Have a AJAX UpdatePanel in a MasterPage file:
<asp:UpdatePanel ID="upnlTimer" runat="server" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="tmrCountdown" EventName="Tick" />
</Triggers>
<ContentTemplate>
<asp:Timer ID="tmrCountdown" Enabled="false" runat="server" Interval="1000" />
<asp:Label ID="lblTimer" runat="server" Text="TEXT"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
When i goto debug everything works well, dont get the postback flash as the timer counts down.
But when the user makes a selection from a RadioButtonList, of course the SelectedIndexChange events fires off and the PostBack goes off as expected.
One problem i am having though is that the UpdatePanel with the Timer/Label is freezing, albeit fractions of a second, but over time it can increase the time-alloted for the test by up to a full minute (60 secs) pending on the number of questions being asked.
Question:
Is there a way to isolate the PostBack away from the Timer UpdatePanel from the Question List? Placed an UpdatePanel on the Content Page
Would it be better to place the ContentPlaceHolder, in MasterPage, within a UpdatePanel so that its postbacks are isolated from the Timer UpdatePanel?
If i isolate the CPH, as #2, I can still access the MasterPage file name as i am right now CType(me.Master, Main).Event?
Having a problem with the Content Page UpdatePanel, either conflicting or stopping, the MasterPage Timer UpdatePanel. How would i go about fixing this problem?
I think you are experiencing the annoying timeout of UpdatePanel.
I suggest you try to improve any code in the SelectedIndexChanged of your Radiobutton or try another approach without UpdatePanel.
Related
I have an ASP.NET Repeater Control inside an UpdatePanel. I need to update another control when clicking in an ImageButton (inside of the Repeater template). The thing is that I can't get that to trigger.
The panel upPanelRotator is refreshed... which I don't want...I just want to call back to server to update another panel - which I'll control from the server.
Any ideas?
<asp:UpdatePanel ID="upPanelRotator" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Repeater ID="rptRotator" runat="server" OnItemCommand="rptRotator_ItemCommand">
<ItemTemplate>
<asp:ImageButton ID='imgBtn' runat="server" />
</asp:Repeater>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="imgBtn" EventName="ItemCommand" />
</Triggers>
</asp:UpdatePanel>
You should be able to add an async postback trigger to the updatepanel you want to update. Set the control id of the repeater and the "ItemCommand" event as the event name... like this:
<asp:UpdatePanel ID="updatePanel2" runat="server" ChildrenAsTriggers="false" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="repeaterId" EventName="ItemCommand" />
</Triggers>
<ContentTemplate>
...
If PanelA has the trigger button, and you want to update PanelB, you would need to have the async postback trigger on the UpdatePanel surrounding PanelB. The problem is, you need to give the actual ID's of the buttons, which specifying imgButton like you have above won't work (because there could be many in the repeater, and async trigger requires one reference that it won't be able to find). To make this very simpe, wrap everything in the UpdatePanel, and that will make your life easier. Otherwise, you have to add the async postback triggers from code I believe.
I have right now similar situation, and I have do this so that I wrap control inside Repeater in another UpdatePanel, and I set AutoPostBack="true" of that control, and register
< asp:AsyncPostBackTrigger ControlID="imgBtn" EventName="Click"/ >
my only consideration on this is how will a such number of UpdatePanels reflect upon performance. I have small project with few DB entry's but for larger amounts of Data, I would test performance before and after such intervention.
I have a C# .net 4.0 website project with a fairly complicated filtered search page on it. There are multiple UpdatePanels that are added within a Repeater. When one UpdatePanel does a postback - all the other UpdatePanels also postback at the same time.
This becomes a problem because there can be lots and lots of UpdatePanels dependent on the number of items the user chooses to view. I know UpdatePanels are not ideal - I didn't write this but have to try and fix it quickly!
There is LandingPage that holds an UpdatePanel with a Repeater control inside. Within the repeater is a user control called Article. The Article control contains some HTML and a second user control called Save. The Save control has an UpdatePanel too.
The problem I have is that only the first btnSave event gets raised. So if I click "btnSave" it works but all subsequent button click events do not fire.
I have also noticed that ALL instances of the UpdatePanel in the Save control postback at the same time - is this normal?
