I'm studying only recently Android. I do not know if it's me, but I do not understand the Android sudio documentation regarding the contacts, I tried reading the few guides about it, and other articles, but I could not understand how it works. Now I am only able to read some contacts and their information, but without being able to modify and delete them. My purpose is to create a synchronization of contacts service. The data to whom they are interested are: Name Number (Home, Work, Mobile, Mail). If no one knows how to read the data correctly, edit, delete and create them would be very grateful, perhaps with a sample code. Thank you.
You can get all the information from below link. https://developer.android.com/guide/topics/providers/contacts-provider.html