

- Trending Categories
Data Structure
Networking
RDBMS
Operating System
Java
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How ListView's recycling mechanism works on Android?
This example demonstrates how ListView's recycling mechanism works on Android.
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:layout_height="match_parent" tools:context=".MainActivity"> <androidx.recyclerview.widget.RecyclerView android:id="@+id/card_recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent"/> </LinearLayout>
Step 3 − Add the following code to res/layout/card_row.xml.
<?xml version="1.0" encoding="utf-8"?> <androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="wrap_content" android:id="@+id/card" android:layout_marginTop="5dp" android:layout_marginLeft="5dp" android:layout_marginRight="5dp"> <TextView android:id="@+id/tv_country" android:layout_marginTop="10dp" android:layout_marginBottom="10dp" android:layout_gravity="center" android:textSize="18sp" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textStyle="bold" /> </androidx.cardview.widget.CardView>
Step 4 − Add the following code to src/MainActivity.java
package com.app.sample; import android.os.Bundle; import android.view.GestureDetector; import android.view.MotionEvent; import android.view.View; import android.widget.Toast; import androidx.appcompat.app.AppCompatActivity; import androidx.recyclerview.widget.LinearLayoutManager; import androidx.recyclerview.widget.RecyclerView; import java.util.ArrayList; public class MainActivity extends AppCompatActivity { private ArrayList cities; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initViews(); } private void initViews(){ RecyclerView recyclerView = (RecyclerView)findViewById(R.id.card_recycler_view); recyclerView.setHasFixedSize(true); RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getApplicationContext()); recyclerView.setLayoutManager(layoutManager); cities = new ArrayList<>(); cities.add("Mumbai"); cities.add("Chennai"); cities.add("Kochin"); cities.add("Bangalore"); cities.add("Hyderabad"); cities.add("Amaravati"); cities.add("Goa"); cities.add("Trivandram"); cities.add("Coimbatore"); cities.add("Vellore"); cities.add("Salem"); cities.add("Bhubaneswar"); cities.add(""); cities.add("Cuttack"); cities.add("Mysore"); RecyclerView.Adapter adapter = new DataAdapter(cities); recyclerView.setAdapter(adapter); recyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() { GestureDetector gestureDetector = new GestureDetector(getApplicationContext(), new GestureDetector.SimpleOnGestureListener(){ @Override public boolean onSingleTapUp(MotionEvent e) { return true; } }); @Override public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) { View child = rv.findChildViewUnder(e.getX(), e.getY()); if(child != null && gestureDetector.onTouchEvent(e)) { int position = rv.getChildAdapterPosition(child); Toast.makeText(getApplicationContext(), (Integer) cities.get(position), Toast.LENGTH_SHORT).show(); } return false; } @Override public void onTouchEvent(RecyclerView rv, MotionEvent e) { } @Override public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { } }); } }
Step 5 − Add the following code to src/DataAdapter.java
package com.app.sample; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import androidx.recyclerview.widget.RecyclerView; import java.util.ArrayList; public class DataAdapter extends RecyclerView.Adapter<DataAdapter.ViewHolder>{ private ArrayList<String> cities; public DataAdapter(ArrayList<String> countries) { this.cities = countries; } @Override public DataAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) { View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.card_row, viewGroup, false); return new ViewHolder(view); } @Override public void onBindViewHolder(DataAdapter.ViewHolder viewHolder, int i) { viewHolder.tv_country.setText(cities.get(i)); } @Override public int getItemCount() { return cities.size(); } public class ViewHolder extends RecyclerView.ViewHolder{ private TextView tv_country; public ViewHolder(View view) { super(view); tv_country = (TextView)view.findViewById(R.id.tv_country); } } }
Step 6 − Add the following code to Manifests/AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.app.sample"> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
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 the 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 −
Click here to download the project code.
- Related Questions & Answers
- How ListView's recycling mechanism works on Android using Kotlin?
- How to dynamically update a ListView on Android
- How to create focusable editText inside ListView on Android?
- How to dynamically update a ListView on Android Kotlin?
- How to add custom adapter for my listView on Android?
- How to change the background color of ListView items on Android?
- How to implement a long click listener on a Android listview?
- How to create Focusable EditText inside ListView on Android using Kotlin?
- How to binarySearch in android listview?
- How to sort Listview in Android?
- How to give on click listener for footer view in android listview?
- How to change the background color of ListView items on Android Kotlin?
- How does Constraint Layout works in android?
- How to make a ListView in android?
- How to add footer in Android ListView?