> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/gum/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/gum/code/controls/slider.md).

# Slider

## Introduction

The Slider control provides a way for the user to change a value by dragging the slider *thumb*.

## Code Example: Creating a Slider

The following code creates a Slider which allows the user to select a value between 0 and 30, inclusive. The `IsSnapToTickEnabled` property results in the value being snapped to the `TickFrequency` value. In this case, the value is used to force whole numbers.

```csharp
// Initialize
var label = new Label();
label.AddToRoot();
label.X = 50;
label.Y = 24;

var slider = new Slider();
slider.AddToRoot();
slider.X = 50;
slider.Y = 50;
slider.Minimum = 0;
slider.Maximum = 30;
slider.TicksFrequency = 1;
slider.IsSnapToTickEnabled = true;
slider.Width = 250;
slider.ValueChanged += (_, _) => 
    label.Text = $"Value: {slider.Value}";
slider.ValueChangeCompleted += (_, _) => 
    label.Text = $"Finished setting Value: {slider.Value}";
```

[Try on XnaFiddle.NET](https://xnafiddle.net/#snippet=H4sIAAAAAAAAA5WQUWvCMBSF_0oIe1CQ0dXtpaMPm6gI7mWWbYIg0VxsME20STY38b_vJnYaZAz21vPdc85N756OzNBVNLO1gw4VSljBpPgCmtF3VhPJFiBJThR8kLH_brXvZyrQ6wfOC_2stY3YG3rvkpOcokxvUfouIwWHuimbBBGSR35R18BTX6OnF_oJX1y5CmkM2a6B3YgWYrk2gxq2DtTyE4c359nITBTbFNp7-ootJHA0-JucPa-C29L_T7z_hUkHvZKpFSZmLknSx5y05h0yb5Pc627_5xYF7CzGr4IrDcGM7OOew3H0a3tPVxsJ9p9bBngeU2LIgLVCrchfa-nhGwhOLWwOAgAA)

<figure><img src="https://2695663588-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-M_fzQmxQ1VeUFHcoo2c%2Fuploads%2FOEQYTnqBh6WVDOl8Pblk%2F13_22%2030%2010.gif?alt=media&amp;token=07b42855-eb05-498e-b30c-1cbc50d466c9" alt=""><figcaption><p>Slider reporting its value whenever the value changes or when the change completes</p></figcaption></figure>

## Value

Value is a `double` which represents the number displayed by the Slider. This value can change in response to UI events, binding, or explicit setting in code. Value is always between Minimum and Maximum, inclusive.

The following code directly sets Value:

```csharp
// Initialize
slider.Value = 25;
```

Setting a value outside of its bounds forces the value to the bounds. For example, the following code results in a value of 50:

```csharp
// Initialize
slider.Minimum = 0;
slider.Maximum = 50;
slider.Value = 100; // value is set to 50
```

Value can also be changed by changing either Minimum or Maximum:

```csharp
// Initialize
slider.Minimum = 0;
slider.Maximum = 100;

slider.Value = 80;
slider.Maximum = 75; // this sets Value to 75

slider.Value = 20;
slider.Minimum = 25; // this sets Value to 25
```

## Clicking the Track

`IsMoveToPointEnabled` controls what happens when the user clicks the track. It defaults to `false`.

### Stepping with LargeChange

When `IsMoveToPointEnabled` is `false`, each click on the track changes `Value` by `LargeChange` toward the cursor. Holding the button repeats the step until the thumb reaches the cursor.

```csharp
// Initialize
var label = new Label();
label.AddToRoot();
label.X = 50;
label.Y = 24;

var slider = new Slider();
slider.AddToRoot();
slider.X = 50;
slider.Y = 50;
slider.Width = 250;
slider.Minimum = 0;
slider.Maximum = 100;
slider.LargeChange = 10;
slider.ValueChanged += (_, _) =>
    label.Text = $"Value: {slider.Value}";
```

[Try on XnaFiddle.NET](https://xnafiddle.net/#snippet=H4sIAAAAAAAAA12P0QqCMBSGX-UwuiiQMKsbxYuKiMBuSipBiMVGDeYE3SoK3705h412te_7z_5xPmhbb1SBQlkp6iEmmGSYszdFIXrgCji-Ug4xCPqEpL0PR1EujB0vCEnLfVlKx5317NzvMdMYzDTmom2rOSO0snUHA-Zt5_8KrewbLWd_fGJE3ttvXLnTixSq0NqV-GXlxHd0gqsbXd2xuFET_ZIj5somBHLl-8EyhuHFg8sI4pan61yAPt2yKX1J3TAwk4F5HMLH7Wq6KELNF2tmwsF4AQAA)

`LargeChange` defaults to 25 regardless of `Minimum` and `Maximum`. On a slider from 0 to 1, one click jumps the whole range. On a slider from 0 to 1000, one click barely moves the thumb. Set `LargeChange` to fit your range, or set `IsMoveToPointEnabled` to `true`.

### Moving to the Cursor

When `IsMoveToPointEnabled` is `true`, clicking the track moves the thumb to the cursor. The thumb follows the cursor while the button is held. `LargeChange` is not used.

```csharp
// Initialize
var label = new Label();
label.AddToRoot();
label.X = 50;
label.Y = 24;

var slider = new Slider();
slider.AddToRoot();
slider.X = 50;
slider.Y = 50;
slider.Width = 250;
slider.Minimum = 0;
slider.Maximum = 100;
slider.IsMoveToPointEnabled = true;
slider.ValueChanged += (_, _) =>
    label.Text = $"Value: {slider.Value}";
```

[Try on XnaFiddle.NET](https://xnafiddle.net/#snippet=H4sIAAAAAAAAA12QUWvCMBDHv8oR9qAgo1b3UunDJiKCgmxFJxQkkkMDaQJtoqL43XdJiwvmKb_f3f3D5c4WzdxVLLO1wwGTWlrJlbwhy9iZ16D4ARXkoPECS3_v9SelDvb9U4jCfBtjI_dLvR_JE3eE6Ziw1D6tUVJg3cX9BAizrX8J7OQzsePdC2-lsCf_TCxXtEjlKtKx5NdODpNIL5qVOWNh1kZqO9P8oFBQj_-Q_6YNVw6nJ66PVCxdkqRfOfT2A9j3Ifc8mpUa6LR7F3i1lPEWOtMwnME9znq0pQl7_AHKGcQUgwEAAA)

`ValueChanged` is raised as the thumb moves. `ValueChangeCompleted` is raised once when the button is released, so use it for work that should not run every frame, such as saving a setting. `IsSnapToTickEnabled` applies in both modes.


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