How To read Contact ID and Name from android

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
     
        Cursor c=getContacts();
        c.moveToFirst();
   
    while(c.isAfterLast()==false)
    {
    String data="::";
    for(int i=0;i<c.getColumnCount();i++)
    {
    data=data.concat(c.getString(c.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME))+":"+c.getString(c.getColumnIndex(ContactsContract.Contacts._ID)));
    }
    Toast.makeText(getApplicationContext(), data,Toast.LENGTH_LONG).show();
    c.moveToNext();
    }
     
    }
 
    private Cursor getContacts()
    {

        Uri uri = ContactsContract.Contacts.CONTENT_URI;
        String[] projection = new String[] {
                ContactsContract.Contacts._ID,
                ContactsContract.Contacts.DISPLAY_NAME,    
        };

        String selection = ContactsContract.Contacts.HAS_PHONE_NUMBER;
        String[] selectionArgs = null;
        String sortOrder = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC";

        return managedQuery(uri, projection, selection, selectionArgs, sortOrder);
    }