iOS App: Behavior of "empty" slide layout

[nikslor]

Describe the bug In the sidebar of the impress part one can choose the layout of the current slide (e.g. title + content, title + two content boxes, etc.). The first layout in the list is the "empty" layout.

This option is irritating and useless in my opinion.

See the screenshot:

I'd expect that this layout option just removes the content frames of the slide (like title/content), but instead it renders the slide "transparent". I really see no use for this option as it is right now.

Let's say I have a bunch of slides and all have a white background - why would the slide become transparent if I choose the "empty" layout? Instead the slide should stay white but just not contain any content frames anymore. I would choose this layout to add a slide that only contains one big picture for example.

I propose the following:

1.) Change the "empty" layout to act as a user would expect: just remove the content frames, but keep the background color 2.) Add a new option (as the last option in the list) that behaves like the current "empty" layout but add an "invisible" icon to it - this way we still have the current option and are backward compatible

See a draft proposal here:

**iPad

• Device: iPad
• OS: iPadOS 14.8
• Version: 21.11.1 (1)

[nikslor]

It seems, that the behavior is different (fixed) in Online:

@tml1024 is this an iOS only issue now?

[nikslor]

Let me also add the back link to my initial issue: https://bugs.documentfoundation.org/show_bug.cgi?id=128453

[tml1024]

If I have an existing slide that for instance contains just a photo, selecting the empty layout for it does not make it look different in any way. Ditto if I have an existing slide with a title and some text boxes on it. Nothing changes if I click the empty layout. This is with a 21.11 build of the app. (But if I select some non-empty layout for the slide with just the photo, its about changes to that, and selecting the empty layout after that does not revert that change, I have to use Undo.

[tml1024]

One thing that is unclear to me is whether you are talking about an existing slide, with some contents already on it, for which you then select the empty layout? Or is this a completely new slide with an empty layout?

[tml1024]

OK, now I understand what the issue is, after comparing to Online. Will start looking for the cause.

[tml1024]

My guess is that the root cause for this must be in the iOS-specific vcl code. Because there shouldn't really be any iOS-specific in the sd or slideshow subdirectories of LO (i.e., Impress), just code specific to tiled rendering and LibreOfficeKit in general.

[tml1024]

My intuition told me that this code in vcl/ios/salios.cxx might be related:

    // If called from idle layout, maContextHolder.get() is NULL, no idea what to do
    if (!maContextHolder.isSet())
        return;

Lo and behold, if I add debugging printout to that early return, it indeed seems that this code is hit for a presentation document with such empty slides. But not for documents without empty slides. Hopefully this will be helpful. Will continue debugging tomorrow.

[tml1024]

Hmm, except that even if I managed to change code elsewhere so that the above code called from "idle layout" never gets called, the bug doesn't go away. So it was a red herring apparently.

[eszkadev]

I can confirm, it happens not only on tablet but also on iPhone in iOS app. But not in Safari on the same phone or in desktop browser (that was tested on linux). So - it's something related to iOS app.

[nikslor]

Still present in 22.05.10 (22.5.202302180032)