Bug 423988

Summary:	Single keystroke scrolls more than a screenful
Product:	[Applications] gcompris	Reporter:	Avinash Sonawane <rootkea>
Component:	general	Assignee:	Bruno Coudoin <bruno.coudoin>
Status:	RESOLVED FIXED
Severity:	normal	CC:	animtim
Priority:	NOR
Version First Reported In:	git master
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Avinash Sonawane 2020-07-08 09:37:05 UTC

Hello!

I'm using GCompris 0.97 Based on Qt 5.12.8 on Ubuntu 20.04 LTS.

How to reproduce:
1. Open The tangram puzzle game
2. Click `?`
3. Press down-arrow key once and you'll see that more than a screenful text gets scrolled in one go thereby making it impossible to read the very first line after a screenful as it gets scrolled.

The same can be reproduced by clicking "Down-arrow" icon instead of pressing down-arrow keyboard key.

The same behavior happens with the Configuration settings.

The fix can be restricting the one keystroke scroll to half a screenful. Please note that anything less than a screenful will work. Even one keystroke scrolls exactly a screenful will work too, but we should avoid this as that makes screen to be filled with completely new text leaving user wondering whether they missed any text right after the text on previous screen. Good scrolling unit is such that it scrolls a part of the screen in a single keystroke so that after one keystroke there is still some text from previous screen assuring user that they didn't miss anything.

Thanks!

Comment 1 animtim 2020-07-08 13:54:28 UTC

This seems to be device-dependent, as with the current value one key press scrolls around half-screen here, both on my computers and on my phone (it is the same value that is used when pressing the blue arrow buttons).

I'll make the value half less then, hoping it will be good for you too.

Comment 2 animtim 2020-07-08 14:12:19 UTC

So, I've reduced a bit the flick value, so now it moves of 1/3 of screen height here. I've also hardcoded the flickDeceleration value as else the default is platform-dependent.

Let me know if it works better for you.

Comment 3 Avinash Sonawane 2020-07-08 15:20:50 UTC

(In reply to animtim from comment #1)
> This seems to be device-dependent, as with the current value one key press
> scrolls around half-screen here, both on my computers and on my phone (it is
> the same value that is used when pressing the blue arrow buttons).

If it makes any difference then I use gcompris in windowed mode (no fullscreen) and has xfce panel at the bottom of my laptop screen. Screenshot here: https://i.imgur.com/ByYvJNo.png

> I'll make the value half less then, hoping it will be good for you too.

Thank you! The last commit fixed the issue for me!

Comment 4 animtim 2020-07-08 15:23:54 UTC

Great, thanks for your feedback.