topic Re: persist properties without reloading? in Custom Visuals Development Discussion

persist properties without reloading?

jprdynamicapps — Thu, 01 Apr 2021 18:12:02 GMT

Hi,

I'd like to persist the scroll position of my visual. However, when I call persistProperties, I get called back with an update and therefore reload my data, which isn't practical. Any way to keep this from happening or some other way to persist the information?

1. Tried doing it on destroy(), but that doesn't seem to get called.

2. Can't use localstorage because I can't get the visual certified.

3. Maybe some way to recognize that the data hasn't changed? I may resort to a checksum if no better way.

Thanks.

-jpr

Re: persist properties without reloading?

dm-p — Fri, 02 Apr 2021 06:13:19 GMT

Hi @jprdynamicapps,

If you want to use persistProperties, you can't avoid an update being called, as the properties need to be re-enumerated. However, you can check options.type in your update method to determine the kind of operation being carried out and route your logic accordingly.

If it's VisualUpdateType.All or VisualUpdateType.Data, then this indicates the dataView should be re-checked. Otherwise, you should be able to leave it unprocessed. Here's an example of how you might handle this using one of my visuals, if you want to take a look.

It's been a while since I've looked at this in detail, but IIRC manually changing a property in the pane will definitely flag a change in a visual's dataView, but persistProperties might not. If it does, then your idea of a checksum may be how to proceed for subsequent updates, if/when they fire.

Hopefully this provides you with some ideas. Good luck!

Daniel

Re: persist properties without reloading?

jprdynamicapps — Fri, 02 Apr 2021 18:52:23 GMT

Thanks, Daniel. The update type comes back as data, so no joy on that one.

Doing a hash on the matrix part of the dataview is doing the trick for now.

Appreciate your thoughts and your source code.

-jpr