Simple ListView

Now let’s see about ListView in android.

In this project, we are going to show a list of android versions in a ListView.

for that create a new project named List_View (you can change the name as your wish :p ).

Now enter the following data in your activity_main.xml file

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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="com.a4akhilsudha.list_view.MainActivity">

    <ListView
        android:id="@+id/listView"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_margin="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

Now create a string array in your string.xml file. In here we are creating a list of android versions.

<resources>
    <string name="app_name">List_View</string>

    <string-array name="android_versions">
    <item>Apple pie</item>
    <item>Banana bread</item>
    <item>Cupcake</item>
    <item>Donut</item>
    <item>Eclair</item>
    <item>Froyo</item>
    <item>Gingerbread</item>
    <item>Honeycomb</item>
    <item>Ice cream sandwich</item>
    <item>Jellybean</item>
    <item>Kitkat</item>
    <item>Lollipop</item>
    <item>Marshmallow</item>
    <item>Nougat</item>
    <item>Oreo</item>
    </string-array>
</resources>

Now open your MainActivity.kt file and enter the following data.

package com.a4akhilsudha.list_view

import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.widget.ArrayAdapter
import android.widget.ListView
import android.widget.Toast

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        /*find the id of the ListView*/
        val listView = findViewById(R.id.listView) as ListView

        /*Set an adapter for the list view having the string array*/
        listView.adapter = ArrayAdapter(this, R.layout.support_simple_spinner_dropdown_item, resources.getStringArray(R.array.android_versions))

        /*set click listener for listView*/
        listView.setOnItemClickListener { parent, view, position, id ->

         Toast.makeText(this@MainActivity, "You have Clicked " + parent.getItemAtPosition(position), Toast.LENGTH_SHORT).show()
        }
    }
}

Now run (Shift + f10) the program on a real device or in a  virtual device.

Congrats …. 🙂 You just created an android app which displays a list of android versions.

Output :