I'm a bit confused and sorry if this question is repeated elsewhere, I did check and it didnt seem to be here yet.
Is there a way, (without use of JavaScript) to get the currently selected item of a DropDownList and say send it off to an ActionLink?
<%= Html.DropDownList("Elements") %>
<%=Html.ActionLink("Add Authorization Element", "AddElement", new {elementGuid = ??? }) %>
The bit I am looking for is something to replace:
???
Thanks,
Ric
Not without JavaScript, no. Of course, it's trivial with JavaScript.
If you want to do both, add JavaScript to the drop down, then put a submit button inside a noscript tag. Users without JavaScript will have to click the button. Users with JavaScript won't see it.
Related
I'm still a beginner at web development. It's not my profession. So go easy.
I started building a rails app today, and realized it would make my application so much better if I could get certain links to display in a separate div instead of a new page, or refreshing the entire page. I'm not quite sure how to search for this, and I keep chasing red herrings with google.
Basically, I have a list in a div on the left side of the page, and when one item from that list is clicked, it should appear in the right div. (Nothing else on the page need be changed)
That's really as simple as it is. Do I need to use Javascript for this? Can I get away with the rails js defaults, or should I be using JQuery?
Is there a way to do this without javascript? I really just need a push in the right direction here, I'm tired of not even knowing how to search for this, or what documentation I should be reading.
Like I said, go easy, and you should just go ahead and err to the side of caution, and assume I know nothing. Seriously. :)
Thanks in advance,
-Kevin
(By the way, I'm developing with Rails 3)
Create your views (along with controllers) to be shown inside the div for each item on the left menu. Lets say we have the following structure now:
Item1 (Clicking on it will fetch:
http://myapp.com/item1)
Item2 (Clicking on it will fetch:
http://myapp.com/item2)
and so on...
make sure you only render the html to be put inside your content div. Should not include <head> <body> etc. tags
In your main page you may have your markup like this >
<div id="leftMenu">
Item 1
Item 2
</div>
<div id="content">
Please click on an item on the left menu to load content here
</div>
Finally, add the following Javascript (you'll need jQuery; trust me it's a good decision).
$("#leftMenu a").click(function () {
$("#content").load($(this).attr("href")); //load html from the url and put it in the #content element
return false; //prevent the default href action
});
You will need JavaScript if you want to avoid reloading the page. You can use link_to for links in your lists, and you'll need to use :remote => true to make it send AJAX requests to the server. The server will need to respond appropriately and supply HTML for your div.
link_to documentation is here: http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-link_to (and admittedly it isn't very useful for AJAX functionality).
The last post in this thread shows one possible solution you could use.
I'm working with ASP.NET MVC 2 and building a simple business app. Here are some of the details:
The app deals with work orders and
has a work order index view. The
view has a table listing the work
orders, and several controls (text
boxes, check boxes, and drop down
lists) to select the criteria for
which work orders to display.
I'm using viewmodels. The work order
index view has a viewmodel with
properties for each and every
control.
I've implemented paging similar to
what is being done in the answer to
this question:
How do I do pagination in ASP.NET MVC?
I'm using LINQ's Skip() and Take() as
demonstrated, and ActionLinks for the
navigation.
If I load the page and don't
manipulate any of the controls, I can
click on the page number ActionLinks
and move around just fine between
pages of work orders. However, if I
change something, my changes are lost
when I navigate to another page.
For example, if I'm on page 1 and
click an unchecked check box, and
then click on the link for page 2,
the second page of results will load
but the check box will revert to its
previous state.
I understand why this happens, but I'm wondering what is the best thing to do from a design standpoint.
Potential solutions I can think of:
Set all the control values as route
values in the ActionLinks. This
seems really nasty, and could result
in very long URLs or query strings. Actually, now that I think of it this wouldn't work without a way to capture the control values.
Since ActionLinks don't post
anything, replace them with buttons.
Again, this seems like a bad idea.
Change the ActionLinks to links that
fire off a jQuery script that does a
POST. I think this is the most
promising option so far. Do many
developers do it this way?
This seems like a common enough problem, but none of these options feel quite right. I wonder if I'm missing something.
Can't you just save the changes back to the database when the user toggles the checkboxes (using jQuery):
$("input[type=checkbox]").click(function() {
$.ajax({
type: "POST",
url: "/ControllerName/SaveInfo?id=" + {id},
success: function(){
alert("Data Saved: " + msg);
}
});
});
In the end, I wound up getting rid of the ActionLinks for the paging, and replaced them with regular anchor tags. The current page index is now stored in a hidden form value:
<input id="page" name="page" type="hidden" value="" />
<p>
<% for (var i = 1; i <= (int)Math.Ceiling(Model.RowsMatchingCriteria / (double)Model.PageSize); i++) { %>
<%--
If the page number link being rendered is the current page, don't add the href attribute.
