Class CompletionHandler

Get the state of the text editor at the given position.

Handle a completion selected signal from the completion widget.

Handle invoke-request messages.

Handle selection changed signal from an editor.

Notes

If a sub-class reimplements this method, then that class must either call its super method or it must take responsibility for adding and removing the completer completable class to the editor host node.

Despite the fact that the editor widget adds a class whenever there is a primary selection, this method checks independently for two reasons:

1. The editor widget connects to the same signal to add that class, so there is no guarantee that the class will be added before this method is invoked so simply checking for the CSS class's existence is not an option. Secondarily, checking the editor state should be faster than querying the DOM in either case.
2. Because this method adds a class that indicates whether completer functionality ought to be enabled, relying on the behavior of the jp-mod-has-primary-selection to filter out any editors that have a selection means the semantic meaning of jp-mod-completer-enabled is obscured because there may be cases where the enabled class is added even though the completer is not available.

Handle a text changed signal from an editor.

Handle a visibility change signal from a completer widget.