Hi, I have a KMP project that uses SKIE to map the...

# touchlab-tools

[Flavio Suardi]

Hi, I have a KMP project that uses SKIE to map the Flows defined and used in classes from the shared module into Swift.
In the shared module, I define interfaces that need to be implemented natively. A typical use case is defining an interface for a BLE service, where I want the implementation to be platform-specific.

While everything works smoothly on Android, I’ve run into some limitations when using Flow on iOS.

Let’s say we have the following interface:

interface IBleService {
     val connectionState: Flow<ConnectionState>
     fun scan(): Flow<Device>
}

When implementing this interface in the iOS project, there’s currently no way to create a SkieSwiftStateFlow (or similar) that can be returned from the connectionState property and the scan() function.

Just like on Android, it would be great to have a mechanism to create flows, something like flow {} or channelFlow {} , or even a proper constructor to instantiate them directly.

The question is essentially related to this discussion: https://github.com/touchlab/SKIE/discussions/54, which unfortunately has not been followed up.

Thank you.

[streetsofboston]

Usually, the common code will provide the UI with flows to subsribe to, and hardly ever the UI will provide the common code with flows (the other way around).

Is there a way to replace these Flows with a class that has a method that the iOS UI can call repeatedly instead?

[Flavio Suardi]

Thank you for your reply.
I didn’t fully understand your point. In our case, the interface is not meant to update the UI, but rather to provide a way to implement native business logic behaviors (like ble utils).

We’re thinking about solving this by defining a shared service that implement the interface so that we can still use Flows. The shared service would then rely on native methods that respond to events using a delegation pattern.