---
title: isMainWindow
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nswindow/ismainwindow
---

# isMainWindow

A Boolean value that indicates whether the window is the application’s main window.

## Declaration

```swift
var isMainWindow: Bool { get }
```

## Discussion

Discussion The value of this property is true when the window is the main window for the application; otherwise, false.

## See Also

### Related Documentation

- [isKeyWindow](appkit/nswindow/iskeywindow.md)

### Managing Main Status

- [canBecomeMain](appkit/nswindow/canbecomemain.md)
- [makeMain()](appkit/nswindow/makemain().md)
- [becomeMain()](appkit/nswindow/becomemain().md)
- [resignMain()](appkit/nswindow/resignmain().md)