koobas.hobune.stream
Sorting the children of a Grid Layout in 4.6 UI
Hi. So I'm making a quest log. Once I quest is started, I need to add it to the active section of the quest log, which is a Grid Layout. The only problem is, this adds it at the bottom of the list. I want it to be added to the top so the most recent quests appear first. How can I arrange the elements of the grid layout through script? Thanks.
There's a solution that's better performant than de-parenting the UI elements and then parenting them again in the required order, which is using the SetSibling methods from the Transform.
SetAsFirstSibling: Move the transform to the start of the local transform list. SetAsLastSibling: Move the transform to the end of the local transform list. SetSiblingIndex: Sets the sibling index. https://docs.unity3d.com/ScriptReference/Transform.html
So, in your case, when a quest becomes active you just need to set that quest object as the first sibling. You can find more info in this thread: https://forum.unity.com/threads/order-of-elements-in-layout-groups.267668/
This should be the answer. You can make a sorting worker function with these to get the desired behavior.
You need to de-parent your ui elements, sort them (in a List or Array) and then re-parent them to the GridLayout transform in the sorted order. Remember that for UI elements you need to use Transform.SetParent to set the parenting.
This is a good solution, but there's some set sibling methods that performs better and will avoid to lose some FPS. Please, check my answer below.
It depends on what the object holding the list of quests is, but if it's just a plain List why not simply use list.Insert(0, item) when you add it to put it first?
