Spinner in Android with Example

Android Spinner is a view similar to the dropdown list which is used to select one option from the list of options. It provides an easy way to select one item from the list of items and it shows a dropdown list of all values when we click on it. The default value of the android spinner will be the currently selected value and by using Adapter we can easily bind the items to the spinner objects. Generally, we populate our Spinner control with a list of items by using an ArrayAdapter in our Kotlin/Java file.

Important Attributes for Spinner Widget

XML attributes	Description
android:id	Used to specify the id of the view.
android:textAlignment	Used to the text alignment in the dropdown list.
android:background	Used to set the background of the view.
android:padding	Used to set the padding of the view.
android:visibility	Used to set the visibility of the view.
android:gravity	Used to specify the gravity of the view like center, top, bottom, etc

Steps to Implement Spinner

Here is an example of an Android application that displays the list of courses of GFG. Use ArrayAdapter to store the courses list. Create a single MainActivity that contains the spinner and on clicking any item of spinner Toast with that course name will be shown.

Step 1: Create a new Project

To create a new Project in Android Studio please refer to How to Create/Start a New Project in Android Studio using Kotlin.

We are going to use both Java and Kotlin.

Step 2: Working with the activity_main.xml

Now open activity_main.xml and insert the below code in it.

activity_main.xml:

XML

<?xml version="1.0" encoding="utf-8"?>
<!--Constraint layout which contain Spinner widget-->
<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"
    android:background="@color/white"
    tools:context=".MainActivity">

    <!--Spinner widget-->
    <Spinner
        android:id="@+id/spinner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingHorizontal="16dp"
        android:paddingVertical="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

Step 3: Working with the MainActivity.kt

There is one activity and hence one Java/Kotlin file for the MainActivity file. Java/Kotlin file for Main Activity, in which Array Adapter is used to bind data to the spinner. We will fill data in the array of strings and bind that data to the spinner. Here is the code:

MainActivity File:

Java

package org.geeksforgeeks.demo;

import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

    // Create array of Strings and store the names of courses
    private String[] courses = {
            "C", "Data structures",
            "Interview prep", "Algorithms",
            "DSA with java", "OS"
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Take the instance of Spinner and apply OnItemSelectedListener on it
        Spinner spin = findViewById(R.id.spinner);
        spin.setOnItemSelectedListener(this);

        // Create the instance of ArrayAdapter having the list of courses
        ArrayAdapter<String> ad = new ArrayAdapter<>(
                this,
                android.R.layout.simple_spinner_item,
                courses
        );

        // Set simple layout resource file for each item of spinner
        ad.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        // Set the ArrayAdapter (ad) data on the Spinner which binds data to spinner
        spin.setAdapter(ad);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        // Make toast of the name of the course which is selected in the spinner
        Toast.makeText(getApplicationContext(), courses[position], Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
        // No action needed when no selection is made
    }
}

Kotlin

package org.geeksforgeeks.demo

import android.os.Bundle
import android.view.View
import android.widget.AdapterView
import android.widget.AdapterView.OnItemSelectedListener
import android.widget.ArrayAdapter
import android.widget.Spinner
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity(), OnItemSelectedListener {
    // create array of Strings
    // and store name of courses
    private var courses = arrayOf(
        "C", "Data structures",
        "Interview prep", "Algorithms",
        "DSA with java", "OS"
    )

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

        // Take the instance of Spinner and
        // apply OnItemSelectedListener on it which
        // tells which item of spinner is clicked
        val spin = findViewById<Spinner>(R.id.spinner)
        spin.onItemSelectedListener = this

        // Create the instance of ArrayAdapter
        // having the list of courses
        val ad: ArrayAdapter<*> = ArrayAdapter<Any?>(this,
            android.R.layout.simple_spinner_item, courses
        )

        // set simple layout resource file
        // for each item of spinner
        ad.setDropDownViewResource(
            android.R.layout.simple_spinner_dropdown_item
        )

        // Set the ArrayAdapter (ad) data on the
        // Spinner which binds data to spinner
        spin.adapter = ad
    }

    override fun onItemSelected(parent: AdapterView<*>?, view: View,
            position: Int,id: Long) 
    {
        // make toast of name of course
        // which is selected in spinner
        Toast.makeText(applicationContext, courses[position], Toast.LENGTH_SHORT).show()
    }

    override fun onNothingSelected(parent: AdapterView<*>?) {}
}