Add Alert to Custom Indicator

I want to add an audible and visual alert to an existing custom indicator, as follows: When the Bollinger Bandwidth is less than X (default is 6) or greater than X (default is 24), pop up a box that tells me the currency pair and time frame and sound an alert. In other words -- if the distance between the upper and lower lines of the Bollinger Bands reach either of these predefined values, I want to see and hear an alert. ## Deliverables Custom Indicator is attached.