---
title: "DroppyPanelActivation, DroppyKit"
description: "Droppy made the active app while a droplet's own floating panel is up, and the foreground handed back when it closes (DroppyKit 1.15.0)."
canonical: "https://getdroppy.app/docs/droppykit/api/droppy-panel-activation"
last-updated: "2026-09-09"
---

# DroppyPanelActivation

Droppy made the active app while a droplet's own floating panel is up, and the foreground handed back when it closes (DroppyKit 1.15.0).

`@MainActor final class DroppyPanelActivation`

Droppy runs as a background app, and AppKit delivers mouse moves to a non-activating panel of an app that is not active only now and then: a launcher's rows light up late, or not at all, as the pointer sweeps them, and snap into place the moment Droppy's Settings window happens to be the active one. Begin one right after ordering the panel front, finish it right before ordering the panel out:

```
panel.makeKeyAndOrderFront(nil)
activation = DroppyPanelActivation.begin(for: panel, returningTo: previousApp)
// ...
activation?.finish()
panel.orderOut(nil)
```

It is the session Droppy's own launcher used: the panel becomes key and main, Droppy becomes active, any ordinary Droppy window that was behind another app stays behind it, and `finish()` yields the foreground back to `returningTo` unless the user moved into another Droppy window meanwhile. `nil` outside Droppy (the harness, a host older than 1.15.0).

## Initializers

### init(finish:)

`@MainActor init(finish: @escaping @MainActor () -> Void)`

Creates one. Constructed by hosts.

## Type methods

### begin(for:returningTo:)

`@MainActor static func begin(for panel: NSWindow, returningTo application: NSRunningApplication?) -> DroppyPanelActivation?`

Makes Droppy the active app for `panel`, handing the foreground back to `application` (the app the panel was summoned over) on `finish()`.

## Methods

### finish()

`@MainActor func finish()`

Hands the foreground back. Once; later calls do nothing.