Describe flex component file types ?

There are following file types we can use in flex.

extension .mxml - a component implemented as an MXML file.

extension .as - a component implemented as an ActionScript class.

extension .swc - a SWC file contains components in a packge.

Difference between target & currentTarget ?

target : This property is set by the dispatchEvent() method. You cannot change this to a different object.

currentTarget : This property is set by component instance that is actively processing the event object.

How many type of components you can create in action script?

We can create two type of components using action script, which are as follows.

• User-interface, or visual, components
  
• Nonvisual components

What's MXML Components ?

MXML components are MXML files that is use in other mxml files just like a MXML tags. One of the main uses of MXML components is to extend the functionality of an existing Flex component & reusebility of custom components.

How many type of metadata tags can use in flex ?

Following metadata tags we can you in flex.

[Inspectable] - use to define an attribute exposed to component users in the attribute hints and Tag inspector.

[DefaultProperty] - use to define default property.

[Effect] - use to define effect.

[Embed] - use to import JPEG, GIF, PNG, SVG, and SWF files at compile time.

[ArrayElementType] - use for an Array.

[Bindable] - use to identify a property that you use tags

[IconFile] - use to identify icon file.

[Event] - use to define an event.

[NonCommittingChangeEvent] - use to identify an event as an interim trigger.

[Style] - use to define the MXML property for a style property.

[InstanceType] - use to specify the allowed data type of a property.

What is Metadata tags in flex ?

Metadata tags provide information to the Flex compiler that describe to flex compiler how your components
are used in a Flex application.

For example,

[Event(name="creationComplete", type=flash.events.Event)]

What is trace method ?

Trace is used to print value of variables in small window it is also refer as console output. It is basically used to testing variables or objects value.

For examples,

trace("show msg..");