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Distorted Appearance

This help article describes what to do when you have an appearance issue with RadToggleButton and provides a resolution.

The appearance of RadToggleButton may be distorted (Figure 1) when the control is declared on the same page that contains a RadButton with a Classic RenderMode (i.e., the default RenderMode).

Figure 1: Distorted appearance of RadToggleButton when placed on the same page with RadButton RenderMode="Classic".

distorted appearance

Example 1: The code that reproduces the appearance issue from Figure 1.

<telerik:RadToggleButton ID="RadToggleButton1" runat="server">
        <telerik:ButtonToggleState Text="ToggleState1">
            <Icon CssClass="rbOk" />
        <telerik:ButtonToggleState Text="ToggleState2">
            <Icon CssClass="rbCancel" />
<br />
<telerik:RadButton RenderMode="Lightweight" ID="RadButton1" runat="server" Text="RadButton" />

Cause of the Problem

Generally, controls from the Telerik® UI for ASP.NET AJAX suite that use the same styles support only a single type of RenderMode per page. This also includes instances from user controls and master pages.

RadButton, RadToggleButton and controls that utilize them, however, share similar resources. Since RadToggleButton supports only a Lightweight RenderMode, its styles may interfere with the styles of the Classic RadButton. The improper appearance is shown in Figure 1 and the code that creates it shown in Example 1.

How to Resolve It

To resolve this issue you should:

There are two ways to configure the rendering mode of the controls:

  • The RenderMode property in the markup or in the code-behind that can be used for a particular instance:


    <telerik:RadButton ID="RadButton1" runat="server" RenderMode="Lightweight">


    RadButton1.RenderMode = Telerik.Web.UI.RenderMode.Lightweight;


    RadButton1.RenderMode = Telerik.Web.UI.RenderMode.Lightweight
  • A global setting in the web.config file that will affect the entire application, unless a concrete value is specified for a given control instance:


        <add key="Telerik.Web.UI.Button.RenderMode" value="lightweight" />
  • Render Modes

  • Client-side Click Event Handler Is Not Executed

  • Event Handlers Are Not Raised

  • RadButton Not Performing Postback

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