[feature request] Sender object

[yuewah]

Is it possible to get the sender object for the NGUI Event Handler of the following UIComponents
UICheckbox
UIPopupList
UISlider
UIInput

In the mean time, only UIButtonMessage can get the sender object.

For general C# UI Component like WinForm, the event handler usually have a sender object and event arg.
void button1_Click(object sender, System.EventArgs e)

[yuewah]

UIEventListener method may solve my problem.