Get Installed Time Zone

The java.util.TimeZone class represents a time zone, primarily used for configuring a Calendar or SimpleDateFormat instance.

The method getAvailableIDs() returns the system's installed time zone IDs. Any of these IDs can be passed to getTimeZone() to lookup the corresponding time zone instance.

package com.exercise.AndroidTimeZone;



import java.util.TimeZone;



import android.app.Activity;

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.TextView;



public class AndroidTimeZoneActivity extends Activity {

	

	Spinner spinnerAvailableID;

	TextView textTimeZone;

	

	ArrayAdapter<String> idAdapter;

	

   /** Called when the activity is first created. */

   @Override

   public void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.main);

      

       spinnerAvailableID = (Spinner)findViewById(R.id.availableID);

       textTimeZone = (TextView)findViewById(R.id.timezone);

      

       String[] idArray = TimeZone.getAvailableIDs();

       idAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, idArray);

       idAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

       spinnerAvailableID.setAdapter(idAdapter);

      

       spinnerAvailableID.setOnItemSelectedListener(new OnItemSelectedListener(){



			@Override

			public void onItemSelected(AdapterView<?> parent, View view,

					int position, long id) {

				// TODO Auto-generated method stub

				String selectedId = (String)(parent.getItemAtPosition(position));

				TimeZone timezone = TimeZone.getTimeZone(selectedId);		

				

				String TimeZoneName = timezone.getDisplayName();

				int TimeZoneOffset = timezone.getRawOffset()/(60 * 60 * 1000);

				

				textTimeZone.setText(TimeZoneName + " : " +String.valueOf(TimeZoneOffset));

			}



			@Override

			public void onNothingSelected(AdapterView<?> arg0) {

				// TODO Auto-generated method stub

				

			}});

   }

}

<?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"

   >

<TextView 

   android:layout_width="fill_parent"

   android:layout_height="wrap_content"

   android:text="@string/hello"

   />

<Spinner

   android:id="@+id/availableID"

   android:layout_width="fill_parent"

   android:layout_height="wrap_content"

	/>

<TextView 

   android:id="@+id/timezone"

   android:layout_width="fill_parent"

   android:layout_height="wrap_content"

   />

</LinearLayout>

Related Post:
- Get time zone where currently running, using TimeZone.getDefault()