onactivating

Onactivating is a term used in software design to denote a pre-activation hook or event that is invoked during the activation phase of an object, component, or process. In many frameworks, activation is a lifecycle stage during which resources are initialized and the object becomes ready for use.

Typically, an onactivating handler runs before the object becomes active. It can be used to validate prerequisites, allocate resources, initialize state, or perform setup tasks. Depending on the framework, the handler may be cancellable, enabling the activation to be aborted if conditions are not met, or it may return a value indicating readiness.

Distinguishing stages: Activation lifecycles commonly include at least an activating phase and an activated phase. The onactivating callback corresponds to the former, while onActivated or similar events signal completion. Some frameworks use alternatives such as willActivate or beforeActivate.

Usage patterns: Handlers are often registered as listeners or callbacks for an activation event. They may run synchronously or asynchronously. In asynchronous contexts, onactivating may suspend activation until prerequisites finish, or may trigger resource loading in the background and proceed when ready.

Examples of domains: user interface components that require focus or resource loading before becoming interactive; windows or views in desktop or mobile platforms; modular systems that activate features on demand.

Notes: Because onactivating is not universally standardized, its exact behavior depends on the framework. Consult specific documentation for naming conventions, return semantics, and cancellation mechanics.

See also: activation lifecycle, onActivated, willActivate, beforeActivate, activated.