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With all of our supporting classes set up, we can define an `AddressBook` class to hold our program.
Code Samples
require "./contact"
class AddressBook
attr_reader :contacts
def initialize
@contacts = []
end
def print_contact_list
puts "Contact List"
contacts.each do |contact|
puts contact.to_s('last_first')
end
end
end
address_book = AddressBook.new
jason = Contact.new
jason.first_name = "Jason"
jason.last_name = "Seifer"
jason.add_phone_number("Home", "123-456-7890")
jason.add_phone_number("Work", "456-789-0123")
jason.add_address("Home", "123 Main St.", "", "Portland", "OR", "12345")
nick = Contact.new
nick.first_name = "Nick"
nick.last_name = "Pettit"
nick.add_phone_number("Home", "222-222-2222")
nick.add_address("Home", "222 Two Lane", "", "Portland", "OR", "12345")
address_book.contacts.push(jason)
address_book.contacts.push(nick)
address_book.print_contact_list
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Okay, so we've got our contact, phone
number, and address classes all set up.
0:00
Now our contact when we
initialize it has addresses and
0:05
phone numbers, but remember we're
building an address book here.
0:09
So an address book is going
to have many contacts.
0:14
Now let's go ahead and represent
an address book with another class.
0:18
So once again, do New File, and
we'll call this address_book.rb.
0:23
And this will be an address book class.
0:34
Now just like we did with our contacts,
having addresses and
0:38
phone numbers,
when we initialize an address book class,
0:42
we'll have our contact be an empty array.
0:50
And that's gonna be an instance variable.
0:53
So any method in address book
is going to have access to it.
0:56
Now, so that we don't have
to use the at sign each time
1:02
we want to refer to the contact,
1:06
we'll say we have an attribute reader for
contacts.
1:09
And let's go ahead and
create a method to print our contact list,
1:14
and then we can just iterate
through the contacts.
1:20
And we'll print out our contact, and we
can use the last name, first name format.
1:32
So now that we have
the address book class set up,
1:42
we can instantiate one, and then let's
go ahead and add a contact to it.
1:48
And actually I think I can just
grab this from our contact file.
1:55
I'm gonna copy that, And paste it,
and then I can take it out of here,
2:02
So that it's not cluttering up
the output like we had before.
2:13
So now we can say address_book.contacts,
and
2:20
we will add this contact
that we just created.
2:24
And now we can print
the contact list as well.
2:33
And let's just say Contact List.
2:39
Okay, now let's run address_book.rb,
and this is not gonna work correctly.
2:44
Can you guess why?
2:52
And here we get the message
uninitialized constant Contact.
2:54
And the reason is we haven't told Ruby
that we're gonna be using that class.
3:00
So we have to do it the same way that we
did in the contact class where we require
3:06
phone numbers and addresses.
3:10
We have to tell our address book,
To require contacts.
3:12
So let me clear my screen here and
print this again.
3:21
And hey, here we go.
3:25
Our contact list now has my name on it.
3:27
And go ahead and just add another contact.
3:33
Just to make sure it all prints correctly.
3:42
Okay.
And one more time.
4:18
All right.
4:21
So far,
our contact list is looking pretty good.
4:22
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