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Purpose of the class

The purpose of this class is to define the characteristics of an object that will serve as a driver to exercise and to illustrate the behavior of objects ofthe following custom classes:

  • ButterflyButton
  • FrogButton
  • FancyButton

Inheritance in action

Note that this class extends the standard Flex/ActionScript class named HBox . Thus, an object of the Driver class inherits all of the characteristics defined into the HBox class and adds more characteristics that are unique to an object of the Driver class.

For example, one of the important characteristics inherited from the HBox class is the ability to arrange child components horizontally as shown in Figure 2.

Instantiate custom button objects

Listing 2 instantiates objects of the three custom classes listed above and stores references to those objects in private instance variables with the following names:

  • bFlyButton
  • frogButton
  • fancyButton

Storing the references as private instance variables makes them accessible to the constructor and to methods defined within the Driver class, but makes them inaccessible otherwise.

The constructor for the Driver class

Listing 3 defines the constructor for the Driver class.

The constructor for the driver class.

public function Driver(){//constructor addChild(bFlyButton);addChild(frogButton); addChild(fancyButton);fancyButton.addEventListener(MouseEvent.CLICK,buttonHandler); }//end constructor

Listing 3 begins by adding the three objects instantiated in Listing 2 to the object being constructed, which is possible because an object of the Driver class is an HBox container. (See the earlier section titled The ISA relationship .)

Then Listing 3 registers a click event handler method named buttonHandler on the FancyButton object.

The method named buttonHandler

The click event handler method named buttonHandler is shown in Listing 4.

The method named buttonhandler .

private function buttonHandler( event:MouseEvent):void{fancyButton.toggleSkin(); }//end buttonHandler}//end class }//end package

This method is executed each time the FancyButton object fires a click event. When the method is executed, it calls the toggleSkin method on the FancyButton object. As you will see later, the toggleSkin method causes the FancyButton object to toggle its skins between butterfly images and frog images.

The end of the Driver class

Listing 4 also signals the end of the class named Driver .

The file named FancyButton.as

The FancyButton class begins in Listing 5. A complete listing of the class file is provided in Listing 10 near the end of the lesson.

Define a custom button using skins

This class defines a custom button using skins. When the program starts, frog images are used to define the button's skins as shown by the rightmost button inFigure 2. Each time the toggleSkin method is called, the skin switches between frog images and butterfly images.

Beginning of the fancybutton class.

package CustomClasses{ import mx.controls.Button;public class FancyButton extends Button{[Embed("/Images/frogup.jpg")] private var frogUp:Class;[Embed("/Images/frogover.jpg")] private var frogOver:Class;[Embed("/Images/frogdown.jpg")]private var frogDown:Class;[Embed("/Images/frogdisabled.jpg")] private var frogDisabled:Class;[Embed("/Images/bflyup.jpg")]private var bFlyUp:Class;[Embed("/Images/bflyover.jpg")] private var bFlyOver:Class;[Embed("/Images/bflydown.jpg")]private var bFlyDown:Class;[Embed("/Images/bflydisabled.jpg")] private var bFlyDisabled:Class;

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
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