AUI

Appearance

The logic half ​

Every view is one C# class split across two files. Name.g.cs is generated from the markup and rewritten on every save; Name.cs is scaffolded once and is yours forever. They are partial halves of the same class, in namespace Armagan.AUI.Generated.

csharp
namespace Armagan.AUI.Generated
{
    public partial class Shop : AuiView
    {
        // your fields, your handlers, your overrides
    }
}

What the generated half gives you ​

For markup like this:

aui
<view name="Shop" width="440" height="360">
  <text key="shop.title" class="title"/>
  <text key="shop.owned" args="{count}"/>
  <slider bind="{volume}" min="0" max="100" onchange="VolumeChanged"/>
  <button id="buy" onclick="Buy" key="shop.buy" disabled="{soldOut}"/>
</view>

you get:

csharp
public const int E_BUY = 7;      // element index, for SetText / AddClass / ...
public const int S_BUY = 2;      // signal id, for SetEnabled / IsSelected

public string Count    { get; set; }   // repaints the text that uses it
public float  Volume   { get; set; }   // moves the slider, no handler fired
public bool   SoldOut  { get; set; }   // enables/disables the button

and it calls Buy() and VolumeChanged(float value) on you.

The full list of what gets emitted, section by section, is in generated code.

The rules that follow ​

A binding becomes a PascalCase property. {playerName} gives PlayerName. Setting it from code updates every element that uses it and does not call your handler. A player moving the control does both.

A handler becomes a method you must write. Its signature is fixed by where it is used, and the scaffolder writes the empty stub for you. If you change the markup so a signature changes, fix the method: the project will not compile until you do, and the queue does not run while it does not compile. See handlers.

Names can collide. A binding whose PascalCase name matches a member of AuiView is an error telling you to pick another name. Also do not declare a field called _<binding>; the generated backing field owns that name.

Lifecycle hooks ​

Override these rather than using Start:

csharp
protected override void OnStart()        { }  // once, after wiring and initial binding values
protected override void OnRetranslate()  { }  // after a language change, once texts have repainted
protected override void OnShown()        { }  // after Show()
protected override void OnHidden()       { }  // after Hide()

OnStart is the important one. It runs after the view has built its tables and applied the initial values of every binding, which Start does not guarantee.

OnRetranslate is where you re-apply anything you wrote with SetText by hand, because a language change repaints keyed text and would otherwise overwrite it.

Writing to a view before it starts

Every public entry point starts the view if it has not started yet, so another script may set panel.Volume = 50f in its own Start even if the panel is on a hidden page. You do not need to sequence them.

A worked example ​

csharp
using UnityEngine;
using VRC.SDKBase;
using Armagan.AUI;

namespace Armagan.AUI.Generated
{
    public partial class Shop : AuiView
    {
        public ShopInventory inventory;   // a normal reference to your own script

        private int _owned;

        protected override void OnStart()
        {
            _owned = 0;
            Refresh();
        }

        public void Buy()
        {
            if (inventory == null || !inventory.TryBuy()) return;
            _owned++;
            Refresh();
        }

        public void VolumeChanged(float value)
        {
            if (inventory != null) inventory.SetVolume(value);
        }

        private void Refresh()
        {
            Count   = _owned.ToString();
            SoldOut = _owned >= 5;
        }
    }
}

Two things worth copying from it: keep your own state in your own fields and push it into bindings in one Refresh method, and null-check every reference to another behaviour, because Udon gives you no exception you would enjoy debugging in-world.

Test methods ​

A parameterless public void _TestSomething() can be sent as a custom event from the editor without entering play mode logic by hand:

csharp
public void _TestJapanese() { if (lang != null) lang.SetLanguageByCode("ja"); }
public void _TestSoldOut()  { SoldOut = true; }

See testing.

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