How to use offer() in android ConcurrentLinkedQueue?

Before getting into an example, we should know what ConcurrentLinkedQueue is, it is an unbounded queue based on linked nodes. Multiple threads can access queue elements with safety. Elements travel based on queue strategy as FIFO and elements going to insert from a tail. It does not allow null values.

This example demonstrates about How to use offer() in android ConcurrentLinkedQueue

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.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:gravity="center"
   android:layout_height="match_parent"
   tools:context=".MainActivity"
   android:orientation="vertical">
   <TextView
      android:id="@+id/actionEvent"
      android:textSize="40sp"
      android:layout_marginTop="30dp"
      android:layout_width="wrap_content"
      android:layout_height="match_parent" />
</LinearLayout>

In the above code, we have taken a text view to show ConcurrentLinkedQueue elements.

Step 3 − Add the following code to src/MainActivity.java

package com.example.myapplication;
import android.os.Build;
import android.os.Bundle;
import android.support.annotation.RequiresApi;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;
import java.util.concurrent.ConcurrentLinkedQueue;
public class MainActivityextends AppCompatActivity {
   ConcurrentLinkedQueue concurrentLinkedQueue;
   String head;
   @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      concurrentLinkedQueue = new ConcurrentLinkedQueue<String>();
      final TextViewactionEvent = findViewById(R.id.actionEvent);
      concurrentLinkedQueue.add("sai");
      concurrentLinkedQueue.add("ram");
      concurrentLinkedQueue.add("krishna");
      concurrentLinkedQueue.add("prasad");
      concurrentLinkedQueue.add("ram");
      actionEvent.setText("" + concurrentLinkedQueue);
      actionEvent.setOnClickListener(new View.OnClickListener() {
         @Override
         public void onClick(View v) {
            concurrentLinkedQueue.offer("prasad");
            actionEvent.setText("" +concurrentLinkedQueue);
         }
      });
   }
}

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from an android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

Now to click on textview, it will give the result as shown below −

Click  here  to download the project code