`RiveViewModel` constructors use `try!` disallowing graceful error handling

[tomekfab]

Description

RiveViewModel constructors use a lot of force try and force unwrapping. Whenever we accidentally provide a wrong state machine name or smth of that sorts our app crash, while without try! we could gracefully handle this.

Provide a Repro

Just init a RiveViewModel with misspelled state machine and you will get:

Thread 1: Fatal error: 'try!' expression unexpectedly raised an error: RiveRuntime.RiveModel.RiveModelError.invalidStateMachine("State machine named xxx not found")

There are errors being thrown that you don't let us handle.

Source .riv/.rev file

not needed

Expected behavior

init throws an error, which we can then handle

Screenshots

Device & Versions (please complete the following information)

• Device: any
• iOS version any

Additional context

https://github.com/rive-app/rive-ios/blob/63bb20eb0a23be4121bfffea30e0d287677d4ac4/Source/RiveViewModel.swift

[dskuza]

Heard! This is definitely an area where the API could be improved. I'd have to see if I can make some change to this without it being breaking (i.e newly marking the init as throws would cause all users to encounter a compiler warning / error).

There is a new API I am working on that will allow for much more graceful error handling across the board, but the timeline on that is still tbd.