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# contentViewController

The main content view controller for the window.

```
var contentViewController: NSViewController? { get set }
```

## Discussion

The value of this property provides the content view of the window. Setting this value removes the existing value of [`contentView`](/documentation/AppKit/NSWindow/contentView) and makes the `contentViewController.view` the main content view for the window. By default, the value of this property is `nil`.

The content view controller controls only the [`contentView`](/documentation/AppKit/NSWindow/contentView) object, and not the title of the window. The window title can easily be bound to the [`contentViewController`](/documentation/AppKit/NSWindow/contentViewController) object using code such as: `[window bind:NSTitleBinding toObject:contentViewController withKeyPath:@"title" options:nil]`. Setting [`contentViewController`](/documentation/AppKit/NSWindow/contentViewController) causes the window to resize based on the current size of the [`contentViewController`](/documentation/AppKit/NSWindow/contentViewController); to restrict the size of the window, use Auto Layout (note that the value of this property is encoded in the NIB). Directly assigning a [`contentView`](/documentation/AppKit/NSWindow/contentView) value clears out the root view controller.

## See Also

[`+  windowWithContentViewController:`](/documentation/AppKit/NSWindow/init(contentViewController:))

Creates a titled window that contains the specified content view controller.


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