# Slider

> Slider is a vanilla slider over a range of numbers with an optional step and custom value text, like the game's FOV and volume sliders.

URL: https://xichil.dev/docs/xis-mvui/v1/widgets/slider/ · Updated: 2026-11-06 · Applies to: Fabric, Quilt, Legacy Fabric, Forge, NeoForge, MC 1.7.10 - 26.3

A vanilla slider over a range of numbers, showing "label: value" on the slider itself, like vanilla's FOV or
volume sliders. The player drags the knob, clicks the track, or uses the arrow keys while it is focused.

```java
// Whole numbers: step 1, cast in onChange
Slider.builder("renderDistance")
        .label(Text.translatable("mymod.distance", "Distance"))
        .range(2, 32).step(1)
        .value(() -> config.distance)
        .onChange(v -> config.distance = (int) v)
        .build();

// A fraction shown as a percentage
Slider.builder("opacity")
        .label(Text.translatable("mymod.opacity", "Opacity"))
        .range(0, 1).step(0.05)
        .value(() -> config.opacity)
        .valueText(v -> Text.literal(Math.round(v * 100) + "%"))
        .onChange(v -> config.opacity = v)
        .build();
```

## Builder

| Method | Required | Default | Notes |
| --- | --- | --- | --- |
| `label(Supplier<Text>)` / `label(Text)` | yes | | the text before ": value" |
| `range(double min, double max)` | yes | | both ends inclusive; `min` must be less than `max`, both finite |
| `value(DoubleSupplier)` | yes | | your current value; re-read on every refresh and during drags |
| `onChange(DoubleConsumer)` | yes | | stores a new value; main thread |
| `step(double)` | no | `0`: any value | the distance between values: `1` for whole numbers, `0.1` for one decimal. At most `max - min`. |
| `valueText(DoubleFunction<Text>)` | no | the number | how the value is shown after "label: " |
| `enabled`, `tooltip`, `visible` | no | | [options every widget has](https://xichil.dev/docs/xis-mvui/v1/widgets/index.md#options-every-widget-has) |

`build()` throws if a required field is missing, the range is empty or infinite, or the step is negative or
larger than the range.

## Behaviour

- Values are `double`s in `[min, max]`. With a step they are `min + k * step`; if the step doesn't divide the
  range, the highest value is the last step below `max`.
- `onChange` runs for **every distinct snapped value while the player drags**, not only on release, and only when
  the value changes. Keep it fast; save to disk from the screen's Done button.
- A `value` outside the range shows clamped.
- An arrow key moves the value by one step, or by 1% of the range without a step.
- The default text has as many decimals as the step (none for whole steps, two without a step), so `12` or
  `0.25`. Use `valueText` for units or names:
  `v -> Text.literal((int) v + " chunks")`, or
  `v -> v == 0 ? Text.translatable("mymod.off", "Off") : Text.literal(String.valueOf((int) v))`.
- Steps such as `0.1` give exact values (0.3, not 0.30000000000000004).
- **Footer:** no.

## Test it

```java
host.slide("renderDistance", 12);      // snapped and clamped as a drag would be
```

Rendered as `[slider renderDistance] Distance: 12`.

## See also

- Javadoc: [Slider](https://xichil.dev/javadoc/xis-mvui/v1/dev/xichil/mvui/Slider.html)
- [NumberField](https://xichil.dev/docs/xis-mvui/v1/widgets/number-field/index.md): for a number the player types exactly.