private final TextView tvName;
        private final TextView tvEmail;

        public ViewHolder(ItemsRowBinding binding) {
            super(binding.getRoot());
            llMain = binding.llMain;
            tvName = binding.tvName;
            tvEmail = binding.tvEmail;
        }
    }
}

Step 9: Working with MainActivity File

In this step, we are going to Get the employeelist by calling the Constants getEmployeeData() method and assign the employee list to the ItemAdapter and display the employee list.

MainActivity.kt:

Kotlin

package com.example.geeksforgeeks

import android.Manifest
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.activity.result.ActivityResultLauncher
import androidx.activity.result.contract.ActivityResultContracts
import androidx.appcompat.app.AlertDialog
import androidx.core.app.ActivityCompat
import androidx.recyclerview.widget.LinearLayoutManager
import com.example.geeksforgeeks.databinding.ActivityMainBinding

// In this project we are going to use view binding
class MainActivity : AppCompatActivity() {

      // View Binding
    var binding:ActivityMainBinding?=null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding=ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding?.root)

        // getting the employeelist
        val employelist=Constants.getEmployeeData()

        // Assign employeelist to ItemAdapter
        val itemAdapter=ItemAdapter(employelist)

          // Set the LayoutManager that
          // this RecyclerView will use.
        binding?.rvItemsList?.layoutManager = LinearLayoutManager(this)

          // adapter instance is set to the
          // recyclerview to inflate the items.
        binding?.rvItemsList?.adapter = itemAdapter
    }

}

Java

package com.example.geeksforgeeks;

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.recyclerview.widget.LinearLayoutManager;

import android.Manifest;
import android.os.Bundle;
import android.widget.Toast;

import com.example.geeksforgeeks.databinding.ActivityMainBinding;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    // View Binding
    private ActivityMainBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = ActivityMainBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

        // getting the employeelist
        ArrayList<Employee> employelist = Constants.getEmployeeData();

        // Assign employeelist to ItemAdapter
        ItemAdapter itemAdapter = new ItemAdapter(employelist);

        // Set the LayoutManager that this RecyclerView will use.
        binding.rvItemsList.setLayoutManager(new LinearLayoutManager(this));

        // adapter instance is set to the recyclerview to inflate the items.
        binding.rvItemsList.setAdapter(itemAdapter);
    }
}

Output: