Chapter10: Placing Ajax controls

liveToLearn · June 20th, 2012, 02:33 PM

Hi,

This post is regarding a page flicker issue. I have a master page that link to multiple aspx pages, the master page includes one contact form and a menu bar. However, the flicker issue is not happening at all with the form. In this case, it is happening whenever I click on any menu item that links me to an aspx page (this only happens with IE9). To solve this issue, I thought maybe I should apply the concepts I learned in chapter 10 about the AJAX controls (Update Panel and Script Manager). So, I wrapped the menu list with an update panel and before it, I added a Script Manager control. Now I get the following error: "Control 'ScriptManager1' of type 'ScriptManager' must be placed inside a form tag with runat=server. " Now, there is only one form allowed in the the master page, so how to overcome this flicker issue?

Thank you.

Imar · June 21st, 2012, 01:58 AM

Hi there,

By design, this is not going to work. The UpdatePanel avoids page flicker on postbacks. That is, when a page posts back to itself. This work because it only replaces the piece if HTML that has changed by the postback (the contents of the UpdatePanel's ContentTemplate).

When you request a new page you don't post back, but issue a GET request on a new ASPX page. The UpdatePanel has no way of dealing with this and as such you always get "page flicker". You can overcome this in IE by using some meta tags as explained here: http://imar.spaanjaars.com/314/smoot...ge-transitions Note, this only works in IE. Note 2: not sure if this still works in recent versions of IE; haven't used it in a while.

Finally, you can add the ScriptManager to the MasterPage as the first control in the form. This way, it's available to all pages. This does not solve the page flicker issue; I just mention it here for other cases where you need a ScriptManager control.

Cheers,

Imar

liveToLearn · June 21st, 2012, 08:00 PM

Hi Imar,

Thank you so much for your very helpful replies!