Idea: Event Listener on Summary Data changed
We have customers using PictureThis to visualize tweets. They use it on a live datasource with frequently changing data. When you hit refresh in Tableau new data is loaded in the sheet which PictureThis is using. But there is no event listener who knows that the summary data is changed and the extensions should update. A workaround is to select a mark and deselect it again. This triggers the extension to update. But it would be better to have a summary data changed event listener.
Example:

Hi merlijnbuit,
I'm new to tableau extensions development, i don't know if there is an existing function for data change event but here is a workaround :
- create a time interval event and check if the data has been changed
`
var refreshTimer = setInterval(refreshDataSource(datasource), 20 * 1000);
function refreshDataSource (dataSource) { dataSource.refreshAsync().then(function () { console.log(dataSource.name + ': Refreshed Successfully'); }); }`
this will automatically refresh your data each 20 seconds.
I am aware that you can set a timeout like that, if I can avoid it i dont want to getSummaryData in a loop and put unnecessary load on Tableau. Instead it would be nice if Tableau notifies us when the summarydata gets updated or changed.
Blargh, yeah we should have this. I have added it to our backlog. Thanks for the good idea!
+1 for this idea!
I have a different use case that would benefit from this feature. I'm using 2020.2's new set control as a "soft" filter via calculated fields. Since changes to the set selection are not a true filter action, they don't trigger a FilterChanged event. Having a SummaryDataChanged and/or a SetChanged event would be great.
Any updates on this issue?
Hi @merlijnbuit Unfortunately, no update, but I'll make sure it is moved up on our request list. John
@merlijnbuit - Just wanted to confirm that @Kovner just moved it up on the team's priority list. Thanks for your input.