Target selectors feature specification

Transaction specification

Transactions may receive target selectors.

selector APIs

All add\/remove APIs may be provided with a TargetSelector instead of a direct target.

Example pseudo-code:

# Associate a named plan with a target.
runtime.addPlan(plan, to: TargetSelector("#contextView"))

# Remove a named plan from a target.
runtime.removePlan(named: name, from: TargetSelector("#contextView"))

Runtime specification

Support committing plans to targets using target selectors.

A target selector is a string that uniquely identifies one or more targets.

Examples:

• #contextView: The context view for a transition.
• Grid Photo: All Photo children contained within a Grid.

Registration API

Provide an API for associating names with targets.

This API is the mechanism by which the selector tree is defined.

func associateNameWithTarget(name, target)

Lookup API

Provide an API for looking up targets with a given selector.

This API is meant to be used by the commit implementation to resolve specific targets when provided with a target selector.

func targetsForSelector(selector) -> [Targets]