If you need to add some custom code to your App for very special requirements, there are 2 events triggered by the Json API that can be useful.
In order to respond to these events, you can select the events tab of the Widget properties panel,, and then access to the events onJSONdataLoadSuccess and onJSONdataLoadError:
By Selecting an event Handler, the event code will be automatically added to the custom.js file:
Example of code
This event handler implements 3 parameters:
$(this) a reference to $(this) in the current context
Sender a reference to the DOM object (eg. A JSON Repeater)
Data a js object with the loaded data
Example in the Safari Debugger
The Json API Repeaters & Displayers are using the fetch API ( https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API )
If you need to manipulate the options & headers sent to the server, please read this tutorial: https://www.thoriumbuilder.com/tutorial_detail.html?id=162529280
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