How to refer property in default datacolelction when writing czml JSON objects?

This may be a trivial question but I didn’t find any clue so far.
I want to let my json objects in czml to refer to some entity in default datacollection, so that I can dynamically change the common properties in a whole before or after the czml is loaded.

I know you can refer to the property in the same collection by{“reference”:“id#property.path”},
but I want to put these referred metadata entity in default datacollection, so that I don’t need to worry if the submitted czml file has those metadata entity.

I saw the dcouments ReferenceProperty - Cesium Documentation
that you can indicate the data collection in codes, then there must be a way to indicate datacollection in json, could someone tell me how to do that?

@Jia_Fang

Welcome to the community! :wave:

While I do not have a ton of experience working with CZML JSON files, I believe that this is possible. In CzmlDataSource.js we have

We also see that simple.czml

is used in our CZML sandcastle demo

Let me know your thoughts on these resources. Given that I have limited experience using CZML JSON files, community input is especially welcomed.

-Sam