I am making a shiny app where the user should be able to upload a file then filter the dataset based on the unique values (levels) of all character columns in the uploaded file. I am able to dynamically generate the correct pickerInput (selectInput) elements, but am having trouble executing the filtering. I used the link below as a guide but am having trouble figuring out how to get the selected values (I think input[[paste0("level", .y)]] is where my problem is).