I have the default query widget and my task is to find a way to either find a default action of turning on a layer or create this action and modify the default widget and add it to it.
is there a default "action" that i can add to a trigger that turns on a layer? and if the answer is no, then where exactly in the files is the code that has all the other default actions?
Assuming you are using the dev edition of WAB. In he widget.js file there are some functions you can utilize. postCreate: is used when the widget is initialized upon opening the map. onOpen:. is used when the widget opens. Opening can be done by clicking or by setting it to open by default.