RAGHAVA NAIDU

Understanding JVM Internals | CUBRID Blog

noreply@blogger.com (raghava) — Fri, 10 Feb 2012 20:50:10 PST

Understanding JVM Internals | CUBRID Blog

Format Change to the Java Certified Professional Designation

noreply@blogger.com (raghava) — Tue, 20 Dec 2011 18:22:17 PST

SCJP designation introduced 10 years ago. Now there is no longer a Sun Certified Java Professional (SCJP) designation. Instead, the new vernacular is OCP, standing for Oracle Certified Professional.

At the most fundamental level, the JDK version being tested has been updated. The latest incarnation of the Java Professional designation from Oracle will be testing candidates on version 1.7 of the JDK, not Java 5 or Java 6, as the previous examinations did.

Other change to obtain certification is now two step process, which starts first with passing the Oracle Certified Associate exam, or as it’s referred to on Oracle’s certification site, the Java SE 7 Programmer I test. Once you pass the new Associate exam, you are then qualified to write the Java SE 7 Programmer II exam, and if you pass that, you’ll have gained your Java ProfessionaL designation

HTML5 Quick Learning Guide

noreply@blogger.com (raghava) — Fri, 09 Dec 2011 17:47:16 PST

Channel in BlazeDS

noreply@blogger.com (raghava) — Mon, 25 Jul 2011 19:15:26 PDT

What is Channel

Channels are Client side objects that encapsulate the connection behaviour between flex components and blazeds server.

What Channel will do

Channel formats and translates the message into a network specific form.

Channel communicates with corresponding end points on the BlazeDS server.

Channels impose an order to the flow of messages sent to the server and the order of corresponding responses to ensure that the interaction between the client and server occurs in a consistent and predictable fashion.

Where to configure channel

We define channels and endpoints in services-config.xml file

How to configure channel
<channels>
...
<channel-definition id="my-amf"
type="mx.messaging.channels.AMFChannel">
<endpoint url="http://servername:port/myapp/messagebroker/amf"
type="flex.messaging.endpoints.AMFEndpoint"/>
</channel-definition>
</channels>

Failed launch Flash Player - Flex Mojos

noreply@blogger.com (raghava) — Sat, 09 Oct 2010 10:01:42 PDT

When I am working with Maven and Flex with FlexMojos I come across the below error.

+ Error stacktraces are turned on.

[INFO] Scanning for projects...

[INFO] ------------------------------------------------------------------------

[INFO] Building firstApp Flex

[INFO] task-segment: [install]

[INFO] ------------------------------------------------------------------------

[INFO] [resources:resources {execution: default-resources}]

[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,

i.e. build is platform dependent!

[INFO] Copying 0 resource

[INFO] [flexmojos:compile-swf {execution: default-compile-swf}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[WARNING] Source file was not defined, flexmojos will guess one.

[INFO] Flex compiler configurations:

