Getting Started

This tutorial will walk you through the creation of a sample application that contains a RadSlider.

Adding Telerik Assemblies Using NuGet

To use RadSlider when working with NuGet packages, install the Telerik.Windows.Controls.for.Wpf.Xaml package. The package name may vary slightly based on the Telerik dlls set - Xaml or NoXaml

Read more about NuGet installation in the Installing UI for WPF from NuGet Package article.

With the 2025 Q1 release, the Telerik UI for WPF has a new licensing mechanism. You can learn more about it here.

Adding Assembly References Manually

If you are not using NuGet packages, you can add a reference to the following assemblies:

• Telerik.Licensing.Runtime
• Telerik.Windows.Controls

Adding RadSlider to the Project

You can add RadSlider in XAML or in code as demonstrated in examples 1 and 2 respectively.

In order to use the RadSlider control, you need to declare the following namespace: xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"

Example 1: Adding RadSlider in XAML

• XAML

<telerik:RadSlider Value="5" Minimum="0" Maximum="100" SmallChange="1" /> 

Example 2: Adding RadSlider in code

• C#
• VB.NET

RadSlider slider = new RadSlider(); 
slider.Maximum = 100; 
slider.Minimum = 0; 
slider.Value = 5; 
slider.SmallChange = 1; 

Dim slider As New RadSlider() 
slider.Maximum = 100 
slider.Minimum = 0 
slider.Value = 5 
slider.SmallChange = 1 

Figure 1: Result from Examples 1 and 2

By default the Value of the RadSlider will be constantly updated while the thumb is dragged. If you want the value to be updated only once, when the thumb is released, you can set the IsDeferredDraggingEnabled property to True.

Setting a Theme

The controls from our suite support different themes. You can see how to apply a theme different than the default one in the Setting a Theme help article.

Changing the theme using implicit styles will affect all controls that have styles defined in the merged resource dictionaries. This is applicable only for the controls in the scope in which the resources are merged.

To change the theme, you can follow the steps below:

• Choose between the themes and add reference to the corresponding theme assembly (ex: Telerik.Windows.Themes.Windows8.dll). You can see the different themes applied in the Theming examples from our WPF Controls Examples application.

• Merge the ResourceDictionaries with the namespace required for the controls that you are using from the theme assembly. For the RadSlider, you will need to merge the following resources:

  • Telerik.Windows.Controls

Example 3 demonstrates how to merge the ResourceDictionaries so that they are applied globally for the entire application.

Example 3: Merge the ResourceDictionaries

• XAML

<Application.Resources> 
    <ResourceDictionary> 
        <ResourceDictionary.MergedDictionaries> 
            <ResourceDictionary Source="/Telerik.Windows.Themes.Windows8;component/Themes/System.Windows.xaml"/> 
            <ResourceDictionary Source="/Telerik.Windows.Themes.Windows8;component/Themes/Telerik.Windows.Controls.xaml"/> 
        </ResourceDictionary.MergedDictionaries> 
    </ResourceDictionary> 
</Application.Resources> 

Alternatively, you can use the theme of the control via the StyleManager.

Figure 1 shows a RadSlider with the Windows8 theme applied.

Figure 1: RadSlider with the Windows8 theme

Telerik UI for WPF Learning Resources

• Telerik UI for WPF Slider Component
• Getting Started with Telerik UI for WPF Components
• Telerik UI for WPF Installation
• Telerik UI for WPF and WinForms Integration
• Telerik UI for WPF Visual Studio Templates
• Setting a Theme with Telerik UI for WPF
• Telerik UI for WPF Virtual Classroom (Training Courses for Registered Users)
• Telerik UI for WPF License Agreement