Hi Bernard,
Thanks for contacting Syncfusion support.
Based on your query we suspect that you need to perform filtering in the dataSource at the initial rendering of the Grid. So,
we have attached the documentation of the initial filtering in grid component.
Please refer the documentation to apply the initial filtering to load data based on the initial filtering.
If we mis understood your query then please share the below details to validate further on your requirement.
1. Share more information your requirement that what you want to achieve using the two mentioned variables(Godina and Mjesec) in the onPostDatasource method.
2. Share the Syncfusion package version.
Regards,
Ajith G.