In your 1st listview builder why you fetching itemcount dynamically when user is not allowed to add generetype, you know right how many types are there here 3 so just keep item count 3 thats it and think logic for second nested

After creating static titles for your genere you can use if condition if that movie has genere this then add elses go to next condition and next till all movies are added to tbe respected genere

Please comment your search bar implementation and what is the work done by every variable passed to that search bar