Windows

Custom windows are standalone floating panels, separate from the car inspector extension points. Reached via ui.createWindow() / ui.getWindow().

createWindow(identifier, title, builderFunc)

→ WindowHandle

identifier string Unique window identifier

title string

builderFunc (UIPanelBuilder) => void Called each time the window's content is (re)built

Registers a custom window and returns a handle to configure and control it. The window is created resizable at 400×300 by default (300×200 minimum, 1200×800 maximum, centered) — chain WindowHandle methods to change this before calling .show(). Registering the same identifier again replaces the previous definition (a warning is logged).

Throws if builderFunc isn’t a function, or if identifier/title are empty.

var handle = ui.createWindow("my-mod-window", "My Window", buildWindow)
    .size(500, 400)
    .position(WindowPosition.center)

func buildWindow(builder) {
    builder.title("Hello")
    builder.label("This is a custom window.")
}

// Later, e.g. from a command or button handler:
handle.toggle()

getWindow(identifier)

→ WindowHandle?

identifier string

Returns a handle for an already-registered window, or null if no window (custom or built-in) with that identifier exists. Works for built-in windows too, though a handle for one supports only part of WindowHandle.

Registrations don’t survive a map/session change — a custom window must be re-created each time Main.rl runs. There’s no method to unregister a window; re-registering the same identifier is how you redefine one.

WindowHandle

Returned by createWindow()/getWindow(). Configuration methods return the same handle, so calls chain together; they only take effect the next time the window is shown, not on an already-open window (position changes never apply to an already-open window; size/resizable changes apply immediately only if the window is already resizable).

A handle for a built-in window supports only .show(), .close(), .toggle(), .isOpen(), and .identifier; the rest are for custom windows only.

close()

Closes (hides) the window without unregistering it.

fixedSize()

→ WindowHandle

Makes the window a fixed size (not resizable), using its current size.

identifier

string

The window’s identifier, read-only.

isOpen()

→ bool

Returns true if the window is currently shown.

position(position)

→ WindowHandle

position WindowPosition

Sets where the window opens — see WindowPosition.

rebuild()

Deprecated. Use setNeedsRebuild(), or rebuildImmediately() if you need the new content before continuing. Still works the same as rebuildImmediately(), but shows a warning in the in-game message log, once per script.

rebuildImmediately()

Re-invokes the window’s builder function right away to refresh its content, without changing visibility. Does nothing if the window is closed.

resizable(minWidth, minHeight, maxWidth, maxHeight)

→ WindowHandle

minWidth int e.g. 300

minHeight int e.g. 200

maxWidth int e.g. 1200

maxHeight int e.g. 800

Makes the window resizable with the given constraints. All four arguments are required — Relay registers resizable as a fixed four-argument method, so omitting any of them raises an arity error even though the constraints shown above are reasonable values to pass.

setNeedsRebuild()

Rebuilds the window’s content once, later this frame, no matter how many times it is called before then. Does nothing if the window is closed.

setTitle(title)

title string

Updates the window’s title, including on an already-open window.

show()

Shows the window, creating it on first call.

size(width, height)

→ WindowHandle

width int

height int

Sets the window’s default size in pixels.

toggle()

Shows the window if hidden, or closes it if shown.

WindowPosition

Passed to WindowHandle.position().

Value	Description
WindowPosition.center	Centered on screen (the default)
WindowPosition.centerRight	Centered at 75% of screen width
WindowPosition.lowerLeft	Anchored to the lower-left corner
WindowPosition.lowerRight	Anchored to the lower-right corner
WindowPosition.upperLeft	Anchored to the upper-left corner
WindowPosition.upperRight	Anchored to the upper-right corner