[PATCH] GUI Dropdown list breaks on screen resize with scrollbars=false

[elexis]

When you resize the window while being in gamesetup, the color picker dropdown element from #1580 will be messed up sometimes.

In this screenshot I resized from 1280x1024 to something else and back to 1280x1024.

Notice the last three elements are missing.

This seems to be caused by the scrollbar="false" property of that playerColorPicker[n] element.

Reported initially in the second half of comment:10:ticket:3415

[Imarok]

​http://pastebin.com/fytRJjCr seems to fix this.

[elexis]

So it looks like the scrollbar size is taken into account, even if there is no scollbar. In that case there should be a conditional.

[mimo]

When no resize, everything is fine, and even after resizing (see #4304), if we go back and then reenter the gamesetup window, everything is fine. So the code itself, and the way it deals with scrollbars should be ok. And my interpretation is that something is not reset correctly when resizing (possibly the value of the scrollbar property).

And sorry for #4304, i forgot about this one already 1 year old :-)

[Imarok]

The patch I posted seems to have no side effects.

It also fixes, that the dropdown list without scrollbar is mostly too small:

without patch: with patch:

Edit: Added images I forgot

[mimo]

I agree that the patch seems to be the right thing to do: there is no reason to substract the scrollbar size if we don't have one. But what I do not understand is why it worked without the patch when we do not resize? I would have expected that without the fix, the colorPicker would be always truncated. Maybe it was just by chance that it worked, but nonetheless there is something strange here.

[Imarok]

Maybe it worked without resize, because it somehow considers the textsize on init but not on resize. (just guessing ;))

[Imarok]

proper patch

[Imarok]

Remove a comment

[mimo]

while working at it, you could also remove button_width from lines 385 and 388 as not used in that method.

[Imarok]

removed button_width

[elexis]

There is another bug. When resizing the dropdown (especially visible when resizing while the dropdown is opened), it sometimes needs uses twice the height per element, as if it would do some linebreak. It only shows the first 5 colors up to teal. This is the case with and without the patch (but the patch certainly improves the situation a lot).

[elexis]

Remaining bug when resizing the window horizontally. Not that problematic and not related to the proposed code apparently.

[elexis]

Thanks for the patch and review!

Thats the remaining bug I experience when resizing horizontally. The still shows the state when stopping at the right width.

If it's indeed about linebreaks, it might be similar to #3351.

[elexis]

In 18984:

Don't subtract the scrollbar size from GUI dropdowns when there is no scrollbar. Patch by Imarok, reviewed by mimo, refs #3571.
Remove unused button_width.

[elexis]

The remaining bug seems to only occur with window managers that refresh the window while resizing.

[Imarok]

The remaining bug can be reproduced with a window manager that doesn'`t refresh while resizing. The bug just occurs on specific window widths.

[elexis]

temple found a way to reproduce it reliably on r19839 (almost a22):

1. Start multiplayergame and type a long name that would get a linebreak in the middle, for example (ffffffff gggggggg hhhhhhhh)
2. Switch between two resolutions, for example with the fullscreen/windowed mode toggle hotkey alt+enter and 1024x768 and 1920x1280

Images at ​http://imgur.com/a/1Jge8

When setting the size of the observermode playerselection to a relative width, the bug occurs in that dropdown too (see other images in that gallery).

Potential solution:

temple noticed that calling getComputedSize onTick fixes the issue. getComputedSize calls UpdateCachedSize.

The GUI objects/manager should be able to subscribe to SDL_WINDOWEVENT_RESIZED and call UpdateCachedSize and if the size actually changed, SendEvent(GUIM_RESIZED, "resized");