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  "identifier" : "/documentation/AppKit/NSEvent/ButtonMask-swift.struct",
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# NSEvent.ButtonMask

Constants you use to identify the activated tablet buttons in an event.

```
struct ButtonMask
```

## Topics

### Getting the Tablet Button Masks

[`penTip`](/documentation/AppKit/NSEvent/ButtonMask-swift.struct/penTip)

A mask that matches the pen tip.

[`penLowerSide`](/documentation/AppKit/NSEvent/ButtonMask-swift.struct/penLowerSide)

A mask that matches the button on the lower side of the device.

[`penUpperSide`](/documentation/AppKit/NSEvent/ButtonMask-swift.struct/penUpperSide)

A mask that matches the button on the upper side of the device.

### Initializers

[`init(rawValue:)`](/documentation/AppKit/NSEvent/ButtonMask-swift.struct/init(rawValue:))

### Deprecated

[`NSPenLowerSideMask`](/documentation/AppKit/NSPenLowerSideMask)

The button on the lower side of the device is activated.

[`NSPenTipMask`](/documentation/AppKit/NSPenTipMask)

The pen tip is activated.

[`NSPenUpperSideMask`](/documentation/AppKit/NSPenUpperSideMask)

The button on the upper side of the device is activated.


---

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