---
title: altIncrementValue
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nsslidercell/altincrementvalue
---

# altIncrementValue

The amount by which the slider changes its value when the user Option-drags the knob.

## Declaration

```swift
var altIncrementValue: Double { get set }
```

## Discussion

Discussion By default, the value of this property is -1.0, and the slider behaves no differently with the Option key down than with it up. If you set this property, the number should correspond to the range of values the slider can represent—for example, if the slider has a minimum value of 5 and a maximum value of 10, the value should be between 0 and 5.

## See Also

### Related Documentation

- [Slider Programming Topics](apple-archive/documentation/Cocoa/Conceptual/Slider.md)

### Managing Cell Behavior

- [prefersTrackingUntilMouseUp](appkit/nsslidercell/preferstrackinguntilmouseup.md)
- [trackRect](appkit/nsslidercell/trackrect.md)