ActionScript 3 Error: 1046: Type was not found or....

Hi,

I am completely new to Flas and AS3. I am trying to create an opacity slider using the slider component. I foudn a similar tutorial and tried to alter it to fit my opacity needs. In line 8 (function opacityChange (event:SliderEvent):void{) I get the error message 1046. When I test it in Flash the slider flickers on and off very rapidly too. Though I have searched, I am clueless as to what the problem is.

Any help will be appreciated.

Thanks!!

importfl.events.SliderEvent;

percent_txt.text = "Opacity %:0";

slider.value = 0;

slider.addEventListener(SliderEvent.CHANGE,opacityChange);

function opacityChange (event:SliderEvent):void{

          percent_txt.text = "Opacity %: " + event.target.value;

          logo.alpha = event.target.value;

}