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Flex Interview Questions 1:
What are the various lifecycle events of Flex components?

Flex Interview Answer 1:
Various lifecycle events of Flex Components are
preinitialize, initialize, creationComplete.

Flex Interview Questions 2:
Can you describe initialize lifecycle event of a Flex Component?


Flex Interview Answer 2:
For a Flex component, the life-cycle event initialize is raised when
the component has successfully created/instantiated self and all its
child components, but it has not laid out its child component(s)
on its container layout yet.

Flex Interview Questions 3:
Can you describe preinitialize lifecycle event of a component?

Flex Interview answer 3:
For a Flex component, preinitialize lifecycle event happens when this
component is instantiated, but all its child component(s) are not yet
created/instantiated.

Flex Interview Questions 4:
During initialize lifecycle event for a Flex component, can a Flex
component be able to use/call any of its chicld component in 
ActionScript command(s)?

Flex Interview answer 4:
Yes, as in the initialize lifecycle event for a Flex component has
already created/instantiated all its child component, so it can call
or use its chilc component in the ActionScript command(s).

Flex Interview Questions 5:
Can you describe creationComplete lifecycle event?

Flex Interview answer 5:
In the creationComplete lifecycle event, any Flex component that has
been successfully instantiated self and all its child component(s)
and has also laid out all child component(s) in its layout.

Flex Interview Questions 6:
How these lifecycle events of a Flex component are handled in MXML
and ActionScript ?

Flex Interview answer 6:
Like any other event, these lifecycle events can be configured as 
attributes of the MXML tag with a value as the method/function
that is defined in the ActionScript command(s).

->>>>>> Added by Author as of 24-Nov-2011:

Flex Interview Question :
How to instantiate all child elements when the application initializes?

Interview Answer:
By using creationPolicy with value as 'all' will automatically instanciates
all the child elements while application initializes.

Flex Interview Question :
Is it always a good idea to use creationPolicy as 'all' for child elements 
instantiation, or any factor one should consider/think while deciding value
for the creationPolicy attribute?

Interview Answer:
By using creationPolicy of value 'all', can have adverse impact on user
experience in case concerned application is complex enough to have many
child elements and each child element would take it's own time to instantiate,
and in this context user may feel a sense of delayed reponse in application
startup time. 

But the good aspect of using creationPolicy equals to 'all' is to have all child elements
reponse time reduced to minimum when these are invoked, as the instantiation of these
elements are already happened. In case creationPolicy is set to none, then
on invocation of the child element, the element will have to be instantiated
before execution.

Looking at this aspect, one has to have proper reason for using appropriate 
value for creationPolicy for any element.

Flex Interview Question :
Can you use Reflection using ActionScript 3.0 version?

Flex Interview Answer :
Yes, by using functions from flash.utils package, such as
flash.utils.getQualifiedSuperclassName
flash.utils.getQualifiedClassName
flash.utils.describeType
flash.utils.getDefinitionByName

Flex Interview Question : 
What is the use of flash.utils.describeType function from the ActionScript v3.0 
api?

Flex Interview Answer :
flash.utils.describeType can used to find out public methods, properties and events
attached to an object, that is being passed as an argument to describeType function.

Flex Interview Question :
What are the various categories/types of errors?

Flex Interview Answer :
There are two types of errors, such as synchronous errors and asynchronous errors.

Flex Interview Question :
How are the synchronous errors handled?

Flex Interview Answer :
By using "try ... catch ... finally" block one can capture and handle synchronous errors.

Fles Interview Question :
How are the asynchronous errors handled?

Flex Interview Answer :
Asynchronous errors are handled by defining appropriate error event listeners,
and attaching listener to potential instance/object that can throw these types
of errors.

Flex Interview Question :
Can you provide an example scenario where asynchronous error can occur?

Flex Interview Answer :
When there is any network activity for which there is no need for immediate
response to be received, and caller can carry on with further processing, 
without waiting for completion of the activity. Like for example if there
is a report that is to be generated querying historical data from database,
and during the process, network connectivity terminates/ceases to operate,
then there can be network error thrown to the called program in form of
event. This event can be handled by using appropriate listener/handler.

Flex Interview Question :
As of ActionScript version 3.0, can you be able to use Inheritence and 
Interface definitions to get benefits of Object Oriented Capabilities?

Flex Interview Answer :
Yes, as of ActionScript 3.0, interface keyword can be used to define interface
for a concrete implementation of any user defined class definition.

Inheritence of any class can be achived by extending any other class by using
extends keyword.

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