Apps Create app Contact simple

[HackerNam]

Target
Helps you build an application that can read the list of contacts, add, delete contacts.

Step 1: Construction data processing layer contacts
Create a class called ContentHelper to handle contacts. This class will have the task of returning a cursor containing all contacts.


Step 2: Get a list of all contacts

public static Cursor getContactCursor(ContentResolver contactHelper, String startsWith) {

    String[] projection = { ContactsContract.CommonDataKinds.Phone._ID, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER };
    Cursor cur = null;
   
    try {
        if (startsWith != null && !startsWith.equals("")) {
            cur = contactHelper.query (ContactsContract.CommonDataKinds.Phone.CONTENT_URI, projection, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " like \"" + startsWith + "%\"", null, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " ASC");
        } else {
            cur = contactHelper.query (ContactsContract.CommonDataKinds.Phone.CONTENT_URI, projection, null, null, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " ASC");
        }
        cur.moveToFirst();
    }
    catch (Exception e) {
        e.printStackTrace();
    }
    return cur;
}

To learn more about the ingredients you should learn more in the following link:
https://developer.android.com/reference/android/content/ContentResolver.html
https://developer.android.com/guide/topics/providers/content-provider-basics.html
https://developer.android.com/guide/topics/providers/contacts-provider.html

Step 3: Add contacts

public static boolean insertContact(ContentResolver contactAdder, String firstName, String mobileNumber) {
    ArrayList<ContentProviderOperation> ops = new ArrayList<ContentProviderOperation>();
    ops.add(ContentProviderOperation.newInsert(ContactsContract.RawContacts.CONTENT_URI).withValue(ContactsContract.RawContacts.ACCOUNT_TYPE, null).withValue(ContactsContract.RawContacts.ACCOUNT_NAME, null).build());
   
    ops.add(ContentProviderOperation.newInsert(ContactsContract.Data.CONTENT_URI).withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, 0).withValue(ContactsContract.Data.MIMETYPE,ContactsContract.CommonDataKinds.StructuredName.CONTENT_ITEM_TYPE).withValue(ContactsContract.CommonDataKinds.StructuredName.GIVEN_NAME,firstName).build());
   
    ops.add(ContentProviderOperation.newInsert(ContactsContract.Data.CONTENT_URI).withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, 0).withValue(ContactsContract.Data.MIMETYPE,ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE).withValue(ContactsContract.CommonDataKinds.Phone.NUMBER,mobileNumber).withValue(ContactsContract.CommonDataKinds.Phone.TYPE,Phone.TYPE_MOBILE).build());

    try {
        contactAdder.applyBatch(ContactsContract.AUTHORITY, ops);
    } catch (Exception e) {
    return false;
    }
return true;
}

Step 4: Delete contacts

public static void deleteContact(ContentResolver contactHelper, String number) {

    ArrayList<ContentProviderOperation> ops = new ArrayList<ContentProviderOperation>();
    String[] args = new String[] { String.valueOf(getContactID(contactHelper, number)) };

    ops.add(ContentProviderOperation.newDelete(RawContacts.CONTENT_URI).withSelection(RawContacts.CONTACT_ID + "=?", args).build());

    try {
        contactHelper.applyBatch(ContactsContract.AUTHORITY, ops);
    } catch (RemoteException e) {
        e.printStackTrace();
    } catch (OperationApplicationException e) {
        e.printStackTrace();
    }
}

This class is used to retrieve the ID of the contacts that you want to retrieve

private static long getContactID(ContentResolver contactHelper,String number) {
    Uri contactUri = Uri.withAppendedPath(PhoneLookup.CONTENT_FILTER_URI, Uri.encode(number));
    String[] projection = { PhoneLookup._ID };
    Cursor cursor = null;
   
    try {
        cursor = contactHelper.query(contactUri, projection, null, null,null);

        if (cursor.moveToFirst()) {
            int personID = cursor.getColumnIndex(PhoneLookup._ID);
            return cursor.getLong(personID);
        }
        return -1;

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (cursor != null) {
            cursor.close();
            cursor = null;
        }
    }
return

Full source code:
https://drive.google.com/file/d/0B7V9D29Tek7yeWtNZ2N4cVM0bDA/view?usp=sharing