I am using row virtuialization in a grid, with grouping, and on dataload it always starts collapsing all groups. I know I can issue an ExpandAll... but this is extra delay & terrible UI, given that under no circumstance in this use (typical) do I want collapsed groups.
There is a property IsExpanded, but this does not seem to work.
How does one use Row virtualisation, without having to manually expand all groups on each load, and incur the delay involved in a double render?
Greetings from Syncfusion support.
Query: “How to stop Virtualization collapsing all groups?”
We would like to inform that by default when enabling virtualization in DataGrid will show all the grouped columns in collapsed state. This is the default behavior of DataGrid. Because while using virtualization only the current view elements will be rendered. So it is not possible to expand all the grouped records with virtualization. Also we would like to inform that we have lazy loading feature in DataGrid which helps in improving the performance for larger DataGrid. We have documented this in the below UG section. So kindly check the documentation for additional information.
If we misunderstood your query or is you still face difficulties then kindly share the below details to proceed further at our end.
Above requested details will be very helpful in validating the reported query at our end and provide solution as early as possible.
It may be the current default behavior, but that's only because someone chose to do it that way. It is possible, because already a call to .ExpandAllGroupAsync() does exactly that, and also because the default behaviour of paging is to do exactly as I have asked. It defaults to expanded. Row Virtualization is no less compatible with expanded groups than paging is, and this is demonstrated by ExpandAllGroupsAsync().
It would be much better if this behaviour was settable, so that, for example if one has a dataset of just 2 or 300 rows, and wants them to display expanded, then this can be done without a double render.
I hope this can be fixed.
We would like to inform that it is impossible to expand all the grouped records at initial rendering. As It leads to performance degradation. So it is not feasible to achieve your requirement at our end
Please let us know if you have any concerns.
I suggest you update the documentation then to add it to the list of features that are incompatible with your implementation of virtualisation.
We have logged an documentation improvement task and this will be reflected in our UG documentation in any our upcoming releases.
Until then we value your patience.