A spinner widget enables a user to select an item from a list of options. In the normal state it shows the currently selected item. Clicking on the spinner widget shows a dropdown menu with all available items. The user can choose a new one from the list. The Spinner
class is used to create a spinner widget.
The Spinner widget can be populated in the XML file. Or it can be programmatically filled. In the latter case we need an Adapter class to populate the Spinner
widget. An adapter is a bridge between a Spinner
and its data.
Spinner I
In the first example we have a Spinner
widget whose items are defined in an XML file.
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.shishirkant.finish" android:versionCode="1" android:versionName="1.0"> <application android:label="@string/app_name" android:icon="@drawable/ic_launcher"> <activity android:name="MainActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
This is the manifest file for the program.
main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <Spinner android:id="@+id/spn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:entries="@array/dlangs" android:layout_marginTop="10dip" android:prompt="@string/spn_title" /> <TextView android:id="@+id/tvId" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginTop="10dip" /> </LinearLayout>
In the main.xml
layout file, we have a Spinner
and a TextView
. The android:entries="@array/dlangs"
attribute defines a XML resource that provides an array of strings. The strings are written in the strings.xml
file.
strings.xml
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="app_name">Spinner</string> <string name="spn_title">Choose a language</string> <string-array name="dlangs"> <item>Python</item> <item>PHP</item> <item>Perl</item> <item>Tcl</item> <item>Ruby</item> </string-array> </resources>
In the strings.xml
file we have the elements of the string array. These are displayed when we click on the Spinner
widget.
MainActivity.java
package com.shishirkant.spinner; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.TextView; import android.widget.Spinner; import android.widget.AdapterView; import android.widget.AdapterView.OnItemSelectedListener; public class MainActivity extends Activity implements OnItemSelectedListener { private TextView tv; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); tv = (TextView) findViewById(R.id.tvId); Spinner spn = (Spinner) findViewById(R.id.spn); spn.setOnItemSelectedListener(this); } @Override public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) { String item = parent.getItemAtPosition(pos).toString(); tv.setText(item); } @Override public void onNothingSelected(AdapterView<?> arg0) { tv.setText(""); } }
The selected item from the Spinner
widget is displayed in the TextView
widget.
public class MainActivity extends Activity implements OnItemSelectedListener
The MainActivity class implements the OnItemSelectedListener
. The class must now implement two methods. The onItemSelected()
and onNothingSelected()
methods.
Spinner spn = (Spinner) findViewById(R.id.spn); spn.setOnItemSelectedListener(this);
These two lines get the reference to the Spinner
widget and set the OnItemSelectedListener
for it.
@Override public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) { String item = parent.getItemAtPosition(pos).toString(); tv.setText(item); }
In the onItemSelected()
method we get the currently selected Spinner
item with the getItemAtPosition()
. The item is transformed to a string and set to the TextView
.

Spinner II
In the second spinner example, we will define our list of spinner elements programmatically. For this we will use the ArrayAdapter
in conjunction with the ArrayList
.
An Adapter design pattern is used by Android platform to work with the Spinner
widget. The ArrayAdapter
is an intermediary between the data source and the data view. In this case the data source is the ArrayList
and the view is the Spinner
widget. Using an adapter we are decoupling our code.
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.shishirkant.toast" android:versionCode="1" android:versionName="1.0"> <application android:label="@string/app_name" android:icon="@drawable/ic_launcher"> <activity android:name="MainActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
This is the manifest file.
main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <Spinner android:id="@+id/spnId" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="10dip" android:prompt="@string/spn_title" /> <TextView android:id="@+id/tvId" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginTop="10dip" /> </LinearLayout>
In the main.xml
file we have two widgets. The Spinner
and the TextView
widget. This time we do not define the array data entries for the Spinner
.
strings.xml
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="app_name">Spinner2</string> <string name="spn_title">Choose a language</string> </resources>
This is the strings.xml
resource file.
MainActivity.java
package com.shishirkant.spinner2; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Spinner; import android.widget.ArrayAdapter; import android.widget.TextView; import android.widget.AdapterView; import android.widget.AdapterView.OnItemSelectedListener; public class MainActivity extends Activity implements OnItemSelectedListener { private TextView tv; private Spinner spn; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); setup(); } public void setup() { tv = (TextView) findViewById(R.id.tvId); spn = (Spinner) findViewById(R.id.spnId); fillSpinner(spn); spn.setOnItemSelectedListener(this); } public void fillSpinner(Spinner spn) { List<String> lst = new ArrayList<String>(); lst.add("Python"); lst.add("PHP"); lst.add("Perl"); lst.add("Tcl"); lst.add("Ruby"); ArrayAdapter<String> da = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, lst); da.setDropDownViewResource(android.R.layout.simple_spinner_item); spn.setAdapter(da); } @Override public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) { String item = parent.getItemAtPosition(pos).toString(); tv.setText(item); } @Override public void onNothingSelected(AdapterView<?> arg0) { tv.setText(""); } }
In the MainActivity.java
source file we fill the Spinner widget with data and implement the OnItemSelectedListener
for the widget.
spn = (Spinner) findViewById(R.id.spnId); fillSpinner(spn);
We get the reference to the Spinner
widget and call the fillSpinner() method to populate it with data.
List<String> lst = new ArrayList<String>(); lst.add("Python"); lst.add("PHP"); lst.add("Perl"); lst.add("Tcl"); lst.add("Ruby");
An ArrayList
is created and filled with strings.
ArrayAdapter<String> da = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, lst);
The instance of the ArrayAdapter
is created. It takes the ArrayList as a parameter.
da.setDropDownViewResource(android.R.layout.simple_spinner_item);
This line determines the look of the dropdown menu of the Spinner
widget. This one is a dropdown without radio buttons. A spinner with the android.R.layout.simple_spinner_dropdown_item
defined has radio buttons in its rows.
spn.setAdapter(da);
The adapter is set for the Spinner widget.
