I have asked this same basic question before several times without a response, but let me try one more time, breaking it down as simple as possible.
I have a strongly-typed view with a hidden field on it.
When the view renders server-side, I am setting the value of the hidden field to a property of the model.
When the view renders client-side, I want to get the value of the hidden field (that was set during the server-side render) and display it in a java script alert box.
This should be a simple thing to do and yet I am unable to make it work. I have set a break-point in the view and I can see that the hidden field is being set to the correct value. But the javascript will not display that value.
The page/view being rendering has been gone to before. At the time I want to display this alert, I am going back to that page and now I want to see the alert.
It is as if the page is being cached, so instead of using the new value for the hidden field it is using the old value (from the first time the page was visited). If the DOM is being cached, how I can prevent that so that each time I visit the page I get the updated values of the page and not the cached ones? What am I doing wrong??
#<input type="hidden" id="hdnShowMsg" value="#Model.ShowMsg" />
<script>
alert($('#hdnShowMsg').val());
</script>
Your script may be firing before your document is fully rendered. Use the jQuery document ready function.
http://api.jquery.com/ready/
<script>
$(function() {
alert($('#hdnShowMsg').val());
});
</script>
Also note that document ready is not supported within a jQuery Mobile document and you may run into problems depending on what part of the DOM you are trying to manipulate.
Use $(document).bind("pageinit", function() {}) instead.
http://jquerymobile.com/demos/1.2.1/docs/api/events.html
Related
I am having trouble with only firefox. My page shows a tree structure that is loaded via ajax as the user clicks on the nodes they want to expand. The problem I'm having with firefox, and only firefox, is that it will expand the nodes on the first page load. But after that firefox caches it weird and the node header, not children, of the ajax request gets carried over to the new page. This is an issue because the node's header that is carried over contains information that determines if the node has retrieved it's children.
<div class="node topbar"
<input type="hidden" id="foo" name="hasretrievedchildren" value="1"/>
...
</div>
It should be as it is on the first page load.
<div class="node topbar"
<input type="hidden" id="foo" name="hasretrievedchildren" value="0"/>
...
</div>
My Javascript checks for a nonzero value on that input to do the AJAX call.
Is this a bfcache issue?
I'm lead to believe it's not because I added
window.onunload = function();
to the js file and in a script tag and neither fixed it which this article
https://developer.mozilla.org/en-US/docs/Using_Firefox_1.5_caching
says should invalidate the bfcache.
I'm using asp.net MVC 4 and I tried using the MVCdonutcaching to set this page and partial views to not cache. But that didn't work either.
Maybe it's the bfcache, maybe it's not.
I had to face the same problem some time ago. The browser caches were causing some strange behaviour on our forms, and it was affecting the expected results of the page.
Someway to solve itSomething you can do in order to make the program load always the correct value (assuming you are loading it from ) is to initialize the value through your Javascript.
If you use JQuery, you should use:
<script type="text/javascript">
$(document).ready(){
//Assign your items values here
}
<script>
You can also use the onload handler in JS.
Hope this helps.
I was able to solve the problem. Firefox caches all form data even hidden inputs. Since I was using a hidden field to store the flag that enabled the AJAX request it would reload the form data with the flag set. I moved it to a custom attribute and it works exactly as it should.
Select boxes converted to Select2, do not automatically integrate with unobtrusive validation mechanism in ASP.NET MVC framework.
For example, on a form which contains a regular select box (marked as required in model definition), submitting the form while no options have been selected in the select box, will cause the border and background of the select box to take a reddish color, and by using #Html.ValidationMessageFor, error messages, if any, can be displayed beside the box. However if the select box is converted to a Select2 component, then none of the mentioned features work any more. Even the validation error message will not show up.
It seems that the reason for even the validation error message not showing, is because Select2 changes the display CSS property of the original select box to none (display:none), and I guess the unobtrusive validation script does not bother generating error messages for invisible fields.
Any ideas / solutions?
This issue isn't really specific to Select2, but rather to the jQuery unobtrusive validator.
You can turn on validation for hidden fields as highlighted in this answer.
$.validator.setDefaults({
ignore: ''
});
As the comments noted, it didn't work inside an anonymous callback function within $(document).ready(). I had to put it at the top level.
I've run into similar issues with the select2 plugin. I don't know exactly which features you're using specifically, but in my experience, when you set an element as a select2 in the document.ready event, the plugin will change some of the element's attributes on the fly (inspect one of the elements after your page has finished loading - oftentimes you'll see the id and class properties are different than what you're seeing when you view source).
