Prevent Flicker from Ajax CollapsiblePanelExtender on Postback
Let’s see how to fix the flickering of the CollapsiblePanelExtender when collapsed is set to true (Collapsed="true")
Here is my CollapsiblePanelExtender
<cc1:CollapsiblePanelExtender ID="CollapsePanel1" runat="server" SuppressPostBack="true" CollapseControlID="btnCancel" Collapsed="true" CollapsedText="Show Time" ExpandControlID="imgPostQuestion" ExpandedText="Hide Time" TargetControlID="panelPost"> cc1:CollapsiblePanelExtender>
Your TargetPanel is here
<asp:Panel ID="panelPost" runat="server" CssClass="cpBody">
<div>
//Ur collapsible Content
div>
asp:Panel>
And now we are preventing the flickering by the CSS style and the style is as follows.
.cpBody
{
height:0px;
overflow: hidden;
}
There we found the solution for the flickering..