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Listings

  • Listing 1 . Complete listing for Skins01.mxml.
  • Listing 2 . Beginning of the class named Driver.
  • Listing 3 . The constructor for the Driver class.
  • Listing 4 . The method named buttonHandler.
  • Listing 5 . Beginning of the FancyButton class.
  • Listing 6 . Constructor for the FancyButton class.
  • Listing 7 . The toggleSkin method.
  • Listing 8 . Source code for the file named Skins01.mxml.
  • Listing 9 . Source code for the class named Driver.
  • Listing 10 . Source code for the class named FancyButton.
  • Listing 11 . Source code for the class named ButterflyButton.
  • Listing 12 . Source code for the class named FrogButton.

Supplemental material

I recommend that you also study the other lessons in my extensive collection of online programming tutorials. You will find a consolidated index at www.DickBaldwin.com .

General background information

The first major characteristic of an object-oriented program is encapsulation, which I explained in the previous lesson. The second of the threemajor characteristics is inheritance , followed by polymorphism . I will explain inheritance from a big-picture viewpoint in this lesson and will explain polymorphism in the next lesson.

A new class can extend an existing class

A class can be defined to inherit the properties, events, and methods of another class. From a syntax viewpoint, this is accomplished using the extends keyword.

The class being extended is often called the base class or the superclass , and the new class is often called the derived class or the subclass .

What is inherited?

The subclass inherits the data representation and behavior of the superclass (and all of its superclasses) . However, the subclass can modify the behavior of inherited methods by overriding them. (That will be one of the topics in the next lesson on polymorphism.) The subclass can also add new data representation and behavior that is unique to itsown purposes.

The superclass remains viable

A program can instantiate objects of a superclass as well as from its subclass. From a practical viewpoint, the superclass doesn't even knowthat it has been extended.

A hierarchy of classes

Inheritance is hierarchical. In other words, a class may be the subclass of one (and only one) other class and may be the superclass of one or more other classes.

For example, the ActionScript 3 Button class is a subclass of the UIComponent class, and is the superclass of the following classes:

  • AccordianHeader
  • CheckBox
  • LinkButton
  • PopUpButton
  • RadioButton
  • ScrollThumb
  • SliderThumb

An orderly hierarchy

Inheritance mechanisms allow you build an orderly hierarchy of classes.

When several of your abstract data types have characteristics in common, you can design their commonalities into a single superclass and separate theirunique characteristics into unique subclasses. This is one of the purposes of inheritance. (This purpose is illustrated by the program that I will explain later in this lesson.)

The airship hierarchy

For example, suppose you are building a program dealing with airships. All airships have altitude and range parameters in common. Therefore, you couldbuild a base Airship class containing data and methods having to do with range and altitude.

Questions & Answers

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.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
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
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
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali 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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