Merhaba arkadaşlar bu konumuzda android de time zone uygulaması yapımını öğreneceğiz. Bu uygulamamızda listeden seçeceğimiz bir ülkenin saatini, bulunduğumuz yere göre saat farkını ve ekrana yazdıracağız.

Aşağıda yer alan kodları mainActivity’de onCreate metotun’dan önce ekliyoruz.

private Spinner spinnerAvailableID;
private Calendar current;
private TextView textTimeZone, txtCurrentTime, txtTimeZoneTime;
private long miliSeconds;
private ArrayAdapter<String> idAdapter;
private SimpleDateFormat sdf;
private Date resultdate;

Aşağıda getGMTtime metodumuz yer almakta bu metodu onCreate metodun dan hemen sonra ekliyoruz.

private void getGMTTime() {
current = Calendar.getInstance();
txtCurrentTime.setText("" + current.getTime());
 
miliSeconds = current.getTimeInMillis();
 
TimeZone tzCurrent = current.getTimeZone();
int offset = tzCurrent.getRawOffset();
if (tzCurrent.inDaylightTime(new Date())) {
offset = offset + tzCurrent.getDSTSavings();
}
 
miliSeconds = miliSeconds - offset;
 
resultdate = new Date(miliSeconds);
System.out.println(sdf.format(resultdate));
}

Aşağıda yer alan kodları onCreate Metodu içerisine ekliyoruz.

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

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

    String[] idArray = TimeZone.getAvailableIDs();

    sdf = new SimpleDateFormat("EEEE, dd MMMM yyyy HH:mm:ss");

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

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

    getGMTTime();

    spinnerAvailableID
        .setOnItemSelectedListener(new OnItemSelectedListener() {

          @Override
          public void onItemSelected(AdapterView<?> parent,
              View view, int position, long id) {
            getGMTTime();
            String selectedId = (String) (parent
                .getItemAtPosition(position));

            TimeZone timezone = TimeZone.getTimeZone(selectedId);
            String TimeZoneName = timezone.getDisplayName();

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

            int hrs = TimeZoneOffset / 60;
            int mins = TimeZoneOffset % 60;

            miliSeconds = miliSeconds + timezone.getRawOffset();

            resultdate = new Date(miliSeconds);
            System.out.println(sdf.format(resultdate));

            textTimeZone.setText(TimeZoneName + " : GMT " + hrs + "."
                + mins);
            txtTimeZoneTime.setText("" + sdf.format(resultdate));
            miliSeconds = 0;
          }

          @Override
          public void onNothingSelected(AdapterView<?> arg0) {

          }
        });

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center|top"
    android:orientation="vertical"
    android:padding="5dp" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/txtGMTTime"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/current" />

        <TextView
            android:id="@+id/txtCurrentTime"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            tools:context=".MainActivity" />
    </LinearLayout>

    <Spinner
        android:id="@+id/availableID"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/timezone"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:id="@+id/txtTimeZoneTime"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </LinearLayout>

</LinearLayout>