-compiler.accessible=false

-compiler.actionscript-file-encoding UTF-8

-compiler.allow-source-path-overlap=false

-compiler.as3=true

-compiler.debug=false

-compiler.es=false

-compiler.external-library-path E:\raghava\firstApp\target\classes\libraries\pla

yerglobal-9.swc

-compiler.fonts.local-fonts-snapshot E:\raghava\firstApp\target\classes\fonts.se

-compiler.fonts.managers flash.fonts.JREFontManager flash.fonts.AFEFontManager f

lash.fonts.BatikFontManager

-compiler.headless-server=false

-compiler.include-libraries=

-compiler.keep-all-type-selectors=false

-compiler.keep-generated-actionscript=false

-compiler.library-path E:\raghava\firstApp\target\classes\libraries\flex.swc E:\

raghava\firstApp\target\classes\libraries\framework.swc E:\raghava\firstApp\targ

et\classes\libraries\rpc.swc E:\raghava\firstApp\target\classes\libraries\utilit

ies.swc D:\Documents and Settings\Jagadesh\.m2\repository\com\adobe\flex\framewo

rk\framework\3.2.0.3958\framework-3.2.0.3958-en_US.rb.swc D:\Documents and Setti

ngs\Jagadesh\.m2\repository\com\adobe\flex\framework\rpc\3.2.0.3958\rpc-3.2.0.39

58-en_US.rb.swc

-compiler.locale en_US

-compiler.namespaces.namespace http://www.adobe.com/2006/mxml E:\raghava\firstAp

p\target\classes\config-3.2.0.3958\mxml-manifest.xml

-compiler.optimize=true

-compiler.source-path E:\raghava\firstApp\src\main\flex

-compiler.strict=true

-compiler.use-resource-bundle-metadata=true

-compiler.verbose-stacktraces=false

-default-background-color 8821927

-default-frame-rate 24

-default-script-limits 1000 60

-default-size 500 375

-metadata.date Sat Oct 09 09:40:02 PDT 2010

-metadata.localized-title firstApp Flex x-default

-target-player 9.0.0

-use-network=true

-verify-digests=true -static-link-runtime-shared-libraries=false -load-config=

-metadata.language+=en_US

[INFO] [resources:testResources {execution: default-testResources}]

[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,

i.e. build is platform dependent!

[INFO] skip non existing resourceDirectory E:\raghava\firstApp\src\test\resource

[INFO] [flexmojos:test-compile {execution: default-test-compile}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[WARNING] Test folder not foundE:\raghava\firstApp\src\test\java

[INFO] [flexmojos:test-run {execution: default-test-run}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[INFO] Running tests E:\raghava\firstApp\target\test-classes\TestRunner.swf

[WARNING] [LAUNCHER] Using regular flashplayer tests

[INFO] ------------------------------------------------------------------------

[INFO] Tests run: 0, Failures: 0, Errors: 0, Time Elapsed: 0 sec

[INFO] ------------------------------------------------------------------------

[ERROR] BUILD ERROR

[INFO] ------------------------------------------------------------------------

[INFO] Accept timed outE:\raghava\firstApp\target\test-classes\TestRunner.swf

[INFO] ------------------------------------------------------------------------

[INFO] Trace

org.apache.maven.lifecycle.LifecycleExecutionException: Accept timed outE:\ragha

va\firstApp\target\test-classes\TestRunner.swf

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(Defa

ultLifecycleExecutor.java:719)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLi

fecycle(DefaultLifecycleExecutor.java:556)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(Defau

ltLifecycleExecutor.java:535)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHan

dleFailures(DefaultLifecycleExecutor.java:387)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegmen

ts(DefaultLifecycleExecutor.java:348)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLi

fecycleExecutor.java:180)

at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)

at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)

at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)

at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:6

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.

java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces

sorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:585)

at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)

at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)

at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)

at org.codehaus.classworlds.Launcher.main(Launcher.java:375)

Caused by: org.apache.maven.plugin.MojoExecutionException: Accept timed outE:\ra

ghava\firstApp\target\test-classes\TestRunner.swf

at org.sonatype.flexmojos.test.FlexUnitMojo.tearDown(FlexUnitMojo.java:3

15)

at org.sonatype.flexmojos.test.FlexUnitMojo.execute(FlexUnitMojo.java:16

at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPlugi

nManager.java:490)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(Defa

ultLifecycleExecutor.java:694)

... 17 more

Caused by: org.sonatype.flexmojos.test.TestRunnerException: Accept timed outE:\r

aghava\firstApp\target\test-classes\TestRunner.swf

at org.sonatype.flexmojos.test.DefaultTestRunner.run(DefaultTestRunner.j

ava:87)

at org.sonatype.flexmojos.test.FlexUnitMojo.run(FlexUnitMojo.java:279)

at org.sonatype.flexmojos.test.FlexUnitMojo.execute(FlexUnitMojo.java:16

... 19 more

Caused by: java.net.SocketTimeoutException: Accept timed out

at java.net.PlainSocketImpl.socketAccept(Native Method)

at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:384)

at java.net.ServerSocket.implAccept(ServerSocket.java:450)

at java.net.ServerSocket.accept(ServerSocket.java:421)

at org.sonatype.flexmojos.test.monitor.AbstractSocketThread.openClientSo

cket(AbstractSocketThread.java:124)

at org.sonatype.flexmojos.test.monitor.AbstractSocketThread.run(Abstract

SocketThread.java:62)

at java.lang.Thread.run(Thread.java:595)

[INFO] ------------------------------------------------------------------------

[INFO] Total time: 53 seconds

[INFO] Finished at: Sat Oct 09 09:40:27 PDT 2010

[INFO] Final Memory: 20M/63M

[INFO] ------------------------------------------------------------------------

E:\raghava\firstApp>mvn -e install

+ Error stacktraces are turned on.

[INFO] Scanning for projects...

