Window Migration Guide

How to migrate an existing window from direct BrowserWindow creation to WindowManager.

Step 1: Add the WindowType

In types.ts, add a new enum value:

export enum WindowType {
  // ...
  MyWindow = 'myWindow',
}

Step 2: Register in windowRegistry.ts

Define the window's metadata and default configuration:

WINDOW_TYPE_REGISTRY[WindowType.MyWindow] = {
  type: WindowType.MyWindow,
  lifecycle: 'singleton',       // or 'default' or 'pooled'
  htmlPath: 'my-window.html',
  // preload omitted → defaults to 'preload.js'. Write basename (with extension)
  // to select a different file in src/preload/. Empty string → no preload.
  // preload: 'simplest.js',
  showMode: 'auto',             // 'auto' | 'immediate' | 'manual'
  windowOptions: {
    ...DEFAULT_WINDOW_CONFIG,
    width: 800,
    height: 600,
  },
  behavior: {
    // Declarative WM-level behaviors (all optional). See the README "Configuration Layers" section.
    // hideOnBlur: true,                    // auto-hide on blur (runtime override: wm.behavior.setHideOnBlur)
    // alwaysOnTop: { level: 'floating' },  // level/relativeLevel for setAlwaysOnTop (runtime override: wm.behavior.setAlwaysOnTop)
    // visibleOnAllWorkspaces: { enabled: true, visibleOnFullScreen: true },
    // macShowInDock: false,                // do not contribute to Dock visibility (macOS helper windows only; default true)
    //                                      // runtime override: wm.behavior.setMacShowInDockByType(type, value) for tray-mode transitions
  },
  // quirks: { ... },                       // OS hacks — see Platform Configuration
}

See Lifecycle Modes for choosing between default / singleton / pooled.

Optional: for singleton types that benefit from pre-warm or close→hide, set singletonConfig. See Warmup Mechanics → Singleton Variant.

Step 3: Move domain logic to onWindowCreated

Replace direct new BrowserWindow() + setup code with an onWindowCreated subscription in your domain service:

Before:

class MyService {
  private window: BrowserWindow | null = null

  createWindow() {
    this.window = new BrowserWindow({ width: 800, height: 600, ... })
    this.window.loadFile('my-window.html')
    this.window.on('closed', () => { this.window = null })
  }
}

After:

@Injectable('MyService')
@ServicePhase(Phase.WhenReady)
class MyService extends BaseService {
  private windowId: string | undefined

  protected override onInit(): void {
    const wm = application.get('WindowManager')

    wm.onWindowCreatedByType(WindowType.MyWindow, ({ window, id }) => {
      this.windowId = id
      // attach listeners here — use `window` directly, or switch to the `mw` shorthand
      // if the callback body has inner closures (see Usage Guide → Callback styles).
    })

    wm.onWindowDestroyedByType(WindowType.MyWindow, () => {
      this.windowId = undefined
    })
  }

  openWindow(): void {
    const wm = application.get('WindowManager')
    this.windowId = wm.open(WindowType.MyWindow)
  }
}

See Injecting behavior: onWindowCreated is the canonical hook for the full rationale behind this pattern.

Step 4: Replace direct BrowserWindow references

Note: there is intentionally no entry for this.window.destroy(). wm.close() already handles destruction for non-pooled windows and pool-return for pooled windows. wm.destroy() is an internal primitive — see Window API layers.

Step 5: Handle show behavior

Remove manual show / ready-to-show logic if using showMode: 'auto' (the default). WindowManager handles:

• Creating the window hidden
• Showing on ready-to-show (fresh path) or immediately (recycled path)

If your window needs custom show timing, set showMode: 'manual' in the registry and manage visibility yourself.

Checklist

• Added WindowType enum value in types.ts
• Registered metadata in WINDOW_TYPE_REGISTRY in windowRegistry.ts
• Chose the correct lifecycle mode (default / singleton / pooled)
• Set preload filename if not using the default ('preload.js')
• Set showMode behavior ('auto' / 'immediate' / 'manual')
• Set behavior.macShowInDock: false ONLY for helper windows (floating panels, selection overlays); primary app windows leave it at the default true. Use wm.behavior.setMacShowInDockByType(type, value) for runtime tray-mode transitions, not a different registry default.
• Declared behavior.hideOnBlur / behavior.alwaysOnTop / behavior.visibleOnAllWorkspaces as needed
• Moved domain logic from constructor to onWindowCreated hook
• Replaced direct BrowserWindow references with WindowManager API calls
• Removed manual ready-to-show handling (if using showMode: 'auto')
• If the window consumes init data: replaced hand-rolled getInitData + reset IPC wiring with the useWindowInitData hook
• If pooled: chose appropriate PoolConfig axes (standbySize for active pre-warm, recycleMinSize/recycleMaxSize for recycling). Leave recycleMaxSize unset for one-shot "close destroys" semantics; set standbySize when zero-wait matters under concurrent opens.
• Verified onWindowDestroyed cleanup in the domain service