Patch that changes the UpdateElements so that any JavaScript calls being coalesced will be added to previous javascript calls instead of replacing. Created against 1.8.2 open source code.

If JavaScript calls are accumulated rather than coalesced, a slow client will be required to play back a sequence of all intermediate states of the application rather than being able to catch up to the current state. In extreme cases, the client may not be able to play back the events at the same frequency delivered by the server and may never catch up.

We would like to discuss the application features in more detail to understand the role of this patch better.

I'm happy to provide more details. Would you like them included as part of this Issue, or through another mechanism?

Please provide some examples here in preparation for a meeting.

We may need to provide both "coalescing" and "concatenating" JavaScript call regions: the examples will help to clarify this.

To properly solve the issue code concatenation we would need to introduce another command type (EvalCode?) that will have its own coalescing rules relative to the itself and the other types of commands that can be sent to the browser.

For this particular problem, our ICEfaces application receives asynchronous events from our Server component. The first event instructs the client to assign focus to a specific field (which we implement using the requestFocus() method). The second event returns data that was evaluated asynchronously (we update our model with the value). In both cases, Server Push is used to send the updates to the browser.

What we were finding when the issue was raised was that the javascript created that assigned focus was lost by the subsequent UpdateElements (which contained Javascript used for manageing modal dialogs and autocomplete components). It seems to be an intermittent problem, but we thought this was more due to inconsistent time spent in the server triggering these events into the client. I've tried to return some relevant data without our patch in ICEfaces, but due to the difficulty in recreating the error, I am having trouble supplying something to look at.

Whenever we get any updates sent to the browser, we're seeing Javascript for modal dialogs and autocomplete components. I think this is part of the issue, in that both async events trigger updates that contain javascript calls. In the case where the icefaces app receives the Focus async event first, it has the Focus javascript in the UpdateElements. Then, when the Async Deriv event is received, it has Javascript for modal dialogs and autocomplete components. Commands like

new Ice.Autocompleter('mainForm:field_LayFact2024_08082003_090159-Contact-Type','mainForm:field_LayFact2024_08082003_090159-Contact-Type_div',

,'iceSelInpTxtRow mandatoryFieldRow','iceSelInpTxtSelRow mandatoryFieldSelRow');

When these two commands are coalesced, the original Javascript is lost and focus is never assigned to the desired field in the browser.

However, looking at this again more closely, I'm not really happy with the patch either. We're getting a lot of duplicated calls in the javascript, in regards to the modal and autocomplete calls (one per coalesced command). I've been having a bit of a play, and find this to be a better fit for our app. I've tried to make a patch file that compares the new UpdateElements.java field with the original, unpatched file. Hopefully, it can be applied. It's adding a new private method that attempts to coalesce the Javascript commands (split by semi colons), instead of a blanket replacement. This is working nicely for us locally, as we're preverving all of the javascript events while not duplicating javascript commands that existed in the previous UpdateElements object.

I hope this is enough to go on.

Version 2 of what we've done locally

The root cause in this case appears to be extra JavaScript being generated by modal popups and autocomplete. Assigning to Ken to consider these component bug fixes for P02.

Changed popup panel component and renderer to send the JS code controlling the popup in the client only when the visibility is changed. This way the code sent for hiding the popup is send only once after the popup was made invisible, any other actions that won't change the visibility will not trigger JS updates for the popup.

Changed Auocomplete renderer so that the JS initalization code is sent only on page load or component markup update. The code is rendered in a <script> element along with the rest of the markup instead of using JavascriptContext API.

Tweaked the PanelPopup visibleBefore change to use state saving, so it would pass our SerializedViewTest automated test.

icefaces trunk
Subversion 23111

icefaces2 trunk
Subversion 23112

It seems this change to panelPopup is causing a new regression failure with the none-functioning of the panelPopup autoCentre and autoPosition attributes:

New failure: ICE-2368 all browsers (the position panel and autocenter popup Panels are not working)
This problem is reproducible on component-showcase too

Changed renderer to output JS code in the markup so that a DOM diff is triggered when popup coordinates changed.

ICE-2368 test case is changing the visibility and rendering state simultaneously which confuses the logic used for track the changes in visibility state. To fix any future interference between render and visibility state processDecodes method is used for saving visibility state because the method is always called, not only when the component is rendered.

BTW
Last behavior of popup panel from Icefaces revision 23102 was unstable. Component showcase draggable panel not always is visible on button enabling. Just try to switch few times between modal and draggable.

BTW2
We still use Icefaces from revision 20815(2010.03.01). Similar problem with addJavascriptCall we resolved with much simplier patch. In PanelPopupRenderer at the end of method encodeBegin instead call

JavascriptContext.addJavascriptCall(facesContext, "Ice.iFrameFix.start('" + clientId + "','" +
CoreUtils.resolveResourceURL(facesContext, "/xmlhttp/blank") + "');");

we use only
if ( (modal == null || !modal.booleanValue() ) )

Krashan, we are unable to reproduce any issues with draggable not always working. Please ensure your browser cache has been cleared and that you have the latest JS, etc.

The popup panel is not working correctly on icefaces2/trunk compat component showcase as of svn rev# 23167.

• Modal popup is not modal.
• Draggable popup is not draggable.
• Autocentre popup does not autocentre.

Note that icefaces/trunk popup is working correctly.

Changed PanelPopupRenderer in icefaces2.0/compat to render the JS code as unescaped text. This way browsers interpret the code correctly when updating the elements that include scripts.

Hi. I've applied 1.8.2 EE Patch 2 to our application, and I get the original error again: attempts to assign focus to a field using Server Push sporadically fail. When I reapply the changes to UpdateCommand as provided in the Patch, the behaviour works consistently (the focus is assigned to the correct field). It still appears that if commands are coalesced, earlier javascript commands are lost if the new command being coalesced contains its own Javascript value.

I have not tested this with 2.0.

I'll have a look.