[INFO] ------------------------------------------------------------------------

[INFO] Building firstApp Flex

[INFO] task-segment: [install]

[INFO] ------------------------------------------------------------------------

[INFO] [resources:resources {execution: default-resources}]

[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,

i.e. build is platform dependent!

[INFO] Copying 0 resource

[INFO] [flexmojos:compile-swf {execution: default-compile-swf}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[WARNING] Source file was not defined, flexmojos will guess one.

[INFO] Flex compiler configurations:

-compiler.accessible=false

-compiler.actionscript-file-encoding UTF-8

-compiler.allow-source-path-overlap=false

-compiler.as3=true

-compiler.debug=false

-compiler.es=false

-compiler.external-library-path E:\raghava\firstApp\target\classes\libraries\pla

yerglobal-9.swc

-compiler.fonts.local-fonts-snapshot E:\raghava\firstApp\target\classes\fonts.se

-compiler.fonts.managers flash.fonts.JREFontManager flash.fonts.AFEFontManager f

lash.fonts.BatikFontManager

-compiler.headless-server=false

-compiler.include-libraries=

-compiler.keep-all-type-selectors=false

-compiler.keep-generated-actionscript=false

-compiler.library-path E:\raghava\firstApp\target\classes\libraries\flex.swc E:\

raghava\firstApp\target\classes\libraries\framework.swc E:\raghava\firstApp\targ

et\classes\libraries\rpc.swc E:\raghava\firstApp\target\classes\libraries\utilit

ies.swc D:\Documents and Settings\Jagadesh\.m2\repository\com\adobe\flex\framewo

rk\framework\3.2.0.3958\framework-3.2.0.3958-en_US.rb.swc D:\Documents and Setti

ngs\Jagadesh\.m2\repository\com\adobe\flex\framework\rpc\3.2.0.3958\rpc-3.2.0.39

58-en_US.rb.swc

-compiler.locale en_US

-compiler.namespaces.namespace http://www.adobe.com/2006/mxml E:\raghava\firstAp

p\target\classes\config-3.2.0.3958\mxml-manifest.xml

-compiler.optimize=true

-compiler.source-path E:\raghava\firstApp\src\main\flex

-compiler.strict=true

-compiler.use-resource-bundle-metadata=true

-compiler.verbose-stacktraces=false

-default-background-color 8821927

-default-frame-rate 24

-default-script-limits 1000 60

-default-size 500 375

-metadata.date Sat Oct 09 09:50:02 PDT 2010

-metadata.localized-title firstApp Flex x-default

-target-player 9.0.0

-use-network=true

-verify-digests=true -static-link-runtime-shared-libraries=false -load-config=

-metadata.language+=en_US

[INFO] [resources:testResources {execution: default-testResources}]

[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,

i.e. build is platform dependent!

[INFO] skip non existing resourceDirectory E:\raghava\firstApp\src\test\resource

[INFO] [flexmojos:test-compile {execution: default-test-compile}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[WARNING] Test folder not foundE:\raghava\firstApp\src\test\java

[INFO] [flexmojos:test-run {execution: default-test-run}]

[INFO] Flexmojos 3.7

[INFO] Apache License - Version 2.0 (NO WARRANTY) - See COPYRIGHT file

[INFO] Running tests E:\raghava\firstApp\target\test-classes\TestRunner.swf

[WARNING] [LAUNCHER] Using regular flashplayer tests

[INFO] ------------------------------------------------------------------------

[ERROR] BUILD ERROR

[INFO] ------------------------------------------------------------------------

[INFO] Failed to launch Flash Player. Probably java was not able to find flashp

layer.

Make sure flashplayer is available on PATH

or use -DflashPlayer.command=${flashplayer executable}

Read more at: https://docs.sonatype.org/display/FLEXMOJOS/Running+unit+tests

CreateProcess: FlashPlayer.exe E:\raghava\firstApp\target\test-classes\TestRunne

r.swf error=2

[INFO] ------------------------------------------------------------------------

[INFO] Trace

org.apache.maven.lifecycle.LifecycleExecutionException: Failed to launch Flash P

layer. Probably java was not able to find flashplayer.

