Macromedia flex 2-migrating applications to flex 2 Manual De Usuario
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ActionScript 2.0 to 3.0
ActionScript 2.0 had many instances where getter and setter methods existed rather than
accessors. Now, ActionScript 3.0 uses accessors wherever possible. Unless a function has
arguments, it was converted to an accessor.
accessors. Now, ActionScript 3.0 uses accessors wherever possible. Unless a function has
arguments, it was converted to an accessor.
Methods that return a Boolean such as
Socket.isConnected()
were converted to accessors,
but retained the “is” or “has” prefix. For example, a method called methods would be
converted to the
converted to the
Socket.isConnected
property.
Internal functionality marked private
ActionScript 3.0 includes a greater number of classes and members that are marked private.
Prior to this, maybe private members were not marked appropriately and functionality that
was intended to be used internally was exposed.
Prior to this, maybe private members were not marked appropriately and functionality that
was intended to be used internally was exposed.
Naming conflicts with Flex classes
The Flex class library and the Flash Player API share similar class names, such as Buttons,
Images, and TextFields.
Images, and TextFields.
It is important that classes in the Flex classes and the Flash Player API not have the exact same
names. Even though the package system gives classes “long names” and helps partition
conflicting names away from each other, you might import many packages. If Flex and Flash
Player both have a class named Button, and you import both packages, the Flex compiler
throws ambiguity errors.
names. Even though the package system gives classes “long names” and helps partition
conflicting names away from each other, you might import many packages. If Flex and Flash
Player both have a class named Button, and you import both packages, the Flex compiler
throws ambiguity errors.
As a general rule, the Flex class library and Flash Player API do not use the same name for a
class any more.
class any more.
Integer constants in enumerations
In ActionScript 2.0, enumerations were often expressed using string constants. For instance,
the
the
TextField.align
property could be set to the strings
left
,
center
, or
right
.
ActionScript 3.0 generally uses integer constants instead of strings. Integer constants are
declared as
declared as
public static const
members of a class, usually with type uint. The naming
should be all uppercase with underscores separating words.
Using integer constants has benefits for performance, and makes it possible for typos and
other usage errors to be detected at compile-time.
other usage errors to be detected at compile-time.