Page not updating after ajax call - ajax

I have a custom component (that is, an xhtml file with ui:composition inside) where I have a file upload field. When a file is selected it is uploaded via AJAX like this
<uc:fileUpload
id="#{id}fileUploadComponent"
idSuffix="#{id}fileUploadSuffix"
value="#{fileUpload.docsFilePart}"
accept="#{fieldWrapper.acceptedFileTypes}"
widgetVar="#{id}documentUploadWidget"
nullAllowed="#{!((fieldDef.mandatory and
fieldWrapper.getCurrentFileCount() lt 1) and isSaving)}"
maxSize="#{customField.maxFileSize}" >
<f:ajax listener="#{fileUpload.uploadNewFile(fieldWrapper)}" render="#{localId}fileUploadMain messages"/>
</uc:fileUpload>
Below this upload there's a <div> with the same id as specified in the render attribute of the ajax call, where links for downloading the files are shown. What happens is weird - after a file is selected, it is uploaded, the <div> is updated correctly with a link to the newly uploaded file. However when I click "Cancel" or "Save" on the page, their according actions are called, a correct response is returned to the browser (with status 200) but the browser seems to ignore it - the page is not visually updated or anything...
The custom component is quite big piece of code with not-so-easy-to-rewrite logic so replacing it at this point will be... hard...
One thing to not might be that uploading the file happens in a separate controller, while the main page controller is another one. This is because the separate controller is supposed to handle uploads from the custom component.
I can't really understand what exactly happens, even less why, and I'll appreciate any ideas!
For what it's worth, I am using Mojarra on Wildfly 11 (the one provided by the AS)

As it turns out, the reason is that file uploading via JSF AJAX causes the creation of an iframe called "JSFFrameId" and that frame being set as the target of the nesting form. After the AJAX request completes the target is not removed/cleared thus causing responses to go into that iframe and breaking the view.
At this point I am not sure what causes this, but a workaround for me is to have onevent in the <f:ajax> definition, that clears the form target, like this:
<f:ajax
listener="#{fileUpload.uploadNewFile(fieldWrapper)}"
onevent="function(e){if (e.status == 'complete') { $(e.source).parents('form').attr('target','');}"
render="#{localId}fileUploadMain messages">
I will check what other states may need handling but basically this solves the problem. It may be useful if someone shares their suspicions on what may have caused JSF to leave behind this iframe and not reset the target of the form.

Related

Wicket replacing panel with ajax fails with MarkupNotFoundException

the page markup has
<div wicket:id="stepPanel" />
tag in it and when the page is first loaded it works great that is
add(new MyFirstPanel("stepPanel"));
works fine. But then when I trigger an Ajax event and request redrawing
addOrReplace(new MySecondPanel("stepPanel"));
target.add(MyPage.this);
i get the following error
Last cause: Failed to find markup file associated. MyFirstPanel: [MyFirstPanel [Component id = stepPanel]]
please note that it tries to find the wrong markup (should look for markup for MySecondPanel) and it fails regardless it succedded to do so before!
I instantiate panels using reflection, but could it be a problem here? No exceptions thrown.
Anwser:
Actually it was something else - I have noticed that one of my AjaxSubmitLinks had reference to a form that was no longer placed in a markup... so whatever you do just remember not to leave that reference.
You are adding MyPage after replacing the Panel causing MyPage to re-render.
There is a good example on how to replace panels here.
Yes you can call panels via reflection. I don't clearly know what you are trying to do with event here but if you want you can attach your panel with AjaxSelfUpdatingTimerBehavior and define the duration which will update this component in the given time period.
Hope its useful.

