android添加群组源码

private void addContactToGroup(int contactId,int groupId) {
                //judge whether the contact has been in the group
                boolean b1 = ifExistContactInGroup(contactId, groupId);
                if (b1) {
                        //the contact has been in the group
                        return;
                } else {
                        ContentValues values = new ContentValues();     
                        values.put(ContactsContract.CommonDataKinds.GroupMembership.RAW_CONTACT_ID,contactId);
                        values.put(ContactsContract.CommonDataKinds.GroupMembership.GROUP_ROW_ID,groupId);
                        values.put(ContactsContract.CommonDataKinds.GroupMembership.MIMETYPE,ContactsContract.CommonDataKinds.GroupMembership.CONTENT_ITEM_TYPE);
                        getContentResolver().insert(ContactsContract.Data.CONTENT_URI, values); 
                }
        }
        
        private boolean ifExistContactInGroup(int contactId, int groupId) {
                String where = Data.MIMETYPE + " = '" + ContactsContract.CommonDataKinds.GroupMembership.CONTENT_ITEM_TYPE
                                + "' AND " + Data.DATA1 + " = '" + groupId
                                + "' AND " + Data.RAW_CONTACT_ID + " = '" + contactId + "'";
                Cursor markCursor = getContentResolver().query(Data.CONTENT_URI, new String[]{Data.DISPLAY_NAME}, where, null, null);
                if (markCursor.moveToFirst()) {
                        return true;
                }else {
                        return false;
                }
        }