Scaling for UIListLayout's content

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In my experience, using scaling in scrolling frames is generally buggy. What I’ll typically do is keep the amount of scaling on the X-axis but use offset on the Y.

Since scrolling frames typically doesn’t use the X-axis for the CanvasSize property you can set that to 0.

To work around this, everytime I update the items in the scrolling frame, I’ll set the initial size of that frame and set a local variable as a template for each clone.

This is probably better ellaborated in the form of code rather than explained via text, so I’ll give a sort of rough idea of what that’d look like.

Some extra details I should mention is that generally you don’t want to use the “ContentSize” property in ScrollingFrames since that’ll put it into a constant loop of updating the canvas size, especially if you update in a Property Change event. Generally, it’s best you calculate CanvasSize yourself.

It’s somewhat unfortunate that Roblox’s UI engine is so counterintuitive, but you just learn over time to work around the issues.

local yAxisSize -- this will be used for a basepoint for calculating the size
for i, data in ipairs(...) do
	local template = template:Clone()
	template.ListOrder = i
	if yAxisSize then
		template.Scale = yAxisSize
	end
	... -- update the name and properties of the template here
	template.Parent = scrollingFrame -- absolutesize is calculated in roblox's engine, you can now set it

	if not yAxisSize then
		yAxisSize = template.AbsoluteSize -- i opted to just set offset as the absoluteSize to save time but it's up to you whether or not you want to use both scaling and offset
		template.Size = UDim.fromOffset(yAxisSize.X, yAxisSize.Y)
	end

	if yAxisSize then -- this conditional basically makes sure that all this logic was applied before updating the canvasSize
		scrollingFrame.CanvasSize = UDim.fromOffset(0, (yAxisSize.Y * i) + (i * UIListLayout.Padding.Offset)) -- i set the x size to zero since I don't really see a use for sideways scrolling but your milage may differ
		-- i should also mention that i used i - 1 because you shouldn't account for extra padding on the scrollingframe
		-- also, don't use scale for padding as well since many inconsistencies can happen.  a general rule of thumb is that offset is the only thing you should use in scrollingframes (or with UIConstraints in general)
	end

end

Anyway, that’s just my two cents, UI tends to be a pain in the ass and hopefully I can help a lot of people who don’t know all the niche information about it. :slight_smile:

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