Maintenance script: UI Lua API import (WAR 1.4.8)

2026-10-16T19:51:13Z

UI Lua API import (WAR 1.4.8)

New page

{{LuaApi|group=Scrollbar}}
Meant to set the line size of a VerticalScrollbar. In the current client it sets the '''page size''' instead. See [[#Details|Details]].

<pre>
VerticalScrollbarSetLineSize(scrollbarName, size)
</pre>

== Arguments ==
;scrollbarName : <code>string</code> – Name of the VerticalScrollbar.
;size : <code>number</code> – The value to store.

== Returns ==
Nothing.

== Details ==
* The client passes the arguments to the scrollbar in the wrong order:
** <code>size</code> becomes the page size (returned by [[API:VerticalScrollbarGetPageSize|VerticalScrollbarGetPageSize]]).
** The line size is set to the page size the scrollbar had before the call.
** If <code>size</code> is larger than the maximum scroll position, the maximum is raised to <code>size</code>.
* To set the line size, use [[API:VerticalScrollbarSetPageSize|VerticalScrollbarSetPageSize]], which has the opposite mix-up. See that page for a call order that sets both values.
* The thumb is recalculated and the current position is clamped again. If that moves the position, the <code>OnScrollPosChanged</code> handler runs.
* The stock UI never calls this function.
* The function needs at least two arguments and only reads the last two. Any extra arguments placed in front of them are ignored.

== Errors ==
* <code>Error in function call 'VerticalScrollbarSetLineSize': Window %s does not exist</code>
* <code>Error in function call 'VerticalScrollbarSetLineSize': Window %s is not a VerticalScrollbar</code>

== Example ==
See [[API:VerticalScrollbarSetPageSize#Details|VerticalScrollbarSetPageSize]].

== See also ==
* [[API:VerticalScrollbarGetLineSize|VerticalScrollbarGetLineSize]]
* [[API:VerticalScrollbarSetPageSize|VerticalScrollbarSetPageSize]]
* [[API:VerticalScrollbarGetPageSize|VerticalScrollbarGetPageSize]]

API:VerticalScrollbarSetLineSize - Revision history

Maintenance script: UI Lua API import (WAR 1.4.8)