Make sure flashplayer is available on PATH

or use -DflashPlayer.command=${flashplayer executable}

Read more at: https://docs.sonatype.org/display/FLEXMOJOS/Running+unit+tests

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(Defa

ultLifecycleExecutor.java:719)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLi

fecycle(DefaultLifecycleExecutor.java:556)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(Defau

ltLifecycleExecutor.java:535)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHan

dleFailures(DefaultLifecycleExecutor.java:387)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegmen

ts(DefaultLifecycleExecutor.java:348)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLi

fecycleExecutor.java:180)

at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)

at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)

at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)

at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:6

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.

java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces

sorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:585)

at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)

at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)

at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)

at org.codehaus.classworlds.Launcher.main(Launcher.java:375)

Caused by: org.apache.maven.plugin.MojoExecutionException: Failed to launch Flas

h Player. Probably java was not able to find flashplayer.

Make sure flashplayer is available on PATH

or use -DflashPlayer.command=${flashplayer executable}

Read more at: https://docs.sonatype.org/display/FLEXMOJOS/Running+unit+tests

at org.sonatype.flexmojos.test.FlexUnitMojo.run(FlexUnitMojo.java:291)

at org.sonatype.flexmojos.test.FlexUnitMojo.execute(FlexUnitMojo.java:16

at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPlugi

nManager.java:490)

at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(Defa

ultLifecycleExecutor.java:694)

... 17 more

Caused by: org.sonatype.flexmojos.test.launcher.LaunchFlashPlayerException: Fail

ed to launch Flash Player.

at org.sonatype.flexmojos.test.launcher.AsVmLauncher.runFlashplayer(AsVm

Launcher.java:126)

at org.sonatype.flexmojos.test.launcher.AsVmLauncher.start(AsVmLauncher.

java:102)

at org.sonatype.flexmojos.test.DefaultTestRunner.run(DefaultTestRunner.j

ava:75)

at org.sonatype.flexmojos.test.FlexUnitMojo.run(FlexUnitMojo.java:279)

... 20 more

Caused by: java.io.IOException: CreateProcess: FlashPlayer.exe E:\raghava\firstA

pp\target\test-classes\TestRunner.swf error=2

at java.lang.ProcessImpl.create(Native Method)

at java.lang.ProcessImpl.(ProcessImpl.java:81)

at java.lang.ProcessImpl.start(ProcessImpl.java:30)

at java.lang.ProcessBuilder.start(ProcessBuilder.java:451)

at java.lang.Runtime.exec(Runtime.java:591)

at java.lang.Runtime.exec(Runtime.java:464)

at org.sonatype.flexmojos.test.launcher.AsVmLauncher.runFlashplayer(AsVm

Launcher.java:122)

... 23 more

[INFO] ------------------------------------------------------------------------

[INFO] Total time: 35 seconds

[INFO] Finished at: Sat Oct 09 09:50:08 PDT 2010

[INFO] Final Memory: 20M/63M

[INFO] ------------------------------------------------------------------------

As per the life cycle mojos trying to run unit test and unable to find flashplayer. To resolve this I have downloaded flashplayer exe file added to PATH. Again I got the same problem. Now I renamed the download flashplayer name to flashplayer.exe, my build completed successfully.

Actionscript performance - Try to use Integers (int) for all possible cases

noreply@blogger.com (raghava) — Mon, 30 Aug 2010 19:19:03 PDT

It is a good practice to use int in place of Number if the type int can able to satisfy your requirements. First we will see the difference between int,uint and Number.

uint - values ranging from 0 to 4,294,967,29 (positive numbers)
int - values ranging from -2,147,483,648 to 2,147,483,647
Number -can have values ranging far beyond int and uint and can include a decimal point

Among above three int type is faster follwed by Number. In looping always use int in place of Number.

Avoid:


var l:int = myArray.length;
for(var i:Number=0; i<l;i++>
{
 ............
}

Use:

var l:int = myArray.length;
for(var i:int=0; i<l;i++>
{
 ............
}

Flex ArrayList vs ArrayCollection

noreply@blogger.com (raghava) — Sat, 21 Aug 2010 11:27:21 PDT

Flex 4 introduced new collection ArrayList. ArrayList and ArrayCollection both are used to manipulate and store listdata. The key differences between ArrayList and ArrayCollection are

ArrayList is lighter version of ArrayCollection
With ArrayCollection we can sort and filter listdata and it is not possible with ArrayList

Action Script Event Listener - Weak Referencing

noreply@blogger.com (raghava) — Sun, 20 Jun 2010 05:35:30 PDT

Flash Player and AIR use a technique called garbage collection to clear objects from memory that are no longer in use. An object is considered no longer in use if no references to it exist. The garbage collector disregards weak references, which means that a listener function that has only a weak reference pointing to it is eligible for garbage collection.