It's difficult to offer more without actually seeing the code, but here's a few ideas to get you started:
First off, obviously make sure you have the a link to your select2.css stylesheet in the header.
Then, since you're talking about form submissions, I'd recommend you examine whether or not you're getting a full postback or submitting via AJAX (if you're using jQueryMobile, you're using AJAX unless you override it in the jquerymobile.js file or set a data-ajax="false" in your form attributes). You can just look at the value returned by Request.IsAjaxRequest() for this. Obviously if you're submitting via ajax, you won't hit the document.ready event and the select2 won't initialize properly and you'd need to figure out a way around that. Try refreshing the page after the submit and see if it renders the select2 component.
Then I'd suggest examining the elements and see if they're not behaving like you'd expect because you're actually trying to work with classes that the plugin has reassigned at runtime. You can either just adjust your logic, or you can dig into the select2 code itself and change the behavior - it's actually fairly well-documented what the code is doing, and if you hop on the Google group for select2, Igor is usually pretty quick to follow up with questions.
like this
$('select').on('select2:select', function (evt){
$(this).blur();
});
$('body').on('change', 'select.m-select2', function () {
$(this).blur();
})
I have a complex ICEFaces XHTML page that renders certain components conditionally, based on flags set as the user enters data on the page. What I'd like to do is direct focus to a certain field as soon as it appears, which may not be during the initial render of the page.
The ICEFaces documentation suggests that I can do this using the focus attribute of the outputBody component. Specifically:
If you setting the initial focus, the focused component must be rendered on first render call, if not then set the focus attribute only when the component gets rendered.
This seems to suggest that I can manipulate the value of the focus attribute at the time that my conditional component gets rendered. However, I don't see any attributes of the inputText component that allow me to change a value at the time the component is rendered.
Am I misreading the documentation? When and where can I alter the value of the focus attribute of outputBody so that my conditionally-rendered field gets the input focus when it appears? Or am I using the wrong tool to solve this problem?
Maybe you can use this
JavascriptContext.applicationFocus(FacesContext.getCurrentInstance(), "form:fieldM");
You can use some Javascript to set focus on an element.
Here's the Java snippet required to do this:
JavascriptContext.addJavascriptCall(FacesContext.getCurrentInstance(),
"document.getElementById('myForm:myTxtBox').focus();");
myTxtBox is the ID of your form element, and myForm is the ID of your form.
You can use this wherever you are changing certain variables' values to render/hide fields.
Due to the fact that I'm using both Seam and ICEFaces, I was not able to invoke Javascript reliably from my server-side Java code. I was, however, able to add the necessary Javascript in-line in my XHTML, within the ui:component that was being conditionally rendered, close to the input field I needed the focus to go to. The relevant section of my XHTML looks like this:
<ice:panelGroup id="textPanelInput" >
<ice:form id="textInputForm" partialSubmit="true" style="vertical-align:middle;">
<ice:inputText id="textInput" valueChangeListener="#{appField.valueChangeListener}"
size="#{appField.fieldDefLengthAsInt}"
value="#{appField.value}"
styleClass="fieldStyle" rendered="#{appField!=null}"
>
</ice:inputText>
<ice:message id="jo" for="textInput" />
</ice:form>
</ice:panelGroup>
<script type="text/javascript">document.getElementById('panelsFields:0:textInputForm:textInput').focus();</script>
The Javascript line at the bottom is the line I added to solve my problem. All of the code above is in a ui:component block that may or may not be rendered, based on other conditions. When this ui:component block is rendered, my Javascript goes with it, and sets the input focus to my desired input field.
ICEfaces supports javascript api which has setting focus function. Thus you may use it like in the next excerpt:
<script type="text/javascript">
jQuery(document).ready(function () {
ice.applyFocus(elementId);
});
</script>
elementId is jsf component clientId.
ICEFaces javascript Api
I have a "change password" page that needs to hash any passwords entered on the page via Javascript before sending. To complicate it, the page is loaded via a jQuery load() call, and is submitted by a jQuery.Form ajaxForm() call. Had everything working in MVC2, but MVC3 is giving me trouble.
That is, I have a page with a "Change Password" link that when clicked, loads the change password page into a jQuery modal popup, then the form on the change password page get's submitted via the jQuery.Form library (Essentially just wraps a $.ajax call), and returns it's result into the modal same modal popup.
