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Fluid Capabilities

This article explains the fluid capabilities RadRotator offers. The control supports fluid design since Q2 2014.

Generally, responsive design means that the page and its content are able to adapt to different screen resolutions without deteriorating the user experience. This often includes changing the font size and having dimensions set in percent.

Fluid Design with RadRotator

RadRotator is a control that moves its content dynamically in order to display parts of it in a sequence. The size of the rotator and its items is usually set in pixels according to the instructions in the How to configure RadRotator help article so that the control can calculate how much items will be visible in its view port.

RadRotator supports setting its Width property in percentage as of the Q2 2014 release of UI for ASP.NET AJAX. This means that the control can adapt to the width of the current screen resolution. You can try the responsive capabilities of RadRotator with Example 1.

Example 1: RadRotator with 100% width.

<telerik:RadRotator RenderMode="Lightweight" runat="server" ID="RadRotator1" RotatorType="Buttons" Width="100%" ItemWidth="200px" Height="50px">
        RadRotatorItem <%# Container.DataItem %>
protected void Page_Load(object sender, EventArgs e)
    if (!IsPostBack)
        RadRotator1.DataSource = Enumerable.Range(1, 20);
Protected Sub Page_Load(sender As Object, e As EventArgs)
    If Not IsPostBack Then
        RadRotator1.DataSource = Enumerable.Range(1, 20)
    End If
End Sub

When you set the width of RadRotator in percentage the number of items in its view port cannot be controlled, because the width will change dynamically, however the items' width is fixed. As a result the first and last item in the view port may be partially visible.

If you have set the RotatorType property to Carousel, CarouselButtons, CoverFlow or CoverFlowButtons, changing the screen width will trigger the resizing of the rotator container, however, the position of the items inside will remain the same and part of them may be hidden. You can handle this scenario manually by attaching to an event that is fired when the width of the rotator changes and calling the Client-Side function repaint(). Example 2 shows a possible approach to achieve this.

Example 2: RadRotator is repainted on window resize so that its items are adjusted according to its size.

<script type="text/javascript">
    var rotator = null;
    function OnClientLoad(sender, args) {
        rotator = sender;

    window.onresize = function () {
<telerik:RadRotator RenderMode="Lightweight" runat="server" ID="RadRotator2" RotatorType="CarouselButtons" Width="100%" ItemWidth="200px" Height="450px" 
    OnClientLoad="OnClientLoad" >
        RadRotatorItem <%# Container.DataItem %>

The repaint() functions redraws the entire rotator control. If you call it repeatedly you will most probably encounter performance issues. This is why it is suggested to invoke this function with an interval to achieve as smooth resizing as possible.

See Also

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