Function parameters

Pass by Value

function passPrimitives(xParam:int, yParam:int):void
{
  xParam++;
  yParam++;
  trace(xParam, yParam);
}

var xValue:int = 10;
var yValue:int = 15;

trace(xValue, yValue);          // 10 15
passPrimitives(xValue, yValue); // 11 16
trace(xValue, yValue);          // 10 15

Pass by Reference

function passByRef(objParam:Object):void
{
  objParam.x++;
  objParam.y++;
  trace(objParam.x, objParam.y);
}

var objVar:Object = {x:10, y:15};

trace(objVar.x, objVar.y);  // 10 15
passByRef(objVar);          // 11 16
trace(objVar.x, objVar.y);  // 11 16

The objParam parameter references the same object as the global objVar variable. As you can see from the trace statements in the example, changes to the x and y properties of the objParam object are reflected in the objVar object.

AS3 : Dynamic classes

A dynamic class defines an object that can be altered at run time by adding or changing properties and methods. A class that is not dynamic, such as the String class, is a sealed class. You cannot add properties or methods to a sealed class at run time.

You create dynamic classes by using the dynamic attribute when you declare a class. For example, the following code creates a dynamic class named "DynamicClass".

Code : /*Main.as*/

package
{
 import flash.display.Sprite;

 public class Main extends Sprite
 {
  public function DynamicClassCode()
  {
   var dClass:DynamicClass = new DynamicClass();

   dClass.age = 25; // Dynamically add new variable.
   // Dynamically add new Method.
   dClass.getDetails = function():void 
   {
    trace(dClass.nama);
    trace(dClass.age);
   }
   
   dClass.getDetails(); // Method call
  }
 }
}

dynamic class DynamicClass
{
 public var nama:String = "Abdul";
}

Flex: Custom Tooltip - IToolTip

While Creating the Tooltip the main thing is, the particular component/control's attribute toolTip=" " must contain space or any char's, but should not be empty or null.

Sample Main: /*Main.mxml*/

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
    layout="vertical">

 <mx:Script>
  <![CDATA[
   import com.abdul.TipComp;
   import mx.events.ToolTipEvent;

   private function callTootTip(e:ToolTipEvent):void
   {
    var touchedLabel:String = e.target.label;

    var tc:TipComp = new TipComp();
    tc.setText = touchedLabel; // pass value to the component.

    e.toolTip = tc;
   }
  ]]>
 </mx:Script>

 <mx:Button label="Tool Tip Button"
      toolTip=" "
      toolTipCreate="callTootTip(event)"/>
</mx:Application>

Here,
1. In the user define component we have to implement the IToolTip interface like this implements="mx.core.IToolTip".
2. The setText (it is a user define method for our convenience) method is used to get the value from the caller.
3. Image is used as a ToolTip.

Sample Component: /*TipComp.mxml*/

<?xml version="1.0" encoding="utf-8"?>
<mx:VBox xmlns:mx="http://www.adobe.com/2006/mxml"
   implements="mx.core.IToolTip"
   horizontalAlign="center"
   verticalAlign="middle">

 <mx:Script>
  <![CDATA[
   import mx.core.IToolTip;
   
   [Bindable]
   private var value:String = "";

   /* used to get value from the caller */
   public function set setText(value:String):void
   {
    this.value = value;
   }

   public function set text(txt:String):void
   {
   }

   public function get text():String
   {
    return "";
   }
  ]]>
 </mx:Script>
 
 <mx:Label id="lab"
     text="{value}"/>
 <mx:Image x="87"
     y="10"
     height="280"
     width="226"
     source="@Embed(source='Earth_axis.jpg')"/>
</mx:VBox>