How to display Contacts in alphabetic order in Listview [closed]

Answer 1

use this code to retrieve the contacts

ArrayList> contactData=new ArrayList>();
ContentResolver cr = getContentResolver();
     Cursor cursor = getContentResolver().query(ContactsContract.Contacts.CONTENT_URI,null, null, null, null);
     while (cursor.moveToNext()) {
         try{
         String contactId = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID)); 
         String name=cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
         String hasPhone = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER)); 
         if (Integer.parseInt(cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER))) > 0) {
             Cursor phones = getContentResolver().query( ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, ContactsContract.CommonDataKinds.Phone.CONTACT_ID +" = "+ contactId, null, null);
             while (phones.moveToNext()) { 
                 String phoneNumber = phones.getString(phones.getColumnIndex( ContactsContract.CommonDataKinds.Phone.NUMBER));
                 HashMap map=new HashMap();
                 map.put("name", name);
                 map.put("number", phoneNumber);
                 contactData.add(map);
             } 
             phones.close(); 
         }
     }catch(Exception e){}
     }

Now the contact details are stored in the contactData ArrayList. Now sort this arrayList like bellow

Collections.sort(contactData, new Comparator(){
                @Override
                public int compare(Object o1, Object o2) {
                    HashMap map1=(HashMap)o1;
                    HashMap map2=(HashMap)o2;
                    String s1=(String)map1.get("name");
                    String s2=(String)map2.get("name");
                    return s1.compareTo(s2);
                }
            });

Now the contact details are stored in the sorting order in the contactData ArrayList.