In Action Script, we use addEventListener method to attach an event listener. It includes the bellow parameters:

eventName:String,
listener:Object,
useCapture:Boolean=false,
priority:Integer=0,
useWeakReference:Boolean=false

The useWeakReference parameter allows us to specify whether the reference to the listener function is weak or normal. Setting this parameter to true allows us to avoid situations in which listener functions persist in memory even
though they are no longer needed.

For example:

btn.addEventListener(MouseEvent.CLICK, clickHandler,false,0,true);

FlexAtBeach Chennai

noreply@blogger.com (raghava) — Sun, 13 Jun 2010 07:57:11 PDT

Last week Chennai hosted FlexAtBeach. I was very happy to be part of it. Thanks Devraj and adamstudio for this event. Hope we will have some more events like this in chennai.

Two sessions are very useful and new to me.

Andriod with Flash - Harish Sivaram, Adobe. (harish blog: http://blog.flexgeek.in/)
Swiz framework - Devraj (devraj blog : http://nsdevaraj.wordpress.com/)

For the content relating to the event click here

Adobe Flash Platform Summit at Bangalore

noreply@blogger.com (raghava) — Fri, 11 Jun 2010 11:08:45 PDT

Adobe Flash Platform summit coming to bangalore.

Flex ValidateNow() method

noreply@blogger.com (raghava) — Wed, 09 Jun 2010 10:59:57 PDT

The validateNow() method validates and updates the properties and layout of the control, and then redraws it, if necessary.

In some situations we may need to do some immediate operations like expand,collapse on the controls like advanceddatagrid after setting the data provider. There might be a situation layout is not adjusted with the latest data provider.

If we want to adjust immediately after setting the data to the dataproiver then call validateNow() method and then it creates and adjust the layout.

example:
advancedGrid.validateNow();

Flex 3 View States Vs Flex 4 View States

noreply@blogger.com (raghava) — Sun, 13 Jun 2010 00:36:26 PDT

One of the best change made from Flex 3 to Flex 4 is states. In flex 4 using of states made very simpler.

Here I am going to explain states in flex 3 and flex 4. For example

If user clicks admin button display "welcome Admin"
If user clicks user button display "welcome User"

Here is the code if we use flex 3:


<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="absolute" minWidth="955" minHeight="600">
<mx:states>
<mx:State name="admin">
<mx:AddChild position="lastChild" relativeTo="{displayBox}">
<mx:Label text="Admin" />
</mx:AddChild>
</mx:State>
<mx:State name="user">
<mx:AddChild position="lastChild" relativeTo="{displayBox}">
<mx:Label text="User" />
</mx:AddChild>
</mx:State>
</mx:states>
<mx:VBox>
<mx:HBox>
<mx:Button id="adminButton" label="Admin" click="this.currentState='admin'"/>
<mx:Button id="userButton" label="User" click="this.currentState='user'"/>
</mx:HBox>
<mx:HBox id="displayBox">
<mx:Label text="Welcome " />
</mx:HBox>
</mx:VBox>
</mx:Application>

In Flex 4:


<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Declarations>
<!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>
<s:states>
<s:State name="admin"/>
<s:State name="user"/>
</s:states>
<mx:VBox>
<mx:HBox>
<mx:Button id="adminButton" label="Admin" click="this.currentState='admin'"/>
<mx:Button id="userButton" label="User" click="this.currentState='user'"/>
</mx:HBox>
<mx:HBox id="displayBox">
<mx:Label text="Welcome " />
<mx:Label text="Admin" includeIn="admin" />
<mx:Label text="User" includeIn="user" />
</mx:HBox>
</mx:VBox>
</s:Application>

Flex 4 and Flash Builder 4 released

noreply@blogger.com (raghava) — Tue, 23 Mar 2010 11:32:08 PDT

Good News for Flex Developers. New versions Flex 4(Gumbo) and Flash Builder 4(earlier Flex Builder) are released with very good features. for more information : click here

Some of the useful links for Flex 4.

