[PATCH] GUI List should focus selected element on selectionchange

[elexis]

If one watches a replay from the replay menu and returns to that screen, the previously selected element will be selected again in the replay list. However the element isn't focused, so the user will have to scroll to find the selection.

[wraitii]

Edit: nevermind, segfault. Changing to "if (!scrollbar

selected >= (int)m_ItemsYPositions.size())" the check above fixes it, not sure if it's a good idea.

[elexis]

That's what I thought, but nope:

Thread 1 "pyrogenesis" received signal SIGSEGV, Segmentation fault.
0x00000000008864e5 in CList::UpdateAutoScroll (this=this@entry=0x1cca7c0) at ../../../source/gui/CList.cpp:500
500		if (m_ItemsYPositions[selected] < scroll)

which occurs in the gamesetup when something out of bounds is selected.

[elexis]

In 18935:

Scroll to the selected element after the selection changes. Fixes #4254, refs #3742.

[elexis]

In 20958:

Implement an auto-scroll setting for GUI lists.

Patch By: fpre / ffffffff
Fixes #4987, refs #4254

This allows the replay menu and lobby to focus the selected element if, but only if it is expected by the user.
Replaces rP18935 which scrolled the selected player into view every single time a new playerlist was received by the lobby server.