I assume you can somehow deduct which one you need? If so, create 2 variants, 1 preview for Zebra ZPL and 1 for resulting label pdf. Then add 2 details assign the variants to these details. Depending on the context procedure you either show detail variant ZPL or variant PDF. 

hi Erwin, I understand that variants can be used when opening a document and change the screentype, but in this situation switching between id 5 (no preview) and 6 (working pdf preview) doesn’t change the variant. Or am I missing something?

The file name is zpl and the preview name is pdf? Is that correct? Also what does the context procedure for this tabel look like that decided which detail to show?

In this case the both documents (zpl and pdf) are linked to the shipment, the zpl is not readable for the previewer. For the zpl I can generate an additional image/pdf and save it in this record to show it to the user. There is no context procedure which detail to show, both zpl and pdf records should be shown. 

hi Erwin, I understand that variants can be used when opening a document and change the screentype, but in this situation switching between id 5 (no preview) and 6 (working pdf preview) doesn’t change the variant. Or am I missing something?

 

 

As the previewer shows the first available column, I would suggest you create a expression field that you populate with the preview you want to show e.g. in case of PDF the file and in case of ZPL the preview column..   

Put it as the first visible field and it should always show the preview on the right.