Get visited percentage in course

HiThe only way to do this would be to create a variable that increases by the count of 1 each time a new page is seen.This may involve a set of variables to ensure once a page has added to the count it does not do it again. (this stops someone going from page 1 to page 2 then back to 1 again and thus increasing the count till 80% triggers) So each page has to have a variable that as default is 0, then as you enter the page for the first time you add an on-show action to add 1 to the count of the total viewed pages variable, on the condition the page variable =0 then modify the page variable =1Then its simple maths, create a button to say print certificate put it right at the top of the course so its on every page, initially hidden and only show it if the page count variable has reached a number equivalent to 80% of the total pages you have created. This can be done with an action on every page on-show , show, button , on condition the page count variable is high enough.Don't forget to make all variable persistent so they continue if the user exits and comes back.