Hello @Prarthana
Unfortunately, there is no easy solution for this task, as there is no built-in support for the datatable-like loading (the suggested backend examples do not support it as well).
The dynamic loading in the File Manager assumes getting data folder by folder, once the user selects it.
However, I must admit that an example with 3500 items in folder should not critically affect the client-side performance, as table oe in the right side still use the “lazy rendering” strategy for rows, and there is no “heavy” operations performed on data during loading.
The inner units (tree, dataview, datatable) always address the methods of the Local service, which manages all client-side operations and communicates with Backend service to make necessary data requests and process the results. In short, components get already fetched data with the help of the parse method, while all data management is up to services.
In theory, the deep customization of current logic could make it possible.
This snippet shows the local implementation for dynamic loading. Instead of standalone operations, a similar proxy object can refer to custom methods of mentioned services and obtain data by chunks using “regular” API of datatable and dataview.
But note that since the Local service reloads data in the right side during navigation (clearAll resets all, including the proxy), this proxy should be redefined during navigation.
Also, most probably you’ll need to modify the Cache (the inner service available after init as $$("fm").getService("local").fscache) to not conflict with custom data loading pattern.
As this use-case was not intended by design and assumes a lot of customizations, unfortunately, we cannot provide any examples, but I hope this information will be helpful.
