I want to import a PDF-file into InDesign including the layers of the imported PDF.
When I import it, only the file is imported but not the layers.
Layers in placed PDFs are accessed by selecting the placed PDF and choosing Object>Object Layer Options. If the PDF has layers, you should be able to see them in the dialog. You may need to click the arrow to the left of the topmost item to display them. Are you not seeing any layers when doing so?
I'm seeing the layers but when the PDF is imported the layers won't appear in the document file.
Yes, it is. That's how it works - PDF layers is only layers in PDF, not layers in the InDesign. You can only maipulate them
>> using the Object>Object Layers Option function
To add to David's reply, you can also select layers when you Place the file. In the Place dialog, click "Image Import Options" or simply hold Shift as you click on the file to Place. You'll get the PDF import options; click the 2nd tab "Layers" and select the layers you want to import.
PDFs that were originally exported with layers from InDesign for Acrobat will still have their layers recognized when imported back into InDesign using the Object>Object Layers Option function. However, pdfs with layers exported from Photoshop have a different architecture to them and will not keep their layers when opened in InDesign. However, if you first open a layered .PSD in Illustrator and choose the "Convert Layers to Objects" option upon opening and then save the Illustrator file as an Adobe PDF you will find that when you import that pdf into InDesign the layers will appear in the Object Layers Options. You should know, though, that the Object Layers Options allows you to turn the layers off and on but does not provide any other editing of the layers.
ID still can't normally redact imported PDF's. Only can be placed.
Here the feature request about it. Give your voice here - https://indesign.uservoice.com/forums/601021-adobe-indesign-feature-requests/suggestions/30985276-co...