[4.0.1.45][XA2] Visible framedrops when switching tabs in new Settings UI

Bug Reports
,
#1

REPRODUCIBILITY (% or how often): Every Time
BUILD ID = OS VERSION (Settings > About product): 4.0.1.45
HARDWARE (Jolla1, Tablet, XA2,…): XA2
UI LANGUAGE: English
REGRESSION: (compared to previous public release: Yes, No, ?): Yes

DESCRIPTION:

New Setting UI has visible frame drops when switching between tabs

PRECONDITIONS:

STEPS TO REPRODUCE:

  1. Open Settings App
  2. Wait until the System tab loads
  3. Swipe left or right and notice the framedrops when content gets loaded

EXPECTED RESULT:

No frame drops during switching tabs like in People app

ACTUAL RESULT:

Frame drop happens when switching tabs in Settings Apps and the transition is shuttering and sometimes frames went less than 40 frames too.

ADDITIONAL INFORMATION:

Captured the frame drops in a video.
https://drive.google.com/file/d/13hr9dIfGUaOW0yX3D_j_zmNHmasFEOqo/view?usp=sharing

4 Likes
#2

Hi,
No problem on my XA2 Plus Dual Sim. When I swipe left or right I’ve got the waiting circle, no frame drops.

#3

Qt Quick is not very good at loading substantial UI blocks during transitions. There is asynchronous loading support, but it is not really asyncronous but splits the loading in piecewise synchronous steps. Some of the steps may take more than 16ms to construct, which results in frame drops during gesture and following slide in transition. We try to load thing at right movements for user not to notice, but it is a tricky balancing act. We used animator-based transition earlier to help the slide in transition (but does not help gesture), but there were instability issues so the improvement was reverted.

Definitely area to improve in the future. :+1:

10 Likes
#4

Would something like a short delay help?

That’s what I ended up doing in my own App sRadio when it created a heavy component, switch to view- small (think it was around 200ms) delay then create the child components.

I think from a user experience point of view a quick flash of a Busy Indicator followed by fading the view in would be more visually appealing than a very noticeable stutter.

1 Like
#5

In 4.20.19, I think the logic on how the tabs have been loaded has been changed and now all the tabs seem to get loaded when the Settings app is opened(with a few ms of unresponsiveness in the main tab).

Frame drops seem to be almost non-existent in 4.20.19 when switching between tabs.

2 Likes
#6

Settings indeed works fine, although in the Phone application there is still quite a bit of lag when swiping to the People tab if it’s the first time opening it after a reboot. The dialer tab also has a tiny bit of lag. I don’t remember if it was worse on 4.1.0.