New App: Chromium PDF

[arubislander]

@pparent Hi, great work on the app. I was wondering though: Is there a reason you use pixels and not grid units (units.gu()) in your app for the margins etc?

Using grid units makes it so that it should scale properly across all devices.

[pparent]

@arubislander

Thank's for your remarks I will take into account.

[pparent]

I made a new revision (0.1.2) with New branding, back button working, and removing useless permissions for the app.

Except in case of a bug, this should be go to go without other updates in the following days, and possibly until Qt6.

[Vlad Nirky]

@pparent
Why not use the document viewer?
The PDF file displays correctly on my mobile phone:

/home/jll/Téléchargements/4/screenshot20251017_161517413.png

[pparent]

@Vlad-Nirky said in New App: Chromium PDF:

Why not use the document viewer?

Cos it's very buggy at least on my vollaphone 22 (and it also was on my previous phones). It does not zoom well: it displays blank screen for several seconds each time you try to change zoom, and on top of that position gets lost when zooming.

Also the top menu keeps appearing and disappearing when scrolling vertically, making the display very unstable (sometimes it oscillates at rapid pace)

See:

https://gitlab.com/ubports/development/apps/lomiri-docviewer-app/-/issues/45
https://gitlab.com/ubports/development/apps/lomiri-docviewer-app/-/issues/71
https://gitlab.com/ubports/development/apps/lomiri-docviewer-app/-/issues/72

[Vlad Nirky]

@pparent
Ah, OK...
I hadn't really noticed this issue, the white flashes are quite short and I haven't encountered any scrolling issues on the Xiaomi Redmi Note 9 Pro.
I understand the approach better now, thank you.

[pparent]

@Vlad-Nirky

For me (on Volla phone 22) the flashes are not quite short especially when zooming a lot into the PDF.

I use PDF reading mainly for tickets (train, events, concerts) with a small QR-code inside the pdf, and I have to zoom on the QR-Code to display it fullscreen as fast as possible. With document viewer it take ages to do that.

[Vlad Nirky]

@pparent
Perhaps could you add CI in the app folder.

.gitlab-ci.yml

arm64:
stage: build
artifacts:
expire_in: 1 week
paths:
- build//app/.click
image: clickable/ci-ut24.04-1.x-amd64
script:
- clickable build
armhf:
stage: build
artifacts:
expire_in: 1 week
paths:
- build//app/.click
image: clickable/ci-ut24.04-1.x-armhf
script:
- clickable build

[domubpkm]

@pparent Hi. Thanks for your app. I have a volla 22 like you. It is a good phone with Noble but currently we have the same little problem as with focal : laggy, jerky scrolling in some cases. : https://forums.ubports.com/post/85827 . Do you think it is possible to improve scrolling a little in your app ? Thanks

[pparent]

@domubpkm

In Chromium PDF the zooming & scrolling is mostly fine and quite responsive, much better than document viewer.

Although I think performance will still improve with Qt6 to be perfectly fluid, and with Qt6 PDF.js might be even better than Chromium PDF, and we'll get top-notch PDF reader.

[domubpkm]

@pparent Your app is very good and the improvement was made by volla 22 itself: I am now on dev 486 and scrolling on volla has improved considerably.