I fully agree on points 1 and 2, those should be done.

Actually I'm not even sure this is a good activity concept, as it has the same flaws as the "intro gravity" activity we have. That is:
-increasing the size of something doesn't directly means increasing its mass (if you stretch something, it will take more space but have the same mass), that can lead to bad misconception for kids.
-increasing the size of a planet sounds very weird to me, as it's not realistic at all.

Sorry, actually I this task is a left-over that I forgot to close after fixing the layout of this activity.
The current number of buttons is intended, and increase at each level to introduce new functionalities progressively.
As we don't want to remove features, I'm closing it now.

Sure you're right :) I was not sure if using that kind of #if was allowed inside this context, that's why I defined a variable for it.
We can change like that in master.

Hi,
It is true that the overlapping was not really a problem. But since your change doesn't have any bad side effect I'm ok to get it merged.
Also I'll refactor the graphics and layout of this activity at some point later anyway, so this little patch is good for now.

Yes sure, greying them in the list as "inactive" is what I meant by disable them. Just needs to add a reminder there that those are disabled by the global filter.

@echarruau :
-This "maximun difficulty selected" entry was initially just meant as an info of what is currently selected in the list. Maybe we could also use it as you suggest to auto-select a range of activities, but this should be better handled by the global difficulty filter (the one we already have).
-The only thing that should prevent the user to select a certain difficulty of dataset should be the global difficulty filter (in which case we must display a message to indicate those are disabled by the active filter).

The mock-up is here : https://phabricator.kde.org/M146

-translation done
-voices are coming soon

This patch looks very good! Though +1 that it needs a solid update plan...

Indeed the images on the top are just decorations; also the position of the image is fixed on purpose, making the part under the OK button changing depending on the screen/window size.
So, we don't need to move the ok button at all, this possible overriding is part of the design.

railroad fixed in a0fb2028f924c370de8db104539c8e5ccfac7a42

hanoi fixed in 98d98eb160987f4d2f58973a13c7a1dddac821fb