background for photo album

[BKFC]

I'm sure these are elementary questions but I was not able to find answers.

I'm trying to create a photo album as I used to do with Adobe InDesign.  I'd like to be able to edit the album with jpg images placed and re-sized together with some text on top of a white background, then switch to black when editing is complete.  I have two related problems:

1. I had already created another album several months ago that has a black background, but I can find no way to turn it off (then back on).  Also, I discovered that pages were 'locked' (I don't recall doing this, since I don't know what it entails), and that I had to 'unlock' them to do anything.
2. For the present project, I can find no way to set up a layer with a switchable (black) background. 

In both cases, I tried working with A-Master and with individual files.  Nothing worked in either case.

[R C-R]

To begin with, it would help to know which Affinity app you are using. If it is Affinity Publisher, are you placing jpg images in Picture Frames or directly onto pages? Either way, are you placing items on document or Master pages?

[BKFC]

Sorry - I'm using Affinity Publisher on a Mac.  I assume that I'm placing jpg images onto pages (I don't know what picture frames are) with links rather than embedding.  I also assume that I'm placing the images onto the pages, as these form the unique pages of the photo album.  I want the digital equivalent to an old-fashioned paper album where physical photographs are stuck onto black pages, but with the ability to turn off the black background during layout.

I send pdf files to Printique for printing a book.  I've done this many times with InDesign.  To make a new album, I usually make a copy of a previous album that has the correct background settings, then delete all the images and place new ones onto the blank pages.

I was able to download a .imdl template into Affinity Publisher which visibly shows the margins, but now I must put in the background by hand.

[Alfred]

If your pages already have a black background but you want a white background while editing, you could simply cover the page with a white rectangle, arrange the images and text on top, and then hide or delete the white rectangle when you’re finished.

[BKFC]

With Affinity Publisher, I'm starting with a plain template that simply has margins for printing (e.g. bleed areas).  The background is white.  I am unable to generate any kind of background.  From what I can read, I thought one created a layer consisting of a transparent (i.e. the photo images cover it up) black backgroud, and I can turn the layer on and off.  But clearly I'm missing something.

[R C-R]

Picture frames are made with one of the two picture frame tools. There are several ways to place pictures into these frames, & to scale & position them inside the frame. The frames can have their own background fill color or the fill can be set to clear when content is added via the "Clear fill on populate" button.

Documents can be set up to have transparent backgrounds via the Color tab in the Document Setup window. If not set to transparent page backgrounds will show as white. There should not be a black page background unless there is a black layer of some sort creating that, which should be visible in the Layers panel, possibly on a Master page.

[Wosven]

Add the layer in the master page, and hide it there:

BG_example.afpub

[BKFC]

Wosven suggestion worked - thanks very much!