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Will explain the code in fragments

I will explain the code for this Flex application in fragments. A complete listing of the application is provided in Listing 6 near the end of thelesson.

Beginning of XML code for SliderChangeEvent01

The primary purpose of this application is to illustrate the use of inline event handling for Flex 3 slider change events.

The application begins in Listing 2 which shows the beginning of the Application element and the two complete Label elements shown at the top of Figure 1.

Beginning of xml code for sliderchangeevent01.

<?xml version="1.0" encoding="utf-8"?><mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"><mx:Label text="Put your name here" fontSize="16" fontWeight="bold"/><mx:Label text="Image Height in Pixels" fontWeight="bold" fontSize="14"/>

Make it easy - drag and drop

The two Label elements were created by dragging Label controls from the Components tab shown in Figure 4 onto the Design tab shown in Figure 5. Then the attribute values were set using the Flex Properties tab shown in Figure 6.

The attributes shown in Listing 2 represent common properties of a text label and shouldn't require further explanation.

Create and condition the slider

Listing 3 adds a horizontal slider (HSlider) control to the application and sets the attributes that control both its appearance and itsbehavior.

Create and condition the slider.

<mx:HSlider minimum="100" maximum="250" value="250" toolTip="Height"change="myimg.height=event.currentTarget.value" liveDragging="true" />

The slider is a little more complicated than a label and deserves a more thorough explanation.

The numeric properties

Recall that a slider represents a range of numeric values. The position of the thumb at any instant in time selects a value from that range. Thefollowing three attributes shown in Listing 3 deal with the slider and its numeric range:

  • minimum - the numeric value represented by the left end of a horizontal slider.
  • maximum - the value represented by the right end of a horizontal slider.
  • value - the value that specifies the initial position of the thumb when the slider is constructed and first presented in the application'swindow.

The toolTip property

As you have probably already guessed, the value of the toolTip property specifies the text that appears in the tool tip when it is visible as shown in Figure 2.

The change property

This is where thing get a little more interesting. As the user moves the thumb to the left or right, the slider fires a continuous stream of change events. You might think of this as the slider yelling out "Hey, the position of my thumb has been changed." over and over as the thumb is being moved. (Also see the discussion of the liveDragging property later.)

An event handler

The value that is assigned to the change attribute in Listing 3 is often referred to as an event handler . This value specifies what the application will do each time the slider fires a change event.

Three ways to handle events in Flex

Questions & Answers

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.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
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 did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to xml. OpenStax CNX. Dec 02, 2014 Download for free at https://legacy.cnx.org/content/col11207/1.18
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