CApplication. It is the object behind Yii framework. It provides the functionalities needed to respond to a web request and it is the class responsible for the handling the MVC pattern in Yii.
An event object encapsulates the information about the event. For a mouse click, it could provide the button (left or right) which was clicked. The type of information this object carries vary according to how it is implemented. How do you create your own event object?
For a given web request, there could be many events which could occur on an object. If the object must respond to multiple events, then these events become unmanageable and encapsulate too much in one place that should probably be separated.
In this post, we will discuss a pattern for handling generated events by event generators themselves.