Can I delay loading of some controls on an xPage to after page loaded

is it possible to delay loading of some controls on an xpage?
This is the problem: let's say you have a control that does a fultextsearch and displays the result in a repeat control. this ft search might take a long time and will hold the webpage loading in a waiting state until the search result is ready.
I want my page to load most of the data initally, and some "time consuming" controls should be loaded in to the page as a sperate request after the inital load.
this way the user will immediatly see the webpage, but some of the data on the page will load a little bit later without holding the webpage in a waiting state from the server.
possible?
The downside to using rendered is that all the value bindings will still evaluate, even if the corresponding markup isn't sent to the page. So the trick here is making sure the components don't even exist until you want them to.
Every component has a getChildren() method. This returns a mutable List of components, which has a add() method. This allows you to add components to the page on the fly, either while the page is loading, or later during an event. For the purposes of what you're trying to do, you would want to defer adding the "expensive" components until a subsequent event.
Create an event handler attached directly to the view root (), give it a unique ID (e.g. "loadExpensiveComponentsEvent", set its refresh mode to partial, set a refresh ID to whatever div or panel will contain the search results, and set its event name to an arbitrary event (e.g. "loadExpensiveComponents"). This prevents your event from being triggered by actual user behavior. Set the event's code to SSJS that will inject your components.
Then add a script block () to trigger the event after the page has loaded:
XSP.addOnLoad(function(){
XSP.firePartial(null, "#{id:loadExpensiveComponentsEvent}");
});
Your page will load without the search result components. Once the page has fully loaded, it will trigger the component injection event automatically.
For guidance on how to code the injection event, open the Java file that has been generated from your existing page to see what components need to be injected and what to set their values to.
You can pack them into a panel and set their rendered status to rendered=#{viewScope.pageFullyLoaded}. Then in the onLoad event have a XSP. partialRefresh request where you set viewScope.pageFullyLoaded=true
A little ugly but doable. Now you can wrap that code into your own custom control, so you could have a "lazyGrid", "lazyPanel" etc.
Not sure why I did not think of this before. the dynamic content control in extlib actually solves this problem. the dcc can be triggered onClientLoad both using javascript and ssjs afer the page has loaded.
one problem I am facing now is that I am already using the dcc on my site so I need to put another dcc within my dcc. and this seem to be a bit buggy. I have reported it to the extlib team on openNTF.

AJAX and iFrame: Calling AJAX from inside the iFrame to Update an Outside DIV

I have a page where a user can upload a file along with some other input. Because I wanted this to be AJAX-like, I resorted to using an iFrame to accomplish this.
After the file is uploaded and an iFrame is loaded with a response page, I need to update a DIV outside of the iFrame with an AJAX call. The reason for separate updates, is that the result of the outside DIV depends on the input that the user provided with the file input.
Can this be done? Am I approaching this the wrong way?
Thank you!
UPD: Can the returned client code from within the iFrame "see" elements outside that iFrame?
Write your code in the onload event of the page loaded into the iframe. Then top will give you the top frame or parent will give you the parent frame.
Yes , it can be done. But you can do away with,the need for an AJAX-call , to update the outside the div.
Have your, servlet(assuming you are using JSP/servlets) that accepts the mutlipart request(the servlet that accepts the upload), return the intended response (to be shown on the refreshed iFrame), and ALONG WITH IT, the necessary information from the file input. This way you have all the necessary details on the client, in one response. A simple javascript function can achieve , updating the outer div with the information from the file input.

Detect when AJAX changes HTML in a DIV in WebBrowser

After I load a page through a WebBrowser, and I click a link that fires an AJAX script, I need to detect when the AJAX java script finishes loading HTML changes into a div. Since no DocumentCompleted event is fired when the AJAX script is run, I don't know when it finish running. Is there a way I can attach an event to be raised after I know 100% that the javascript finished changing the div?
The project is in C#.
Thanks
I did something similar recently (using jQuery):
$('#mydiv').change(function(){
// do stuff
}
);
Granted, I also use jQuery to set the HTML of that div. I suppose one non-jQuery approach for you could be to set HTML through your own function, which in turn can fire an onchange event.
#New in town: From my experience that is not correct. I use this on multiple DIVs that never get focus in the first place, and it works well and consistently. The normal behavior is as you describe, and normally only applies to the INPUT and SELECT elements, but this is not the case with jQuery.
There is no event. You must patch the JavaScript callback that the browser runs when the reply for the AJAX request comes in. This will contains code like "div.innerHTML = ...". Just put your code below that.

onLoad or similar for Ajax?

Good day,
I was wondering if there is a way to make Ajax move on to the next code segment only when all the elements included in the server-side code page are fully loaded. When the retrieved data is text-only there’s no problem, but sometimes there are photos included.
This is part of the code I have been using:
xajx.onreadystatechange = function(){
if(xajx.readyState==4){
document.all.div1.innerHTML = xajx.responseText;
document.all.div1.style.display = “”;
}
}
The thing is that when the response is retrieved (readyState set to 4) and div1 is displayed, the Photo has not been completely loaded yet, so actually the user can see the process of the picture slowly appearing, as he would in any other “normal” case. What I want to do is making div1 available for display only once all the components are fully loaded while meanwhile the system does its stuff in the background. Before Ajax I used hidden iframes like everybody, so I could enclose an onload event handler within the iframe tag (or in an external script), so div1 would appear only after the iframe has fully loaded, photos included.
Any idea?
You can use the 'onload' event on images themselves. You'll need to work out how to attach that event when you are downloading the code dynamically as in your case.

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