OOP, constructors. Why is the object null?

Question

Hi. Here's AS3 behavior that I don't quite understand. The code is:

public class TestA
{
      public var data:Object;

      public function TestA()
      {
           trace("From A", this.data);
     }

}

public class TestB extends TestA
{

     public function TestB()
     {
         //this.data = { test: 5 };
         this.data = new Object();
         trace("From B", this.data);
         super();
     }

}

import flash.display.Sprite;

public class TestApp extends Sprite
{
      public function TestApp()
      {
          var t:TestB = new TestB();
      }

}

This outputs

From B [object Object]
From A null

where I would expect

From B [object Object]
From A [object Object]

How come?

Using Flex 4 SDK with FlashDevelop.

Andrei1-bKoviI · Answer

Because by calling super() constructor you nullify the object.

Try this:

package
{
     public class TestA
     {
          public var data:Object;

          public function TestA()
          {
               trace("From A", this.data);
               getData();
          }
           
          public function getData():void
          {
               trace("From A", this.data);
          }

     }

}
package 
{
     public class TestB extends TestA
     {
          public function TestB()
          {
               data = new Object();
               trace("From B constructor", this.data);
               getData();
               thisData();
               super();
               getData();
               thisData();
          }
           
          private function thisData():void {
               trace("From B thisData", this.data);
          }

     }
}

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