I have 2 gsp's say, "a.gsp" and "b.gsp".
"a.gsp" have combobox, from which user can select options.
My question is that, if the user shift to "b.gsp" and then come back to "a.gsp", the combobox selected option should be still there.
How to achieve this ?
You can do multiple things to achieve this. Depending on your requirements you may:
Use javascript and cookies.
Pass the value selected in the combobox into the controller when you naviate to b.gsp and into a hidden field in b.gsp, but then you have to pass it back to the controller once more when you want to see a.gsp.
Pass the selected value inside session/flash scope
From your question it sounds like you are not fully embracing Grails' MVC architecture and using controllers correctly to prepare data and pass structured data through to your view.
To begin with, rename your controller actions and views to something meaningful rather than a,b. Even if just for testing a small sample, as taking shortcuts can lead to long term bad habits...
Secondly, if you are using a tag then you would use the value attribute to indicate what should be selected.
Read about the tag and its attributes here : http://grails.org/doc/2.1.0/ref/Tags/select.html
Give us more details and perhaps we can help.
Thanks for the clarification, so I'm assuming that there could be any number of ways a user might leave the current a.gsp page and come back, but whatever happens you want the browser to remember the selected option. In this case I would use the jQuery cookie library, its very small, won't impact performance as you're doing very litte work and should be very quick for you to setup.. See: https://github.com/carhartl/jquery-cookie
Set a cookie in an onChange handler based on your selects val() value.
When your page loads (document ready), if you get a value when reading the cookie, then try and set the select value.
Related
I have a simple view that displays some customer details in a list. The user can filter down the list using drop downs and text boxes to show results they are interested in and then JQuery/AJAX is used to return a partial view and update the list. For each item in the list there is an edit button which takes the user off to a different action to edit that specific item. When they save or cancel the user is directed back to the customer details page but the filters they had applied have obviously reset back to default. I was wondering what the standard way would be to tackle this seemingly common problem in the MVC world?
Thanks.
As HTTP is stateless protocol , it's your responsibility to remember the state of the page. One of the way we do is show the additional detail on clicking the Edit button on the same page in popup . It will solve the problem in case you are ready to make the design change.
Otherwise you have to use the standard state management technique , like Session or Cache on the Server to remember previous search state or you can append some key value in the URL it self and when user cancel , recollect the state from the URL query string .
One more way if security is not concern is using the Cookie to store the previous selection on the client machine if it is very specific to user.
Just use Session to persist their filters. It tends to be overused by inexperienced developers but the situation you describe is pretty much exactly what it is for.
One way is to fake the update of current row.
Consider, You clicked a delete button to delete the row.
Now with jQuery-
$.get(url,data,function(data){
if(data.success){
$('row').fadeOut(300,function(){
$(this).remove(); //<--- This is what I mean
});
}
});
Here you have removed the row on the basis of Json result and your page didn't need any refresh.
Also as in your case, Just load the edit Partialview at the same page by managing some space.
You can do this at least.
On Telerik demo site we can see an example of how to implement kind of functionality: "check all checkbox in a grid's column". But in my case it has 2 disadvantages:
It didn't check all checkbox on all pages.
It didn't save a state of checkboxes on different pages.
Is anybody know how to resolve these issues? Thanks in advance.
As long as I know there's no built-in functionality to do so. The same problem happens when you select records on page one and change to page two, you loose whatever you selected before.
To achieve that functionality you have 2 options (I've used both on previous projects)
1) On each check make an Ajax call to one of your controllers and store whatever you selected on a Session Variable (This can be inefficient if you have a lot of records)
2) Create a javascript variable and store your selections there, and send back to the controller using a json variable or a comma separated values string
As I said, I've used both approachs so it depends on if this works for you or not
Hope it helps
I can't test this, so I'm not 100% sure, but looking at Telerik's example, one reason it's not persisted is because every "page" of the grid requires a postback, and in the controller action result method, they aren't passing in the model (or view model) for the items that are bound to the grid, they're only returning that list of items back to the view, so it will never "save" which items are checked/selected and which ones aren't. You should be able to get around this by making your view model a parameter into the HttpPost action result method and then passing that list back to the view after the post so that it retains which items are selected instead of creating a new one. This won't solve the issue with not selecting all the items, but it should at least retain which ones are selected throughout the pages. I think the reason for it not working with all items is it can only select the ones that are actually being displayed at the time. You may want to do a post (or ajax) to select "all" items.
One of the major reasons for using paging in grids is so that you don't have to retrieve all of the data from the data store and generate a lot of HTML to push to the client.
It's been my experience that most users understand that a "select all" check box only checks the items on the current page. I've not seen a site where checking such a check box would actually check all records, even those I can't see.
