Function activate

activate(listenerId): void
JMap.Event.Form.activate

Activate the listener.

If listener was already activated, do nothing.

If the listener was deactivated, it state is turn to activate and it will be called again when en event is emitted.
Parameters
- listenerId: string
  The listener id
Returns void
Example
```
// activate the listener "my-form-listener"
JMap.Event.Form.activate("my-form-listener")
```