KubeJS Integration

Since 2.2.1

LDLib2 exposes its full UI system to KubeJS scripts — no Java or Kotlin required. You can open UIs, build element trees, apply stylesheets, and wire up data bindings entirely from .js files.

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Opening a UI

The primary entry point is the LDLib2UI event group and the LDLib2UIFactory bindings. Three factory types cover the most common triggers:

Event	Factory helper	Use when
LDLib2UI.block(id, handler)	LDLib2UIFactory.openBlockUI(player, pos, id)	Right-clicking a block
LDLib2UI.item(id, handler)	LDLib2UIFactory.openHeldItemUI(player, hand, id)	Right-clicking with an item
LDLib2UI.player(id, handler)	LDLib2UIFactory.openPlayerUI(player, id)	Commands, keybinds, any trigger

Full usage, context fields, and script placement rules are documented on the UI Factory page.

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Building UIs in KubeJS

Inside a LDLib2UI.* handler, all UI classes are available directly by name — no imports needed:

LDLib2UI.block("mymod:example", event => {
    event.modularUI = ModularUI.of(UI.of(
        new UIElement()
            .addClass("panel_bg")
            .addChildren(
                new Label().setText("Hello from KubeJS"),
                new Button().setText("Click me").setOnClick(e => {
                    // server-side logic here
                })
            )
    ), event.player);
});

Browse the available components, textures, and preliminary concepts:

• UIElement & layout — flex/absolute layout, size, padding, margin
• Stylesheet (LSS) — CSS-like styling for all elements
• Data bindings — reactive value wiring
• Components — all built-in elements (Label, Button, ItemSlot, Scene, …)
• Textures — ColorRectTexture, SpriteTexture, SDFRectTexture, …
• XEI integration — JEI / REI / EMI slot and ingredient wiring

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Binding Availability

@KJSBindings marks which classes and methods are exposed. Classes annotated with modId (e.g. @KJSBindings(modId = "jei")) are only available when that mod is loaded. All core UI classes have no mod restriction.