How to use RadWindow OffsetElement with animations
How to
Use an animation when opening a RadWindow that must have a certain position according to an HTML element on the page (OffsetElement).
Description
Currently the RadWIndow's animation takes place before it is repositioned according to the Top and Left properties when an OffsetElementID is set. This means that in this scenario the animation will take place in the center of the screen and when it is finished the RadWindow will be positioned properly. This would rarely be the desired effect, yet for the time being this will not be changed internally to avoid a breaking change.
Solution
You can use the OnClientBeforeShow event to set the position of the RadWindow according to the desired element via jQuery and the RadWIndow's client-side API. Thus instead of setting the Top, Left, OffsetElementID properties you need to have them in JavaScript variables:
<telerik:RadWindow ID="RadWindow1" runat="server" OpenerElementID="Button1" Animation="Slide"
OnClientBeforeShow="windowBeforeShow">
<ContentTemplate>
sample content in the RadWindow
</ContentTemplate>
</telerik:RadWindow>
<div id="offsetDiv" style="position: absolute; top: 50px; left: 50px; width: 100px; height: 100px;
border: 1px solid red;">
</div>
<asp:Button ID="Button1" runat="server" Text="Open the RadWindow" UseSubmitBehavior="false"
OnClientClick="return false;" />
function windowBeforeShow(oWnd, args) {
var offsetEl = $telerik.$("#offsetDiv"); //position the window according to the div with ID myDiv
//var offsetEl = $telerik.$("#" + oWnd.get_openerElementID()); //position the window according to the OpenerElement
var coords = offsetEl.offset();
var topOffset = 120; //this is the vertical offset
var leftOffset = 120; //this is the horizontal offset
oWnd.moveTo(coords.left + leftOffset, coords.top + topOffset);
}