setInvocationHandler method

@override void setInvocationHandler(IntentInvocationHandler handler, { bool background = false, })

Installs the callback the native side routes invocations to.

background selects the isolate this binds to. The headless engine has its own binary messenger, so it needs its own channel — a channel created in one isolate is invisible to the other.

Implementation

@override
void setInvocationHandler(
  IntentInvocationHandler handler, {
  bool background = false,
}) {
  if (background) {
    _backgroundInvocations = handler;
  } else {
    _invocations = handler;
  }
}