You can achive this easily by using qsVariable extension Qlik Branch
- First you need to define a variable like 'vTopN' and give a default value like 5.
- Add the extension and give name same as your variable.
- Add alternative values to variable like 5,10,20,All
- On chart, go to dimension property,change limitation to 'Fixed Value' and put $(vTopN) in the expression field.
Note : For All option in variable, you should write an expression like count(total customer)
I added a sample app, you can look at the 'Sales Analysis' sheet.
Hope it will help.
Executive Dashboard.qvf 2.2 MB