I was working on an existing report, and I was trying to preview the report and choose the data adapter, but I do not get any options to choose one. It just says -- No Data Adapter --. And if I click on the down arrow for options, my only option is "Don't use a Data Adapter". I have several data sources setup on my local Studio which work fine when I create a new report. However once I've posted it on the server and then recall it to view, I have the same problem.
Using TIBCO Jaspersoft® Studio Professional 7.5.0 - Visual Designer for JasperReports 6.11.0. on a Mac.
I was having what I think was the same issue and I fixed it by exporting the existing Data Adapter that wasn't showing up, then deleting it from my Data Adapters then importing the one I had exported earlier. I don't think I needed to delete the original, I probably could have just exported then imported and left the original, but I figured I'd just say exactly what I did to get it to work.