Android spinner (drop down list) example

In Android, the you can use “android.widget.Spinner” class to render a dropdown box selection list.

Note
Spinner is a widget similar to a drop-down list for selecting items.
In this tutorial, we show you how to do the following tasks :

Render a Spinner in XML, and load the selection items via XML file also.
Render another Spinner in XML, and load the selection items via code dynamically.
Attach a listener on Spinner, fire when user select a value in Spinner.
Render and attach a listener on a normal button, fire when user click on it, and it will display selected value of Spinner.
P.S This project is developed in Eclipse 3.7, and tested with Android 2.3.3.

1. List of Items in Spinner

Open “res/values/strings.xml” file, defined the list of items that will display in Spinner (dropdown list).

File : res/values/strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">MyAndroidApp</string>
    <string name="country_prompt">Choose a country</string>

    <string-array name="country_arrays">
        <item>Malaysia</item>
        <item>United States</item>
        <item>Indonesia</item>
        <item>France</item>
        <item>Italy</item>
        <item>Singapore</item>
        <item>New Zealand</item>
        <item>India</item>
    </string-array>

</resources>

2. Spinner (DropDown List)

Open “res/layout/main.xml” file, add two spinner components and a button.

In “spinner1″, the “android:entries” represents the selection items in spinner.
In “spinner2″, the selection items will be defined in code later.
File : res/layout/main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Spinner
        android:id="@+id/spinner1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:entries="@array/country_arrays"
        android:prompt="@string/country_prompt" />

    <Spinner
        android:id="@+id/spinner2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btnSubmit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Submit" />

</LinearLayout>

3. Code Code

Read the code and also code’s comment, it should be self-explanatory.

File : MyAndroidAppActivity.java

package com.mkyong.android;

import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.Toast;

public class MyAndroidAppActivity extends Activity {

private Spinner spinner1, spinner2;
private Button btnSubmit;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    addItemsOnSpinner2();
    addListenerOnButton();
    addListenerOnSpinnerItemSelection();
}

// add items into spinner dynamically
public void addItemsOnSpinner2() {

    spinner2 = (Spinner) findViewById(R.id.spinner2);
    List<String> list = new ArrayList<String>();
    list.add("list 1");
    list.add("list 2");
    list.add("list 3");
    ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
        android.R.layout.simple_spinner_item, list);
    dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner2.setAdapter(dataAdapter);
}

public void addListenerOnSpinnerItemSelection() {
    spinner1 = (Spinner) findViewById(R.id.spinner1);
    spinner1.setOnItemSelectedListener(new CustomOnItemSelectedListener());
}

// get the selected dropdown list value
public void addListenerOnButton() {

    spinner1 = (Spinner) findViewById(R.id.spinner1);
    spinner2 = (Spinner) findViewById(R.id.spinner2);
    btnSubmit = (Button) findViewById(R.id.btnSubmit);

    btnSubmit.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {

        Toast.makeText(MyAndroidAppActivity.this,
        "OnClickListener : " +
                "\nSpinner 1 : "+ String.valueOf(spinner1.getSelectedItem()) +
                "\nSpinner 2 : "+ String.valueOf(spinner2.getSelectedItem()),
            Toast.LENGTH_SHORT).show();
    }

    });
}
}
File : CustomOnItemSelectedListener.java

package com.mkyong.android;

import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Toast;

public class CustomOnItemSelectedListener implements OnItemSelectedListener {

public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
    Toast.makeText(parent.getContext(),
        "OnItemSelectedListener : " + parent.getItemAtPosition(pos).toString(),
        Toast.LENGTH_SHORT).show();
}

@Override
public void onNothingSelected(AdapterView<?> arg0) {
    // TODO Auto-generated method stub
}

}