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The same thing happens if we do override the draw method but leave the body empty. Therefore, the physical creation of the display window isbeing accomplished in the framework by code outside the draw method. The draw method simply controls the contents of the display window.

Code in the Cars class

Instance variables of type Car

The code in the Cars class (see Listing 2 ) begins by declaring two instance variables of the class named Car . By default, these two instance variables are initialized to null, meaning that they don'tcontain references to objects.

The inherited size method

The setup method begins by calling the method named size , which is inherited from the PApplet class. The documentation for the size method reads partially as follows:

"Defines the dimension of the display window in units of pixels. The size() function must be the first line in setup() . If size() is not used, the default size of the window is 100x100 pixels. The system variables width and height are set by the parameters passed to this function.

Do not use variables as the parameters to size() function, because it will cause problems when exporting your sketch. Whenvariables are used, the dimensions of your sketch cannot be determined during export. Instead, employ numeric values in the size() statement, and then use the built-in width and height variables inside your program when the dimensions of the display window are needed.

The size() function can only be used once inside a sketch, and cannot be used for resizing."

The display window

In case you were wondering about the type of object shown in Image 1 , here is some information from the PApplet documentation.

"This class extends Applet instead of JApplet because 1) historically, we supported Java 1.1, which does not include Swing (without an additional,sizable, download), and 2) Swing is a bloated piece of crap. A Processing applet is a heavyweight AWT component, and can be used the same as any other AWTcomponent, with or without Swing.

Similarly, Processing runs in a Frame and not a JFrame. However, there's nothing to prevent you from embedding a PApplet into a JFrame, it's just thatthe base version uses a regular AWT frame because there's simply no need for Swing in that context. If people want to use Swing, they can embed themselves asthey wish."

Stated differently, the display window that you see in Image 1 is a standard java.awt.Frame object.

Instantiate Car objects

After setting the size of the display window, the setup method in Listing 2 instantiates two objects of the Car class and saves the object's references in the instance variables named myCar1 and myCar2 .

We haven't discussed the constructor for the Car class yet, but we can see in Listing 2 that the constructor for one Car object is passed a color value of pure red and the constructor for the other Car object is passed a color value of pure blue.

Let's talk about color

If you are an experienced Java programmer, what I am about to tell you is going to seem really strange.

Primitive types

As an experienced Java programmer, you know that the Java language defines the following eight primitive types:

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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