I have followed many of the questions regarding the errors in the listview sample code and have copy and pasted code from Robert's entries and am still unable to get the sample to work. When I run Web AppBuilder and add the custom widget, I get an error that says: "Create widget setting page error: widgets/ListView/Widget". This error message has an "OK" button which I click and the ListView icon shows up in the placeholder. When I click the icon, I get an error that says: "Create widget error: widgets/ListView/Widget" also with an "OK" button.
I am using Web AppBuilder 2.12 and running in chrome. When viewing the network traffic in developer tools in chrome, I see an error that says "lang is not defined". Is there something I need to install for Web AppBuilder to work with this sample?
I was successful with the "Create a custom in-panel widget" sample code but it does not use lang.