I have built an FM radio program in gnu radio. I currently have a slider that I can use to change the channel I am listening to manually. I want to add on a scan button similar to cars where you click it and it scans for the next channel broadcasting on fm radio.

I have also uploaded my current flow chart from gnu radio. The tuning range variable I was originally going to use to tune manually but ended up just using the oringial channel_freq variable and made it a slider.

I tried adding a push button GUI but I do not know how to set it up to also affect the channel_freq variable