Flex Interview Questions

• Both are used for the purpose of editing, but item renderer is used for displaying visual elements.
• Item editor is used for editing purpose. Item editor can pass data back from the particular control to save it as a new value for an item being edited. We can also use item renderer as editor by using Boolean property renders editor.
• Item renderer is used to format and display the contents in components whereas item editor allows us to edit the displayed content

Exclude (or Exclude Class) tag helps to control the set of choices, available in Flex Builder. But it never excludes the classes from linking. There is an MXML option that depends on how the application is been compiled. Generally, the classes that are included are those that are referenced from the root application or classes, either directly or via some other class that is referenced directly or not from the root application or classes.

Cairngorm architecture can be explained as the process of implementation of several design patterns in order to form a lightweight architectural framework. Cairngorm follows the process of separating the view and business logic. This process is known as the Model-View-Controller pattern or (MVC).

The types of Cairngorm architecture are as follows:

• Model Locator: This Stores all the application’s Value along with shared variables that too at one place.
• View: This allows one or more Flex components bundled just like a named unit, bound to data in the Model Locator.
• Front Controller: This receives Cairngorm event details and then works ahead to map them to the cairngorm commands as and when required.
• Command: This handles business logic, calls cairngorm Delegates or Commands, and other updates.
• Delegate: This is created by a command, and regulates the remote procedure calls and gives the results back to that old command.
• Service: This defines the remote procedure calls to connect to remote data stores.

Difference between array and array collection is as follows:

• Array Collection is a wrapper class based on Array.
• Array Collection includes sorting, filtering features apart from Array.
• Array Collection automatically refreshes/updates the view whenever the change happens in Array Collection.

In order to cancel the default behavior of the event, few classified ways of the event class can be used in event listener functions in order to affect the behavior. In this few events are associated with default behavior. Therefore in cases, the same event listener can cancel the behavior by using the prevent Default method. Prevent Default method will work only if the Cancellable property is true else it will not.