Forcing the browser to save a download with a given name using Content-Disposition

noreply@blogger.com (raghava) — Sun, 14 Feb 2010 03:41:44 PST

If we want to download any file with a given name then add Content-Disposition header to the response.

response.setHeader("Content-Disposition", "attachment;filename=myName.pdf");

Some times we may need to include the file always in the browser then in place of attachment specify inline.

response.setHeader("Content-Disposition", "inline;filename=myName.pdf");

Declaration tag in Flex 4

noreply@blogger.com (raghava) — Fri, 05 Feb 2010 12:45:53 PST

upto Flex 3, Application root we can include visual, non-visual children. For example I can write a date formatter, validator or any other non-visual elements directly under Application root tag.

From Flex 4, non visual components that represents new property declarations can not be written immediately under Application root tag. Non visual components has to be in side of declaration tag which is introduced in Flex 4.

<fx:Declarations>
<fx:Declarations/>

Two way data binding in Flex 4

noreply@blogger.com (raghava) — Fri, 05 Feb 2010 12:14:00 PST

One of the new feature introduced in Flex 4 is birectional (two way) binding. In flex 3 we can do only one way binding.

For example if want to do the two way binding you need to bind twice in flex 3.


<mx:TextInput id="myTextInput1" text="{myTextInput2.text}"/>
<mx:TextInput id="myTextInput2" text="{myTextInput1.text}"/>

In Flex 4 we can achieve the same as shown below.


<mx:TextInput id="myTextInput1" text="@{myTextInput1.text}"/>
<mx:TextInput id="myTextInput2" />

Calling Javascript function from Flex Application

noreply@blogger.com (raghava) — Sat, 02 Jan 2010 22:18:26 PST

Sometimes we may required to communicate JavaScript from Flex. Using ExternalInterface we can call javascript function from flex. Here is the simple example.



<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" 
    creationComplete="javaScriptFunctionCall()">
 
<mx:Script>
<![CDATA[

import flash.external.*;

public function javaScriptFunctionCall():void
{
 var jsFunctionName:String = "sayHello";
 
 if(ExternalInterface.available)
 {
  ExternalInterface.call(jsFunctionName, "Hello World");
 }

}
]]>
</mx:Script>

</mx:Application>

And the javascript function needs to be available in the html.


<script language="javascript">
function sayHello(info)
{
alert( info );
}
</script>

ActionScript Looping: Difference between for..in and for..each..in

noreply@blogger.com (raghava) — Tue, 22 Dec 2009 03:21:42 PST

We can use for..in to iterate through the elements of an array or properties of an object.



var studentObj:Object = {sno:1, sname:raghava};

for (var i:String in studentObj)
{
  trace(i + "= " + studentObj[i]);
}

Here we are iterating through the student object.

output:

sno= 1
sname= raghava

Similarly we can iterate though elements of the array using for..in


var array:Array = ["A", "B", "C"];
for (var i:String in array)
{
  trace(array[i]);
}

output:
A
B
C

The for each..in loop iterates through the items of a collection.


var countryXML:XML = 
India
USA
UK
;

for each (var country in countryXML.country)
{
  trace(country);
}

similary we can get the values in object.


var studentObj:Object = {sno:1, sname:raghava};

for each (var element in studentObj)//
{
  trace(element);
}

output:
1
raghava

The difference between for..in and for each..in

for each..in loop to iterate through the properties of a generic object and the iterator variable in a for each..in loop contains the value held by the property.

for..in loop to iterate through the properties of a generic object and the iterator variable in a for..in loop contains the name of the property.

Flex - Display a tool tip with the whole text when ellipsis are displayed on Datagrid column header

noreply@blogger.com (raghava) — Wed, 16 Dec 2009 10:41:06 PST

If the datagrid column contains so many columns or the header contains large text then it is not possible for us to show all the data. For that the best thing is we can show the content with ellipses(...) and provide a tooltip to show the actual data.

To implement the same in Flex, the best way is to use Label as headerRenderer. Since Label always display in a line and show ellipses and tool tip if it not fits in to the specified size.

We just need to specify the header Renderer as a Label .

dataGridCol.headerRenderer = new ClassFactory(Label);

Same has been implemented in the below example:
http://blog.flexexamples.com/2008/02/08/displaying-tool-tips-in-a-flex-datagrid-controls-header/

If you want to show tooltip in all datagrid columns follow this example.

http://flexdevtips.blogspot.com/2009/07/datagridcolumn-header-tooltips.html

Flash Builder 4

noreply@blogger.com (raghava) — Sun, 13 Dec 2009 04:38:36 PST

Flex builder 3,eclipse based IDE and it was a very good IDE to build flex applications. Now adobe planning to come up with New version by this summer. Now beta 2 is available for download.

