Ignore blank column/field in embedded report with contextual filtering in Power Apps

[Nielf]

I am playing around with the functionality to embed a Power BI report on a form in a Power Apps model-driven app. I am using contextual filters (JSON filter string), so the report is filtered based on fields/columns of the current row/record.

It works well and I am currently using two fields/columns on the form to filter the report.

However, there might be use cases, where one of the fields/columns might be left blank on the form since it is not required. In this case the report doesn't show any data since the filter will show -1, if the column is left blank.

Is there any way to ignore blank fields/columns when filtering the report and avoid the -1 filter? Perhaps using some of the advanced filter options?