Visual Basic Tutorial - 115 - Car Part 10 Adding The Cars To A List Video Lecture | Mastering Visual Basic - Web Development

hello YouTube sam here from youtube.com
slash on live gamer for the new Boston
and in this tutorial we're gonna be
working more on the truck class and then
we're gonna start building the interface
for our program and adding more to it so
let's go ahead and add one more thing
that we're going to be that we're gonna
need for our truck class so we'll just
add a function that gives the
information about the truck so let's
come up here to our car class and let's
find the two string function that has
been overridden so you can see here
we've got name color number of doors and
speed so we'll go ahead and copy that
because we're gonna use that as the base
for our get information now you may be
thinking we could just use the two
string and it asks us to that well we're
gonna be adding stuff in between those
values so that won't be very practical
so we'll type public function get truck
info as string so it's going to be
returning a string so we're just gonna
return the name the color the number of
doors and in between here let's go ahead
and add the cab size so and then we will
add truck cab length
so then we'll add the bed length so
let's type bed length and then we will
add the length value so truck bed length
and now we will add just the number of
doors so we're gonna need a new line in
between each one of these so environment
dot new line and then we'll add this
string right here and then one more new
line right here so environment dot new
line ok so now that we have everything
we need for the truck class let's go
ahead and minimize that and you can see
that I've organized all the code in here
we got the car superclass the superclass
is the main class that all of these
inherit from sports car truck and then
our two enumerations so we'll come back
here into for Mondavi b will zoom in
some so let's go ahead and go to the
designer and we'll just add a list box
that will hold all of our car or truck
or sports car objects so this box right
here we're making a little bit bigger
and we'll shrink it well bring it down
like that
now let's go ahead and bring it down a
little bit more and we're gonna add a
nother button so we'll come back to our
toolbox we have click button or we'll
add button one and we'll set the text to
new car and then we'll set the name to
button create car now we're not going to
be using that right now but we will
later on so we'll come back to form of a
beam and now what we're gonna need is a
an ArrayList that's gonna hold all of
our car objects
now we are gonna use an array list
because we don't know how many objects
the user is going to be adding to the
list box so we will type private cars as
new ArrayList okay so whenever our form
loads let's just go ahead and add these
two objects right here to our ArrayList
so we'll just type cars dot and and you
will then we'll add default car and we
will add the default sports car okay so
now that we have these two cars in our
ArrayList
let's go ahead and add all those items
to our form 1 or to our list box
let's go ahead and rename the list box
right here so it was call it list cars
and we'll come back in here and we'll
create a sub that will do this for us so
we'll type private sub add all cars and
this is just going to run once when the
form one loads so what we're going to do
is add all cars so we'll type for each
car as and then we want to do it of type
we'll do it of type all cars car
so you can see that we can use
polymorphism in this in this a for each
loop right here because we can pass a
car object we can use car objects in
this but we can also use sports cars and
trucks so how long such again in so our
ArrayList that we're gonna use for this
is cars so for each car as all cars car
in cars that might be a little confusing
but we're just going to go ahead and add
that to the list box right here now as I
was saying we're you're gonna use
polymorphism for this because we can
treat sports cars and trucks as a car
because they inherit from it so we don't
have to do a specific type in here so
we'll just type list cars dot em sad
they're just gonna add car dot car name
so this is gonna add our car name to the
list box so let's go ahead and run this
and it looks like we're getting an error
here so we got in speed is not
accessible so we're just gonna have to
make that stay here we're going to have
to use this property right here so we
can just go ahead and instead of typing
in speed we'll just type speed
so we're accessing the speed property
and not the variable itself okay so now
let's run this again and see if we get
the desired output looks like we're
gonna have to call that sub
so wolves type and all cars okay so now
it should work but before it will be
able to print out the car name of our
default car our default sports car we're
gonna have to actually set the name or
it's going to be printing out a no
object inside of our list box and then
you won't actually see it so it's not
the first one to will do a Honda CRV and
then for the sports car
we will just call it Mustang GT
so Mustang GT right there okay so now if
everything runs right hopefully we get
each car inside of our list box now we
can actually show the information of
each one of these different cars but
we'll be doing that in the next tutorial
as you can see if I select CRV it gives
us the Mustang GT info and that's not
exactly what we want so go ahead put
this code in if you haven't already and
then once you've done that go ahead and
move on to the next tutorial