So a simplified view of the page is like so:
LandingPage.aspx
<asp:UpdatePanel ID="pnl" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<asp:Repeater ID="resultsRep" runat="server">
<ItemTemplate>
<uc:Article id="Article1" runat="server" />
</ItemTemplate>
</asp:Repeater>
<asp:Button id="btnLoadMore" runat="server" Text="Load More" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnLoadMore" EventName="Click" />
</Triggers>
<asp:UpdatePanel>
Custom User Control "Article"
<asp:PlaceHolder ID="ArticlePanel" runat="server">
<!-- Assorted HTML stuff here -->
<uc:Save id="Save1" runat="server" />
</asp:PlaceHolder>
Custom User Control "Save"
<asp:UpdatePanel ID="ctl" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="True">
<ContentTemplate>
<asp:LinkButton ID="btnSave" runat="server" OnClick="btnSave_Click" CausesValidation="False" Text="Save" />
</ContentTemplate>
</asp:UpdatePanel>
Thanks in advance as always.
EDIT
After further investigation, using Firebug console I found that the subsequent postbacks don't occur because the following error is thrown:
505|error|500|Invalid postback or callback argument.
Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%# Page EnableEventValidation="true" %> in a page.
For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them.
If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.|
So it seems somehow I am posting back something dodgy?
The problem was down to the use of nested UpdatePanels. I don't know where the error itself actually comes from but after trial and error I figured out that the parent UpdatePanel wasn't configured properly.
The parent UpdatePanel should have been like so :
<asp:UpdatePanel ID="pnl" runat="server" UpdateMode="Always" ChildrenAsTriggers="true">
The difference being UpdateMode="Always" and ChildrenAsTriggers="true". The UpdateMode tells the parent UpdatePanel to refresh when any of the children reload. The ChildrenAsTriggers attribute allows child UpdatePanels to cause the refresh of the parent.
So now it works - mostly. I still have the issue of every single UpdatePanels posting back everytime. Its really inefficient but I can't seem to stop it.
I'm trying to speed up my Repeater so that not as much HTML has to be resent via the AJAX UpdatePanel on each call.
So here's what I have (a very much simplified version):
<asp:Repeater ID="rptContactSteps" runat="server">
<ItemTemplate>
<p>Script:<br /><%#mobjSDIT.FormatText(Eval("script"))%></p>
<p>Notes:<br /><%#mobjSDIT.FormatText(Eval("notes"))%></p>
<asp:UpdatePanel ID="upStep" runat="server" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="rptContactSteps" EventName="ItemCommand" />
</Triggers>
<ContentTemplate>
<p>Contact/Step Notes:<br /><%#mobjSDIT.FormatText(Eval("contact_step_notes"))%></p>
<asp:ImageButton ID="btnSaveAndCompleteLastStep" runat="server" ImageUrl="~/images/content/buttons/save-and-complete-button.png" CommandArgument='<%#Eval("step_contact_tie_id")%>' />
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
</asp:Repeater>
So, when I click 'btnSaveAndCompleteLastStep' I want all the UpdatePanel in 'rptContactSteps' to update. Having the UpdatePanel inside the ItemTemplate should help prevent having to re-load the html/text that populates the Eval("script") & Eval("notes"), since the value of these variables could be very large and over a 3G connection this could be very costly (in time & money).
I though by adding the async trigger it'd work as I have used this type of trigger before, but not when inside the Repeater. Currently the UpdatePanels aren't getting updated at all, except from the one from which the button was pressed.
Any ideas anyone?
They aren't getting updated except by the one that is called because the update mode is set to conditional, and by default the ChildrenAsTriggers is set to true. So if you want them all to update when one of them is changed, then you will need to find each of the update panels in each of the repeater items and call .Update() on the update panel, or you can change the update mode to "Always", or just wrap your repeater in an update panel instead of wrapping just the items.
Does that make sense? If not I can expand.
That behavior sounds ok to me because postback from within an updatepanel will not update anything outside of it by default.
One way you can try is on your btnSaveAndCompleteLastStep click , find each updatepanel in the repeater items and call Update() on it.
I am completely stumped on this and would really appreciate any help.
I am working on a user control that is situated inside of an update panel. There is a button on the form which loads some data. This is working correctly.
There is also a drop-down box to filter the data. Changing this does initiate a post back, however nothing happens. The drop-down box goes back to it's default value the OnSelectedIndexChanged function is never called.
I've put break points in page_prerender and page_preload and both are being hit the post back is definitely occuring. Breakpoints withing the dropdownGroup_changed function are never hit.
Removing the update panel solves the problem, however it breaks the rest of the page so I can't use that for anything other than testing.
I've also verified that there is nothing in my prerender / page load that is resetting the page's state.
