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Showing and Positioning

By default, windows are not visible on the page, and appear centered on the screen. You can change this behavior with no code at all by setting a few properties:

  • Set the VisibleOnPageLoad property to True to make the window visible when the page loads. You can set this property on an individual RadWindow object if you want only one window visible, or in the RadWindowManager if you want all your windows to be visible when the page loads.

  • Use the Top and Left properties to specify the position of the window relative to the HTML page. Top and Left give the offset, in pixels, of the top left corner of the window. If you set the OffsetElementId property to the ID of an HTML element, the window offset is relative to that control rather than to the top left corner of the web page. By using OffsetElementId, you can control the position of the window relative to the rest of the page element flow, independently of the screen-size and automatically adjusting to the changes in the page layout.

  • Use the OpenerElementId property to specify the ID of an HTML element that, when clicked, automatically opens the window. OpenerElementId lets you open the window in response to client input without writing any JavaScript.

The OpenerElementId and OffsetElementId properties are of type string, and expect the client-side ID of an HTML element. If you want to specify an ASP.NET control such as Label, Link, or Button, use its ClientID property. This can be done by setting the properties in codebehind as shown below.

<asp:Button ID="ServerButton" runat="server" Text="Open RadWindow from a Server Button" />
<br />
<input type="button" id="HtmlButton" value="Open RadWindow from HTML Button" />
<telerik:RadWindow RenderMode="Lightweight" ID="RadWindow1" OffsetElementID="HtmlButton" OpenerElementID="HtmlButton"
    NavigateUrl="" runat="server">
<telerik:RadWindow RenderMode="Lightweight" ID="RadWindow2" NavigateUrl=""
protected void Page_Load(object sender, EventArgs e)
    RadWindow2.OpenerElementID = ServerButton.ClientID;
    RadWindow2.OffsetElementID = ServerButton.ClientID;
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    RadWindow2.OpenerElementID = ServerButton.ClientID
    RadWindow2.OffsetElementID = ServerButton.ClientID
End Sub

See Also

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