First iteration of AddSubscriptionScreen cleanup

[ArnyminerZ]

Purpose

Right now AddSubscriptionScreen has a lot of overloads, and complicated LaunchedEffect calls.

Simply too much logic is on the UI. We should move it to the view model, or simplify/remove as needed.

Related to #726

Short description

• Got rid of an overload of AddSubscriptionScreen

Checklist

• The PR has a proper title, description and label.
• I have self-reviewed the PR.
• I have added documentation to complex functions and functions that can be used by other modules.
• I have added reasonable tests or consciously decided to not add tests.

[Copilot]

Pull Request Overview

This PR is the first iteration of cleaning up the AddSubscriptionScreen by removing overloads and moving UI logic to the view model. The main goal is to reduce complexity in the UI layer and better separate concerns.

• Removed one overload of AddSubscriptionScreen and consolidated the logic
• Moved file picking logic and initialization logic from UI to the view model
• Simplified UI state management by removing success handling from the composable

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
AddSubscriptionScreen.kt	Removed overload, simplified LaunchedEffect calls, moved UI logic to view model
AddSubscriptionModel.kt	Added initialize() and onFilePicked() methods, moved Toast handling from UI to view model

Comments suppressed due to low confidence (1)

app/src/main/java/at/bitfire/icsdroid/model/AddSubscriptionModel.kt:1

• The createSubscription() method returns Unit, not a Job or Deferred, so invokeOnCompletion cannot be called on it. This will cause a compilation error.

package at.bitfire.icsdroid.model

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[ArnyminerZ]

Okay, I will take a look at this...

[ArnyminerZ]

Showing Toast messages from the view model violates the separation of concerns principle. UI-related operations like Toast should remain in the UI layer, not in the view model.

I mean, in any case, even though it's now being displayed from the ViewModel, before, the toast was still being triggered from the VM, so it doesn't make any sense...

[ArnyminerZ]

I will ignore copilot.

[sunkup]

Adding local file does not work. After picking file the subscribe button does not show up.

[sunkup]

See comments. Looks good otherwise.

[sunkup]

This seems unnecessarily confusing to me. I am sorry, that I said we could extract it to utils. It does not make sense. I think it's much better to simply trigger and handle cancelation in place when needed. Either in the screens (preferably) or the view model if you think that's much cleaner.