Variants in Backstage Lite

In lite, treat sequence variants as sheet configuration profiles: different static layouts for the same objects (for example default, mobile, desktop), not separate timelines.

The API names match full Backstage for upgrade compatibility: declareSequenceVariants, setActiveSequenceVariant, getActiveSequenceVariant.

Declaring variants

Call sheet.declareSequenceVariants() once per sheet before relying on non-default variant folders:

const sheet = project.sheet('Hero')

sheet.declareSequenceVariants(['default', 'mobile', 'desktop'])

The "default" variant always exists. In studio-lite, variant rows appear in the outline; each variant has its own static override tree—no per-variant sequence length or playhead.

Full Backstage also stores keyframes per variant in sequencesById. Lite does not author or play those tracks; see Sheet sequence variants for the full feature set.

Switching at runtime

sheet.setActiveSequenceVariant('mobile')

sheet.sequence remains a stub in core-lite—do not call play() for layout switching.

Read the active name with sheet.getActiveSequenceVariant().

Values callbacks

obj.onValuesChange((values, meta) => {
  console.log(meta.variant) // e.g. 'mobile'
})

How static values merge

• Default variant: staticOverrides.byObject.
• Other variants: staticOverridesByVariant[variantId].byObject merged over default when the object is assigned to that variant in Studio.

Studio-lite writes the same historic fields as full Studio for static data. Sequence tracks, if present in JSON from a full export, are ignored at runtime in core-lite.

Sheet-level props

sheet.props() are shared across variants—they are not duplicated per variant folder (same as full Backstage).

Variant list is not in JSON

The list of variant ids is registered in code, not stored in exported state. After deploy, call declareSequenceVariants with the same ids you used during authoring, or Studio preview and runtime resolution will not line up.

API

declareSequenceVariants, setActiveSequenceVariant, getActiveSequenceVariant — signatures match full core; use the lite packages in lite apps.