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Inherited methods

We can see from Listing 2 that our new class inherits a method named setup , a method named draw , and a method named size . The code in Listing 2 overrides the setup and draw methods and calls the size method without overriding it.

The class named PApplet defines a huge number of methods. Those methods can be called from within our class named Cars (by novice programmers) without knowledge of anything related to object-oriented programming. They look pretty-much like global function callsfrom the dark ages.

A function library

In effect, the authors of Processing have created a huge function library, (reminiscent of the function libraries of the dark ages of Pascal and C) . Novice programmers can use that library to create sketches using a proceduralprogramming style (as opposed to an object-oriented programming style) ..

A tricycle and a bicycle

While I don't think this is a good way to teach people how to program, I am impressed that the authors of Processing were able to pull it off.

In my opinion, learning to program this way is like trying to learn how to ride a bicycle by riding a tricycle. (I'm not talking about a bicycle with removable training wheels. I'm talking about a vehicle with three fixed wheels.)

As long as that tricycle (the PDE) will get you where you need to go, everything is okay. However, without specialeffort on your part, you will be ill-equipped to put the PDE aside and ride the bicycle (write object-oriented code ) if this is how you learn to program.

Understanding the anatomy of the framework

That having been said, by understanding the anatomy of the framework, it is possible for novices and experienced programmers alike

  • to think in object-oriented terms,
  • to write serious object-oriented programs using the PDE, and
  • to take advantage of the many libraries supported by Processing.

The ability to effectively use multiple libraries is one of the hallmarks of a successful OO programmer.

The draw method

The description of the draw method (that is inherited from the PApplet class) reads partially as follows:

"Called directly after setup() and continuously executes the lines of code contained inside its block until the program is stopped or noLoop() is called.

The draw() function is called automatically and should never be called explicitly.

It should always be controlled with noLoop(), redraw() and loop().

After noLoop() stops the code in draw() from executing, redraw() causes the code inside draw() to execute once and loop() will cause the code inside draw() to execute continuously again.

The number of times draw() executes in each second may be controlled with frameRate() function.

There can only be one draw() function for each sketch and draw() must exist if you want the code to run continuously or to process events such as mousePressed(). Sometimes, you might have an empty call to draw() in your program ..."

Default behavior of the framework

We know that the default behavior of the framework is to display a window on the screen similar to Image 1 if we don't override the draw method.

Questions & Answers

Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
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
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
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
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Source:  OpenStax, The processing programming environment. OpenStax CNX. Feb 26, 2013 Download for free at http://cnx.org/content/col11492/1.5
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