Custom metadata in three simple steps.

Custom metadata in three simple steps.

1. Configure compiler

To new Flex project add : -keep-as3-metadata+=Meta1,Meta2 to 'additional compiler arguments'. Write your metadata tag names separated by comma.

Hint: Build SWC library with keep-as3-metadata, load it into project and use your tags in this project. You don't need to add compiler parameter again.

2. Write metadata

Example :

package
{
    [Meta2(param1 = "param 1 value")]
    public class TestClass
    {

        [Meta1(param1 = "param 1 value", param2 = "param 2 value")]
        public var test1:String;
       
       
        [Meta2(paramA = "param 1 value", paramB = "param 2 value")]
        public function get test2():String
        {
            return null;
        }
       
        public function set test2(val:String):void
        {
        }

        [Meta1(param1 = "param 1 value")]
        public function someMethod():void
        {
        };

    }
}

3. Use your metadata during runtime

Just : describeType(TestClass)

and lookup your data (I mean E4X) :

<type name="TestClass" base="Class" isDynamic="true" isFinal="true" isStatic="true">
  <extendsClass type="Class"/>
  <extendsClass type="Object"/>
  <accessor name="prototype" access="readonly" type="*" declaredBy="Class"/>
  <factory type="TestClass">


    <metadata name="Meta2">
      <arg key="param1" value="param 1 value"/>
    </metadata>


    <extendsClass type="Object"/>


    <method name="someMethod" declaredBy="TestClass" returnType="void">
      <metadata name="Meta1">
        <arg key="param1" value="param 1 value"/>
      </metadata>
    </method>


    <variable name="test1" type="String">
      <metadata name="Meta1">
        <arg key="param1" value="param 1 value"/>
        <arg key="param2" value="param 2 value"/>
      </metadata>
    </variable>


    <accessor name="test2" access="readwrite" type="String" declaredBy="TestClass">
      <metadata name="Meta2">
        <arg key="paramA" value="param 1 value"/>
        <arg key="paramB" value="param 2 value"/>
      </metadata>
    </accessor>


  </factory>
</type>

Good luck.