That makes the link non-clickable.
--%>
<a class="pageLink" <%= i != Model.Page ? #"href=""javascript:void(0);""" : string.Empty %>><%: i %></a>
<% } %>
</p>
Then I added the following jQuery script, which sets the hidden page value and submits the form when a link is clicked:
$(document).ready(function () {
$('.pageLink:[href]').click(function () {
$('#page').val($(this).text()); // Set hidden field value to the text of the page link, which is the page number.
$('form:first').submit();
});
});
Problem solved.
Best bet is to effectively simulate viewstate by "logging" the changes to a hidden field when a user paginates. To do so:
1) Figure out what data you need to capture and a data format to do so in {ie -- an array of json objects}
2) Setup the link that handles the prev/next to fire off a method to collect the "changed" things and stuff them into objects and into a hidden field.
3) When posting the form, parse the hidden field, extract data and profit.
I know this sounds silly but i forgot how to code non-ajax.
Specifically:
I am in MVC
I have a dropdown list with languages.
When a language is chosen i want to reload the whole page with the new language.
This all works but I have to manually refresh the page.
I mean I could call window.location.refresh after i return from the action but i feel like i should be able to do a full refresh. Am i suppose to call submit on a form?
I really feel like i am missing osme extremely easy right in front of my face thing.
I have been doing so many partial ajax updates in my life,i lost my plain old post and reload.
Yea you have to do a form submit, but whats wrong with window.location.refresh?
Normally selecting language for a site is independent of other form submissions, and you can get away with a GET instead of POST. So, in the onchange attribute of your select, you can put:
var lang = ...//get selected language value here
document.location = 'http://mysite.com/' + lang //or whatever your URL scheme is
I need to build something like what gmail does for it's labels... It has a button that when pressed pops up a scrolling list displaying the labels with checkboxes for selection.
I'd like to hear about approaches to do the popup and how to place it right under the button.
Also, I'd like to be able to observe the checkbox select/deselect events and take action, so advice on that part would also be appreciated... otherwise, I guess I'll have to put a form with a submit button and handle the new selections when the user submits.
If the checkbox list is static, you can do all this directly in the rendered action. Otherwise, two approaches are possible:
Use button_to_remote to retrieve an action displaying the popup and also serving the necessary js;
Use button_to_function to retrieve some XML or json (at your option) from an action, with the necessary labels and values for checkboxes, then render the popup.
The first may be easier to do if you're not familiar with all this, while the second is way more efficient, as only data is passed through the asynchronous call, and not markup nor javascript.
About your last question, if (un)checking the checkbox must result in a server side action, prototype_helper provides a convenient observe_field function, to be used like this:
<%= check_box "foo", "bar" %>
<%= observe_field "foo_bar", :url => {:action => :some_action, :controller => :some_controller} %>
If the (un)checking can be managed on client side, you can simply use:
<%= check_box "foo", "bar", { :onclick => "someFunctionToDoWhatINeed(someArg);"} %>
Just two notes:
JavascriptHelper and PrototypeHelper are just this, helpers: they allow you to do some things with a very simple syntax and are great, as long as they are helping; when they are no more, feel free to drop them and go for plain javascript.
I've used prototype for a while, but then I fell in love with jquery; you may want to take a look at it.
Please edit your question or comment my answer if I didn't understand your question and/or was unhelpful.
i want to render a partial within a view. so that when button MORE is clicked everything stays the same just additional characters are shown. in my case the whole article.
<%= #article1.content[0..300] + "..." %>
<%= link_to "more", ....... %>
i dont know what the right methot would be. somehow i have to explain to rails that when button more is clicked it shows me the whole article. maybe i shouldn't use method link_to ..
thank you in advance for your replys
What you're looking for is link_to_remote or link_to_function.
link_to_remote will be fetching the rest of the article from your controller and replacing/appending to a DOM element with a partial via RJS. This allows you to minimize unnecessary data being sent, and facilitates handling users that have javascript disabled.
With link_to_function, the entire article will be served when the page is loaded, but the everything beyond the first 300 characters will be hidden by CSS. This is easier to set up but sends a lot more data, it also relies on the user having javascript enabled.
Without looking at the source the average user probably couldn't distinguish between the two methods.
Which choice you go with is up to you. Sorry, I haven't got time to provide code examples, but the internet is full of them.
try link_to_function, use truncate for part and insert hidden tag with full text, switch them using javascript in link_to_function