Here is the update panel code:
<asp:UpdatePanel ID="UpdatePanel6" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional" >
<ContentTemplate>
<ucControlName:ControlName ID="ControlName1" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Here is the drop-down in question - It is located inside of the user control
<asp:DropDownList ID="dropdownGroup" runat="server" Visible="false" AutoPostBack="true" OnSelectedIndexChanged="dropdownGroup_changed"></asp:DropDownList>
It is of course visible and databound by the point in the code where the issue is occuring
A bit more info-
added Both a hard coded dropdown (To rule out a stupid databinding issue) and a textbox to the same control. I have the same issue.
It appears that the event isn't triggering because the values are never changing as far as .net is concerned. I've checked the control during page_init and page_load - the value is always the same.
The fact that the button works but the other controls don't makes me think that there is a view state issue here somewhere but I can't quite ferret out what is causing it. Viewstate is enabled for the page and the panel- don't know if anything else could be overriding / corrupting it.
Did i mention that I hate update panels with a passion? because I hate update panels with a passion.
I suggest checking the 'Value' property for each 'ListItem' in the 'DropDownList' control. If they are all the same even if the 'Text' properties are different, then the 'OnSelectedIndexChanged' will not fire at all since ASP.NET cannot tell if anything has changed (See this related question for more info.)
This was the real cause of my problem even though I, too, had a 'UserControl' with a 'DropDownList' inside an 'UpdatePanel' and the 'AutoPostBack' was firing as expected. I thought the UpdatePanel was the culprit but it was not the case. Each of the items in my DropDownList had the same underlying value of "10" even though they had distinct 'Text' values. I changed them to each have a unique value which then allowed for the OnSelectedIndexChanged event to fire thus fixing the problem.
Two answers for the price of one:
Are you calling DataBind() in your Page_Load? If you do that on a PostBack, you will lose events. Replace the call with the following:
if (!IsPostBack) {
DataBind();
}
If your DropDownList is outside your UpdatePanel, you need to add a Trigger as follows:
<asp:UpdatePanel ID="UpdatePanel6" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional" >
<Triggers>
<asp:AsyncPostBackTrigger ControlID="dropdownGroup" EventName="SelectedIndexChanged" />
</Triggers>
<ContentTemplate>
<ucControlName:ControlName ID="ControlName1" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Have you tried UpdatePanel.Update (); after your databind.
I have a rather complex custom control - the custom control has a couple of update panels in it.
I am trying to use the control like this inside of an update panel:
<asp:UpdatePanel ID="up1" runat="server">
<ContentTemplate>
<asp:Button ID="btn1" runat="server" Text="Sample Button" /> <asp:Label ID="lblTime" runat="server"></asp:Label>
<cc1:MyCustomControl ID="MyCustomControl1" runat="server" >
</cc1:MyCustomControl>
</ContentTemplate>
</asp:UpdatePanel>
When I click the button in the update panel, it does an async post back and there is no screen "flicker" When I click a button in my custom control the page flickers and does a full post back.
Inside the custom control, there are update panels that are trying to do full postbacks (based on triggers).
How can I make the page level UpdatePanel not do a full postback no matter what is going in inside of the custom control?
Have you thought about explicitly setting an asp:AsyncPostBackTrigger with the btn1 control in the up1 UpdatePanel control.
<asp:UpdatePanel ID="up1" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btn1" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:Button ID="btn1" runat="server" Text="Sample Button" />
<asp:Label ID="lblTime" runat="server"></asp:Label>
<cc1:MyCustomControl ID="MyCustomControl1" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Edit: How you tried to explicitly call the Update method in the button's OnClick event for the Update Panel? This includes the Update panels embedded within the custom control.
Figured out the solution similar issue to this: How can I get an UpdatePanel to intercept a CompositeControl's DropDownList
Except my control causing the postback was in an updatepanel with a full postback trigger. I was able to pull that control out so it was not nested with in update panels and that resolved it.
I would first look if there is some other issue with the custom control causing the full page postback, as in any case what should be happening is that the whole update panel refreshes (still with ajax).
After that, just look at the Nesting UpdatePanel Controls section of this:
http://msdn.microsoft.com/en-us/library/bb398867.aspx#
Also make sure to have the ScriptManager control with the property EnablePartialRendering set to true.
On the UpdatePanel, set the property ChildrenAsTriggers="true". This tells the UpdatePanel to intercept all PostBack invocations that originate from inside the UpdatePanel.
You may want to also explore the UpdateMode property, which determines what kinds of events trigger an update. (By default, an UpdatePanel will refresh if any other panel on the screen gets refreshed. This threw me for awhile until I realized what was going on.)