I'm working with my app that plays some video source (actually with exoplayer) on my phone, very easy. Now I'd like to add cast function to send videos to my tv. I follow some guide (like this https://developers.google.com/cast/docs/android_sender/integrate) but I'm a bit confused. The guide invites me to register a receiver app on Google Cast SDK Developer Console but I don't wanna make a receiver app, I just wanna add a simple cast button that allowed me to search and connect phone with some receiver. In particular the guide ask me to put the app_id of receiver app in my code, I dont understand why.
Then I followed the steps but the cast button added with the advice of the guide still remain greyed out like this picture.
Be patient but I'm still learning this kind of things. Thank you