NativeMonitorInfo

Info

NativeMonitorInfo describes the physical display monitor on which a fullscreen window resides. It extends NativeRect with a primary-monitor flag, giving you both the screen geometry and monitor identity in a single object. This interface is provided by the @eisland/windows-fullscreen-detector package and is returned as part of every FullscreenWindowInfo object.

Interface Introduction

NativeMonitorInfo is a data structure you encounter when working with FullscreenWindowInfo. Every fullscreen window returned by the fullscreen-detector API carries a monitor property of this type, so you can determine which display the window occupies and whether that display is the system's primary monitor.

Usage

You do not create NativeMonitorInfo objects yourself. They are provided as part of the response from the fullscreen-detector functions:

• getFullscreenWindows() returns an array of FullscreenWindowInfo, each containing a monitor field.
• getForegroundFullscreenWindow() returns a single FullscreenWindowInfo (or null), also with a monitor field.
• isAnyFullscreenWindow() returns only a boolean, but the other two functions let you inspect the monitor details.

Typical workflow: call a fullscreen-detection function, then read monitor to learn which display is involved and monitor.isPrimary to branch on primary vs. secondary screens.

Multi-monitor branching

Use isPrimary to apply different logic for primary and secondary displays. For example, you might show notifications only on the primary monitor, or adjust overlay positioning differently on ultrawide secondary screens.

Properties

Property	Type	Description
isPrimary	boolean	true if this monitor is the system's primary display
(inherits)		All properties from NativeRect (left, top, right, bottom, width, height)

Inherited geometry

The left, top, right, bottom, width, and height values describe the monitor's rectangle in the Windows virtual-screen coordinate space. See NativeRect for full details on each field.

Example

TypeScript

import { getFullscreenWindows } from '@eisland/windows-fullscreen-detector';

// Retrieve all currently fullscreen windows
const windows = getFullscreenWindows();

for (const win of windows) {
  // Determine whether the window is on the primary monitor
  const label = win.monitor.isPrimary ? 'primary' : 'secondary';

  // Display the monitor dimensions inherited from NativeRect
  console.log(`"${win.title}" on ${label} monitor (${win.monitor.width}x${win.monitor.height})`);
}

JavaScript

const { getFullscreenWindows } = require('@eisland/windows-fullscreen-detector');

// Retrieve all currently fullscreen windows
const windows = getFullscreenWindows();

for (const win of windows) {
  // Determine whether the window is on the primary monitor
  const label = win.monitor.isPrimary ? 'primary' : 'secondary';

  // Display the monitor dimensions inherited from NativeRect
  console.log(`"${win.title}" on ${label} monitor (${win.monitor.width}x${win.monitor.height})`);
}

Notes

Source of data

NativeMonitorInfo is always populated by the native fullscreen-detector module. You never instantiate it manually. If you need standalone monitor information without a fullscreen window context, use the Windows display APIs exposed by other eIsland plugins.

Coordinate system

The left, top, right, and bottom values use the Windows virtual-screen coordinate space. On multi-monitor setups these values can be negative (e.g. a monitor to the left of the primary). See NativeRect for details.

Checking monitor identity

If you need to compare monitor identity across multiple calls, compare the left/top coordinate pair rather than relying on isPrimary. The primary monitor designation can theoretically change if the user reconfigures their display settings, but the monitor's position in the virtual screen remains stable as long as the physical setup is unchanged.

Danger Avoidance

Do not assume a single monitor

Always handle the possibility that isPrimary is false. Code that blindly assumes the primary monitor will produce wrong layout or incorrect UI positioning when the user has a multi-monitor setup. Branch on isPrimary or check monitor dimensions explicitly before making display decisions.

Stale monitor data

Monitor information is a snapshot captured at the moment the detection function was called. If the user connects or disconnects a display, or changes resolution, the previously returned NativeMonitorInfo becomes stale. Re-query the fullscreen-detection functions whenever you detect a display-change event rather than caching old results indefinitely.