Interesting thing here is Adobe changed the name from next version. Flex builder name changed to Flash Builder means the next release will be Flash Builder 4.

The name change is to maintain consistency. This IDE used as development tool for the Flash Platform and hence given the name Flash builder.

Links
------

Download:

http://www.adobe.com/cfusion/entitlement/index.cfm?e=labs_flashbuilder4

What's new in Flash Builder 4:

Tim's Article

Video

Tutorials

http://labs.adobe.com/technologies/flashbuilder4/tutorials/

http://www.adobe.com/devnet/flex/videotraining/flex4beta/index.html

Flex file types

noreply@blogger.com (raghava) — Sun, 13 Dec 2009 02:08:11 PST

When we are working with flex applications we come across the following different types of files.

.mxml - This is a mxml file used to define user interface.

.as - ActionScript file. ActionScript files can be used to define your business logic. It can be a ActionScript class or interface.

.swf - When the flex application compiled, .swf file will be created

.swc - Flex custom library file or unsignied RSL.

.swz - Adobe Flex Signed RSL

Flex 3 runtime-shared-libraries (RSLs)

noreply@blogger.com (raghava) — Sun, 13 Dec 2009 01:50:49 PST

Runtime shared libraries introduced in Flex 3. Flex runtime shared libraries reduces the size of the applications and hence the download time also reduced.

When we compile flex application, it will be formed as a swf file. This swf file contains all the required files for that specific application. Here there will be possibility of having same content in different swfs event though they are in the same project.

If we use the runtime shared libaries, first time shared contents will be dowloaded and stored in cache and next time used from the cache. This reduces the size of swf files and also reduces the download time.

There are two kinds of runtime shared libraries.

signed

Signed RSLs have a "swz" extension.
Signed by Adobe
Stored in the Flash Player Cache.
Can be accessed by applications from any domain

unsigned

Normal SWF files
Rely on the browser's cache

Flex - How to identify when the data provider of a DataGrid control changes

noreply@blogger.com (raghava) — Sat, 14 Nov 2009 17:37:07 PST

If we want to detect and do something when the data provider of a Datagrid control use CollectionEvent. We need to add the event listener like this.

dataGrid.addEventListener(CollectionEvent.COLLECTION_CHANGE, myMethod);

Example:

http://blog.flexexamples.com/2008/12/16/detecting-when-the-data-provider-of-a-datagrid-control-changes-in-flex/

FlexFormatter - Formatting tool for Flex builder

noreply@blogger.com (raghava) — Sat, 14 Nov 2009 16:58:58 PST

When you are coding, often you missed out formatting your source code adhering to the coding standards. It is very good to have a tool which covers this. When I am searching for a plugin to format flex code, I found FlexFormatter.

FlexFormatter is a eclipse plug-in for formatting ActionScript and mxml source code.

FlexFormatter has the following features.

Code Formatting
Auto Commenting
Source Code Reordering

Download:

http://sourceforge.net/projects/flexformatter/

Install and Use

If you have downloaded using the above link, then unzip the zip downloaded and copy the plug-ins to your flex builder plug-ins folder. Restart the flex builder to get the changes.

We can also install by using Software updates option. Follow the steps mentioned in the below link to install using software updates. Here you can also see how to use FlexFormatter.

http://kbala.com/2009/05/code-formatter-for-flex-builder/

Switching from PureMVC Standard to PureMVC multicore

noreply@blogger.com (raghava) — Mon, 09 Nov 2009 10:06:29 PST

When we are building flex application in a modular approach, PureMVC multicore is the best framework to use.

If your application is in PureMVC standard singlecore framework and wants to move to PureMVC multicore we have to do the following changes.

Remove the puremvc standard singlecore version library from your lib folder.
Add the puremvc multicore version library into project lib folder.
All the references of the singlecore version has to change to multicore. For this search for "org.puremvc.as3" and replace with "org.puremvc.as3.multicore" for that project.

Change the getInstance method of the Facade.

public static function getInstance( key:String ) : ApplicationFacade
    {
        if ( instanceMap[ key ] == null ) 
             instanceMap[ key ] = new ApplicationFacade( key );
        return instanceMap[ key ] as ApplicationFacade;
    }

To get the reference of the facade call getInstance method by sending the key.


        private var facade:ApplicationFacade    = ApplicationFacade.getInstance(  "KEY" );