CODEWITHSUNDEEP
flashactionscriptactionscript-2
George Reith
George Reith

Reputation: 13476

AS2: call method when new property is set

I have a dynamic Class and what I would like to do is call a method everytime a property is appended to the class during run-time.

For example:

dynamic class Example
{

    public function Example()
    {
        trace("New instance created");
    }

    public function setter(name:String, value:String):Void
    {
        trace("Property '"+name+"' created with value '"+value+"'");
    }
}

And then from the timeline when I would add a new property to Example:

Example.newProperty = "some value";

I want it to trace:

Property 'newProperty' created with value ' some value'

I am fully aware that this is capable by using a function to set properties like so:

public function setter(name:String, value:String):Void
{
    this[name] = "some value";
    trace("Property '"+name+"' created with value '"+value+"'");
}

and calling it like so:

Example.setter("newProperty", "some value");

However I want this method to fire automatically when a property is added via the regular .dot operator and not have to call a function explicitly.

Is this possible?

Upvotes: 3

Views: 477

Answers (2)

Marty
Marty

Reputation: 39466

Could use Proxy here.

Example class:

package
{
    import flash.utils.Proxy;
    import flash.utils.flash_proxy;

    dynamic public class Example extends Proxy
    {

        private var _properties:Object = {};


        override flash_proxy function setProperty(name:*, value:*):void
        {
            _properties[name] = value;
            trace("Property '" + name + "' created with value '" + value + "'");
        }


        override flash_proxy function getProperty(name:*):*
        {
            return _properties[name];
        }

    }
}

Demo code:

var ex:Example = new Example();

ex.something = 10;
ex.more = "something more";

trace(ex.something);
trace(ex.more);

Output:

Property 'something' created with value '10'
Property 'more' created with value 'something more'
10
something more

Upvotes: 0

user797257
user797257

Reputation:

Since it's AS2, then, yes, your class has to implement __resolve(x) method. I would, however, consider it a very questionable design decision. The function that accepts the key and the value looks much better to me, and, in the end, it's less code.

Upvotes: 1

Related Questions