this code works great for canceling a selection which contains a file that is already queued up but it cancels the entire selection including files which have not yet been queued up. is there a way from preventing the queue up of only files that are present and allow the queue up of new files within the same selection?

 

for example:

if i have files 1,2,3, and 5 on the queue and then select files 1,2,3,4,and 5. i would like only file 4 to be queued up.

 

 

can this be done with your control?