I am having an issue determining how to upload a file to a new record. I have a lightning component and Apex class that creates a new record on a custom object.  I need to be able to allow the user to also add a file at the end of their entries.  But everything I see has to do with uploading files to existing records.  I need to be able to upload a file when a user is creating a record.  All help would be appreciated.
Thanks,
P 

Hi! I'm working on an app to publish on AppExchange. The app needs to connect to my app API to retrieve and update information within Salesforce.

I've created my Custom Named Credentials and connected with oAuth2 with my app, and I understand that I'll have to add this to a Package before publishing the app.

My question is: at what moment do I ask the user for the credentials and permission for Salesforce to access my app API? Do I have to create a setup page, show a login popup or something like that (and how?), or when needed (a request to my server is going to be made on APEX...) does Salesforce makes the redirection to my app for the user to login and then goes back to Salesforce website?

I have looked for the information on how this will work but haven't found a clear reference on this process/flow...

Thanks for your help!
 

I am having an issue determining how to upload a file to a new record. I have a lightning component and Apex class that creates a new record on a custom object.  I need to be able to allow the user to also add a file at the end of their entries.  But everything I see has to do with uploading files to existing records.  I need to be able to upload a file when a user is creating a record.  All help would be appreciated.
Thanks,
P