property-observers.md

description
Observe any property and react!

Property Observers

WireBox supports the concepts of component property observers. Meaning that you can define a function that will be called for you when the setter for that property has been called and thus observe the property changes within a component.

You will accomplish this by tagging a property with an annotation called observed and created a function called: {propertyName}Observer by convention. This function will receive three arguments:

• newValue : The value that will be set into the property
• oldValue : The old value of the property, including null
• property : The name of the property

component{

	property name="data" observed;

	/**
	 * Observer for data changes.  Anytime data is set, it will be called
   	 *
	 * @new The new value
	 * @old The old value
	 * @property The name of the property observed
	 */
	function dataObserver( newValue, oldValue, property ){
		// Execute after data is set
	}

}

If you don’t like the convention and want to name the function as you see fit, then you can place the value of the observed annotation as the name of the function to call.

component{

	property name="data" observed="myObserver";

	/**
	 * Observer for data changes.  Anytime data is set, it will be called
  	 *
	 * @new The new value
	 * @old The old value
	 * @property The name of the property observed
	 */
	function myObserver( newValue, oldValue, property ){
		// Execute after data is set
	}

}

Please note that the observer will be called AFTER the property has been set. That's it, enjoy!