Threading

Dispatch explicitly when the operation touches UI or an SDK with thread-affinity requirements.

Operation	Threading contract
Managed incoming method/message handler	Background entry by default; opt into MauiChannelDispatchers.MainThread
Kotlin callback handler	Background entry by default; use onMainThread = true for UI
Swift callback handler	Background entry by default; use onMainThread: true for UI
Swift async handler	Runs in a Task; use MainActor.run for UI work
Native view creation, attach, disconnect, reconnect	UI thread required
Event consumption	Dispatch UI updates explicitly from the consumer

Handler entry and completion

Managed incoming handlers enter through a background dispatcher. FIFO entry is preserved for sequential requests; asynchronous completion can occur in any order. No serial queue is held while awaiting a remote response. Reentrant native → managed → native requests are supported.

Set MethodChannelOptions.HandlerDispatcher = MauiChannelDispatchers.MainThread for a managed UI handler. Kotlin setHandler(onMainThread = true) and Swift setHandler(onMainThread: true, handler:) enter native handlers on their main thread. Swift setAsyncHandler uses a background Task; use MainActor.run inside that handler for UI work. A handler must not synchronously block waiting for a remote call. Cancellation callbacks should be short and must not throw.

Native callbacks retain their peers until completion. Session disposal detaches handlers, cancels pending requests, and waits for queued native handler entries before releasing the managed receiver peer. The protocol does not promise to stop an SDK operation that ignores cooperative cancellation.

Native views

PlatformChannelView owns a separate native session for each connection. View creation, attachment, disconnection, and reconnection require the UI thread. Configure options.ViewFactories explicitly; reconnect creates a new instance and invalidates the old channel. See native views.