- Contact Class: Part 1 6:05
- Create a Contact Class 1 objective
- Contact Class: Part 2 4:04
- Write a Method 1 objective
- Phone Number Class 6:15
- Write a to_s Method 1 objective
- Address Class: Part 1 5:00
- Address Class: Part 2 3:44
- Initializing and Calling Methods 2 objectives
- Address Book Class 4:25
- Instance variable instantiation 2 objectives
Preview
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Address Book Class
4:25With all of our supporting classes set up, we can define an `AddressBook` class to hold our program.
Okay, so we've got our contact, phone
number, and address classes all set up.
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Now our contact when we
initialize it has addresses and
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phone numbers, but remember we're
building an address book here.
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So an address book is going
to have many contacts.
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Now let's go ahead and represent
an address book with another class.
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So once again, do New File, and
we'll call this address_book.rb.
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And this will be an address book class.
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Now just like we did with our contacts,
having addresses and
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phone numbers,
when we initialize an address book class,
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we'll have our contact be an empty array.
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And that's gonna be an instance variable.
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So any method in address book
is going to have access to it.
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Now, so that we don't have
to use the at sign each time
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we want to refer to the contact,
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we'll say we have an attribute reader for
contacts.
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And let's go ahead and
create a method to print our contact list,
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and then we can just iterate
through the contacts.
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And we'll print out our contact, and we
can use the last name, first name format.
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So now that we have
the address book class set up,
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we can instantiate one, and then let's
go ahead and add a contact to it.
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And actually I think I can just
grab this from our contact file.
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I'm gonna copy that, And paste it,
and then I can take it out of here,
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So that it's not cluttering up
the output like we had before.
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So now we can say address_book.contacts,
and
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we will add this contact
that we just created.
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And now we can print
the contact list as well.
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And let's just say Contact List.
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Okay, now let's run address_book.rb,
and this is not gonna work correctly.
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Can you guess why?
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And here we get the message
uninitialized constant Contact.
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And the reason is we haven't told Ruby
that we're gonna be using that class.
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So we have to do it the same way that we
did in the contact class where we require
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phone numbers and addresses.
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We have to tell our address book,
To require contacts.
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So let me clear my screen here and
print this again.
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And hey, here we go.
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Our contact list now has my name on it.
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And go ahead and just add another contact.
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Just to make sure it all prints correctly.
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Okay.
And one more time.
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All right.
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So far,
our contact list is looking pretty good.
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