How to sort HashMap in Android?

Question

How to sort HashMap<String,ArrrayList<String>>?

I am fetching contact name from phone contacts like:

"String name = cur.getString(cur.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));"

And stored it into one HashMap<String,ArrayList<String>>. But all contacts I am getting in unsorted order.

May I know how to sort those contacts in alphabetical order so that I can display list view in sorted order?

possible duplicate of [How to sort a Map on the values in Java?](http://stackoverflow.com/questions/109383/how-to-sort-a-mapkey-value-on-the-values-in-java) — Joe, Jan 22 '15 at 10:49

score 1 · Answer 1 · answered Jan 22 '15 at 06:40

You can retrieve your data from the database already sorted. Just use

String orderBy =  ContactsContract.Contacts.DISPLAY_NAME + " DESC";

in your query. After that, usually when you need to use HashMap an have also sorted data, then you use HashMap + ArrayList. In HashMap you keep normal key,value pairs, in ArrayList you keep sorted values (in case if you have already sorted data, you add it to ArrayList while reading, you don't need to sort again).

If you need to sort ArrayList which is value in your HashMap, you can use:

Collections.sort(yourArrayList);

score 1 · Answer 2 · answered Jan 22 '15 at 06:44

1

Use below class and pass List of data to the it. It will give you new sorted list.

public class CompareApp implements Comparator<AppDetails> {

private List<AppDetails> apps = new ArrayList<AppDetails>();

Context context;

public CompareApp(String str,List<AppDetails> apps, Context context) {
    this.apps = apps;
    this.context = context;

    Collections.sort(this.apps, this);
}

@Override
public int compare(AppDetails lhs, AppDetails rhs) {
    // TODO Auto-generated method stub
    return lhs.label.toUpperCase().compareTo(rhs.label.toUpperCase());
}

}

answered Jan 22 '15 at 06:44

Pratik

452
4
17

AppDetails is a generic class – Pratik Jan 22 '15 at 06:54
public class AppDetails { public String label; public String packageName; public Drawable icon; } – Pratik Jan 22 '15 at 06:56

score 0 · Accepted Answer · answered Jan 22 '15 at 06:52

0

I used following code to get Contacts in Ascending Order of String names as follows:

public void getAllContacts(ContentResolver cr) {


        Cursor phones = cr.query(
                ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null,
                null, Phone.DISPLAY_NAME + " ASC");

        while (phones.moveToNext()) {
            String name = phones
                    .getString(phones
                            .getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
            String phoneNumber = phones
                    .getString(phones
                            .getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
            name1.add(name);
            phno1.add(phoneNumber);
        } 


        phones.close();
    }

Code for reference

Hope this is what you need.

answered Jan 22 '15 at 06:52

virendrao

1,763
2
22
42

one more question .can you tell me how to add search option in my custom adapter for listview – User_B Jan 22 '15 at 06:58
@User_B You can add a EditText component as HeaderView in ListView of yours. – virendrao Jan 22 '15 at 07:04
do you have some snippet – User_B Jan 22 '15 at 07:05
Just put Edit Text above listview component else – virendrao Jan 22 '15 at 07:11
@User_B you are looking for this i guess http://www.androidbegin.com/tutorial/android-search-listview-using-filter/ – virendrao Jan 22 '15 at 07:14
yes i rhave already refferd this link but result is like when i type 'a' ,all the names which conatins 'a' for eg. 'manish' is also displayed. how to dispay records only starting with whatever i typed in edit text – User_B Jan 22 '15 at 07:29
you need to implement something like trie data structure then. – virendrao Jan 22 '15 at 08:56

How to sort HashMap in Android?

3 Answers3