Essentially, I have a model with two properties, OldPassword and NewPassword. I have two hidden fields generated by by view for these. They hold the hashed value of two other fields, PrehashOldPassword and PrehashNewPassword, and get updated via keyup events (I know, this means it does a whole SHA256 hash on every keyup... inefficient, but got the job doen for testing). The key here is that the regex validation and required field validation needs to be executed on these Prehash fields, which exist on the client side only (As obviously I don't want to transmit these fields to the server in any way).
So I manually create these two and add on the data-val-* attributes to the elements, i.e. they are NOT generated by the MVC helpers, etc. I am guessing that this is where I'm missing something. When the form submits with all fields empty, all of the errors popup that should, but the form goes right ahead and submits anyway.
==
So the things I've tried:
Yes, the unobtrusive library parse() method already get's called to parse the AJAX loaded form contents, and it appears to get all of the data validation stuff correctly, since I see the errors show up as fields blur(), and when I hit submit (before the ajax request completes and replaces the content of the popup).
Possible note: this call to the unobtrusive library's parse method happens AFTER the AJAX successfully loads the change password page into the popup... the AJAX form submit binding is put on document.ready of the loaded content, ergo, the AJAX form submission binding MAY be binding prior to, and thus firing before, the validation calls that the parse method may bind to the submit event...
However, (1) I am doing this same sort of thing in other places without issue, the ONLY DIFFERENCE being that I am manually putting these data-val-* attributes on elements I am creating manually! And (2), if I cause some kind of error on the OldPassword or NewPassword fields, i.e. a required field validation error by not loading a value into them, they display their error, and successfully STOP the form from submitting through the jQuery.Form method.
So I think something has to be wrong here:
<input id="PrehashNewPassword" type="password" name="PrehashNewPassword" data-val-required="The password field is required." data-val-regex-pattern="<%= RegexHelper.PasswordRegularExpression %>" data-val-regex="<%= RegexHelper.PasswordRegularExpressionError %>" data-val="true" />
I know that jquery.validate is getting the rules right, since I DO see the errors. It's just not stopping the form from submitting when their is an error in these manually generated elements, unless I do something like this, and add a pre-submit callback on the form's AJAX submission:
$("#ChangePasswordForm").ajaxForm({
beforeSubmit: function () { if (!$('#ChangePasswordForm').valid()) { return false; } },
target: '#overlay'
});
While this works, it is kind of ugly and I believe it causes the validation to be called twice... Not a huge deal, but less than ideal. So is there some other call that I need to make in the unobtrusive library to bind these?
Not sure if you found the problem, but you may try to
return false
in there if the form is not valid...
.
.
.
if (!$('form').valid()) {
return false;
}
// JSON POST...
.
.
.
If that doesn't work, then you could try to use:
$.validator.unobtrusive.parse($("#dynamicData"));
after dynamically adding your custom inputs. "dynamicData" is the ID of an element wrapped around the form
above found from here: http://weblogs.asp.net/imranbaloch/archive/2011/03/05/unobtrusive-client-side-validation-with-dynamic-contents-in-asp-net-mvc.aspx
Out of interest, what happens if you just get the form to validate?
<script type="text/javascript">
$("form").submit(function (evt) {
// validate here should trigger invalid fields
$('form').valid();
// JSON POST...
// stop form submitting
evt.preventDefault();
});
</script>
I've got a model that does some validation checking and adds the errors to ModelState:
ViewData.ModelState.AddModelError("mycontrol", "message")
They display fine on the view side, but is there a way to set the focus to the control that corresponds to the validation message? Right now, the page refreshes and stays at the top of the page, so if the error is towards the end of the page, it's not obvious to the user what happened.
Note: Another solution would be for ValidationSummary to show the list of errors at the top of the page, but I've never been able to get it to display anything. All my errors are displayed via ValidationMessage.
Edit: I found my problem with ValidationSummary. The markup I had was:
<% Html.ValidationSummary()%>
which should have been:
<%=Html.ValidationSummary()%>
I'd still like to know how to snap to the field with the error however.
Some jquery goodness to scroll to the first input with an error. The tricky bit is that you have to get the underlying DOM element BEFORE you invoke focus() as the focus() method on a jQuery object fires the focus event instead of giving focus to the element.
<script type='text/javascript'>
$(document).ready( function()
{
var input = $('.input-validation-error:first');
if(input)
{
input.focus();
}
});
</script>
You could use JavaScript to find the input elements on the page that have the MVC validation HTML class (input-validation-error) added, and move the carat to the first one. That /should/ move the screen to that element although I haven't tested it.
A JS library such as jQuery will make this straightforward to do.