[Technical Questions] App Crashes When Trying to Send Email in iOS Simulator

[jennleww]

In what area do you have a technical challenge?

Xcode, Simulator & Previews

Description

I am encountering an issue when attempting to use MFMailComposeViewController in my SwiftUI app running on the iOS Simulator. When trying to present the mail compose view via MailView, the app crashes with the following error messages:
• Found a null pointer in a value of type 'MFMailComposeViewController' (0x1021be0b8). Non-Optional values are not allowed to hold null pointers. (Detected while casting to 'UIViewController' (0x10305ee78))
• Unable to initialize due to + [MFMailComposeViewController canSendMail] returns NO.

Since I am running the app on the iOS Simulator, it appears that mail functionality is not available. However, I would like to confirm whether there is a workaround to test this feature in the Simulator or if there is a recommended way to handle this scenario in code to prevent crashes.

Reproduction

Branch: [https://github.com/CS342/2025-CoughSync/tree/ReportShare]

1.	Run the app on the iOS Simulator.
2.	Navigate to the Cough Report screen.
3.	Tap on Share Report → Email Report.
4.	The app attempts to present MFMailComposeViewController, but it crashes with the above error messages.

Expected behavior

I expected the app to present the mail compose view or at least fail gracefully instead of crashing. If the Simulator does not support mail functionality, I would like guidance on how to handle this properly in code.

Additional context

No response

Code of Conduct

• I agree to follow this course's Code of Conduct and Contributing Guidelines

[PSchmiedmayer]

@jennleww There is no workaround for the simulator; you need to use the check if a user can send a mail first and if it returns no you can not instantiate the compose view controller, see e.g.,: https://developer.apple.com/documentation/messageui/mfmailcomposeviewcontroller#Checking-the-availability-of-the-composition-interface

Alternative is to launch the mail app, as we do in: Spezi Contact, but that also won't work in a way that you can test this, you will have to test this on a real device and/or after your PR has been merged and is deployed to TestFlight.