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Some things can't be learned gradually

The remaining two challenges cannot easily be met on a gradual basis. Many aspects of OOP must be understood before a programmer can successfully write OOprograms

A slightly more technical description of OOP

An introductory description of OOP can be based on the guideline in Figure 1.

Guideline for oop.

The solution to the problem should resemble the problem, and observers of the solution should be able to recognize the problem withoutnecessarily knowing about it in advance.
Guideline for OOP.

For example, an OO program that deals with banking transactions should be recognizable on the basis of the objects that it uses, such as deposit objects,withdrawal objects, account objects, etc.

Flex is a good example

Many "application frameworks" are written according to the OOP paradigm. Important among these is Adobe's Flex, which can be used to simplify thedevelopment of the graphical user interface (GUI) portions of ActionScript programs.

Flex makes it possible to use uncomplicated XML syntax to access and use the ActionScript class library. Adobe's Flash Builder 4 makes the process evenmore straightforward by providing a largely drag-and-drop visual development environment for creating the GUI portion of ActionScript programs.

All of the components that are available in Flex are objects created from classes in the ActionScript library. Those classes have names like Button , RadioButton , and NumericStepper (see Figure 2) .

Three important concepts

Any object-oriented language must support three very important concepts:

  • Encapsulation,
  • Inheritance,
  • Polymorphism.

We use these three concepts extensively as we attempt to model the real-world problems that we are trying to solve with our object-oriented programs. Iwill provide brief descriptions of these concepts in the remainder of this lesson and explain them in detail in future lessons.

Encapsulation example

Consider the steering mechanism of a car as a real-world example of encapsulation. During the past eighty years or so, the steering mechanism for the automobile has evolved into an object in the OOP sense.

Only the interface is exposed

In particular, most of us know how to use the steering mechanism of an automobile without having any idea whatsoever how it is implemented. Allmost of us care about is the interface , which we often refer to as a steering wheel. We know that if we turn the steering wheel clockwise, the carwill turn to the right, and if we turn it counterclockwise, the car will turn to the left.

How is it implemented?

Most of us don't know, and don't really care, how the steering mechanism is actually implemented "under the hood." In fact, there are probably a number of different implementations for various brands and models ofautomobiles. Regardless of the brand and model, however, the human interface is pretty much the same. Clockwise turns to the right,counterclockwise turns to the left.

As in the steering mechanism for a car, a common approach in OOP is to "hide the implementation" and "expose the interface" through encapsulation.

Inheritance example

Another important aspect of OOP is inheritance . Let's form an analogy with the teenager who is building a hotrod. That teenager doesn't normally startwith a large chunk of steel and carve an engine out of it. Rather, the teenager will usually start with an existing engine and make improvements to it.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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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