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# canBecomeMain

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

```
var canBecomeMain: Bool { get }
```

## Discussion

The value of this property is <doc://com.apple.documentation/documentation/Swift/true> when the window can become the main window; otherwise, <doc://com.apple.documentation/documentation/Swift/false>.

Attempts to make the window the main window are abandoned if the value of this property is <doc://com.apple.documentation/documentation/Swift/false>. The value of the property is <doc://com.apple.documentation/documentation/Swift/true> if the window is visible, is not an [`NSPanel`](/documentation/AppKit/NSPanel) object, and has a title bar or a resize mechanism. Otherwise, the value is <doc://com.apple.documentation/documentation/Swift/false>.

---

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