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From this superclass, you might derive a Balloon class and an Airplane class.

The Balloon class

The Balloon class might add variables and methods dealing with passenger capacity and what makes it go up (helium, hydrogen, or hot air) . Objects of the Balloon class would then be able to deal with altitude, range, passenger capacity, and what makes it go up.

The Airplane class

The Airplane class might add variables and methods dealing with engine type (jet or propeller) and cargo capacity. Objects of the Airplane class could then deal with altitude, range, engine type, and cargo capacity.

Three types of objects

Having created this hierarchy of classes, you could instantiate objects of type Airship , Balloon , and Airplane with the objects of each type having variables and methods to deal with those specialcharacteristics of the flying machine indicated by the name of the class.

From the general to the specialized

You may have noticed that in this hierarchical class structure, inheritance causes the structure to grow in a direction from most general to morespecialized. This is typical.

Single and multiple inheritance

C++ and some other object-oriented programming languages allow for multiple inheritance. This means that a new class can extend more than one superclass.This has advantages in some cases, but can lead to difficulties in other cases.

ActionScript 3 does not support multiple inheritance. Instead it supports a different mechanism called an interface that provides most of the benefits of multiple inheritance without most of the problems. I willexplain the ActionScript interface in a future lesson.

The ISA relationship

You will sometimes hear people speak of the ISA relationship when discussing OOP. The source of this terminology is more fundamental than you mayat first suspect.

Object-oriented designers often strive to use inheritance to model relationships where a subclass "is a kind of" the superclass. For example, a car "is a kind of" vehicle. A programmer "is a kind of" employee which in turn "is a kind of" person.

This relationship is called the ISA relationship. It's that simple.

Preview

Assume that you are working on children's games. You probably don't want to use buttons that cause your game program to look like a businessprogram. Instead, you might prefer to use bright-colored buttons that look like animals, flowers, or other child-pleasing objects such as butterflies andfrogs. (See Figure 1 for example.)

Characteristics in common

On the other hand, you want your buttons to exhibit all of the functionality of the standard ActionScript Button class. In other words, you want your new buttons to have many characteristics in common with the ActionScript Button class.

A new class may not be required. -- It is probably also possible to accomplish this using embeddedActionScript code, but I will go the class definition route to illustrate inheritance and to produce a "cleaner" solution.

Inheritance to the rescue

As it turns out, this is easy to accomplish by defining an ActionScript class for each of your new button types.

Questions & Answers

what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Object-oriented programming (oop) with actionscript. OpenStax CNX. Jun 04, 2010 Download for free at http://cnx.org/content/col11202/1.19
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