useImportedModule

When a module composes child modules via imports, the UI often needs to read/dispatch the child module within the parent instance scope (e.g. Query, sub-forms, sub-features).

useImportedModule(parent, childModule) solves this: it resolves childModule from the imports scope of the parent instance and returns a ModuleRef that you can pass directly to useSelector / useDispatch.

Usage

import { useImportedModule, useModule, useSelector } from '@logixjs/react'
import { HostImpl, ChildModule } from './modules'

function Page() {
  // For multi-instance scenarios (session/tab/sharding), use key to distinguish parent instances
  const host = useModule(HostImpl, { key: 'SessionA' })

  // Resolve the child module under the host instance scope (won't mix across host instances)
  const child = useImportedModule(host, ChildModule.tag)

  const value = useSelector(child, (s) => s.value)
  return <div>{value}</div>
}

You can also use the chained sugar (recommended):

const child = host.imports.get(ChildModule.tag)

Notes

• parent must be a handle with “instance scope semantics” (e.g. the return value of useModule(HostImpl, { key }), useModule(HostImpl), or useLocalModule(...)). Do not use useModule(HostModule) (global singleton semantics) as parent when resolving imports.
• host.imports.get(ChildModule.tag) returns a stable ModuleRef, safe to use directly in render (no useMemo needed).

Best Practices

• Prefer UI depends on the Host only: if you only need to “trigger/orchestrate” child behavior, do it inside Host Logic via $.use(ChildModule) (or Link/Process), then expose needed state/actions at the Host boundary.
• When UI must connect to child modules: only when UI must render child state directly, or pass the child module ref down as props, use useImportedModule / host.imports.get(...).
• Multi-level imports: you can chain host.imports.get(A).imports.get(B), but prefer resolving once at the boundary and passing the ModuleRef down to avoid deep components “climbing the tree” everywhere.

See Also

• API: ModuleScope
• Advanced: Composability map