If you have an action which will affect more than the current page of records, I would suggest that you add a button which clearly indicates that the action will affect all records, then send a command to your data layer which will perform that action. This will perform better (you don't have to send a potentially long list of ids across the wire) and allow users to understand the repercussions of their action.
I am trying to conceive of a way to store a list of selected items to the session, for later use. I've googled and read examples for 2 hours now, and haven't found any examples that work.
The basic idea is this. User sees a list of items to act upon. User selects a number of them. User chooses action to perform. Controller takes list of selected items, and begins to act on them.
Am I thinking about this wrong? It makes sense to me to use an Ajax action to store the 'select/unselect' action on the session object. I really don't want an entire database object to handle this. I just want a simple list of selected objects. In classic ASP, I'd just have reacted to the selected items in a form post, but that doesn't seem right in asp.net mvc....
How do I construct this behavior (with or without the Ajax, but preferable without the DB access)?
I don't get it, why not bind directly an array of bools or something directly to your view's list of checkboxes? You can get them as parameters in your controller function and act upon them directly, with no middleman, they'd just be another POST value.
Or even better when you send in your list of items as part of your model, make them a structure that has a bool selected=false field that is bound to the checkbox next to the label, and you'll get the results back in your model directly.
I am currently binding an IEnumerable collection to a ListBoxFor, which works as expected, sending the currently selected values on POST. However, I need to send all the values instead (essentially any value in a given ListBoxFor I consider to be required, whether selected or not). How would I go about doing this?
(I can probably rig something up in jQuery where, on-submit, it manually selects all the elements in a box, but was wondering if there was a better way.)
If you want to continue using normal browser form serialization on submit, write a javascript function to fire right before the submission (hook into an onclick event or something) which iterates through the list box control and concatenates the desired values (perhaps comma-delimited) and places it in a hidden field. The value of that hidden field will be submitted normally and you can parse the individual values from it on the server side. It's still some manual work, but you avoid messing with GUI state (i.e. selecting all desired list box items) which I agree is something you don't want to do.
I am displaying 3 or more versions of a form. One version is an edit form to edit all fields. A second version will be a read only version of the same form which will be used to show all the same fields but with all fields having readonly="true" on the client side so that the user cannot enter data. The readonly fields need to use a different css style. This is to display archived data. I am already hiding the submit button so they can't submit but I want the form to look like it is readonly. A third version will have some fields readonly and some editable for a particular class of users that has limited editing privileges.
I am using ASP.NET MVC 1.0. How do I modify all (or a subset) of the fields displayed so they are readonly. I would like to iterate through the collection of fields in the controller and set them all to readonly and also set the correct css class. I don't want to have to put an if statement on every field in the .aspx file (there are 40-50 fields) and I'd prefer not to have this on client side so I can prevent users from modifying javascript/html to edit things they are not supposed to.
TIA,
Steve Shier
Keep in mind that even if you set the tags as readonly on the server side, users can still change them through a variety of means, and whatever the value on the form is before it gets sent back to you.
Certainly the easiest way is client-side with jQuery:
$(function() {
$('input, select, textarea').attr('disabled', 'disabled');
});
Or, you could do it in your View, but it's ugly. Off the top of my head, you would need some sort of bool passed into the View (via ViewData I suppose), and check that on each Input to see if you should add the disabled attribute. Not my idea of fun...
I would have different views that correspond to your states and then choose the view depending on which state you are in. You could also implement it with partials, breaking down the pieces so that you can easily include editable or read-only versions of the different sets of elements. The read-only view, then, need not even include a form element. You could also present the data in spans, divs, or paragraphs rather than as input elements.
Note: you'll still have to check whether the current user has the ability to update/create data in the actions that process form submits. Just because you limit the ability to view data in a read-only format, that won't stop someone from crafting a form post to mimic your application if they want. You can't rely on hiding/disabling things on the client to prevent a malicious user from trying to enter/modify data.
I usually use partial views to represent forms and/or parts of forms.
I can think of two simple ways to do what you need (as I understood it):
<% Html.RenderPartial(the_right_partial, model); %> where the_right_partial is either a value passed from the controller or a helper (in which case, the_right_partial(something));
pass a bool or enum paramether from controller representing editability and then using a helper to obtain the right htmlAttributes, like:
<%= Html.TextBox("name", value, Html.TheRightHtmlAttributesFor(isReadableOrNot)) %>;
There may be other ways, like creating new helpers for input fields which accept an additional isReadableOrNot arg (but it seems an overkill to me), or like mangling the html/aspx in some odd (and totally unreadable/unmaintainable way), but I'd not suggest them.
Notice that using html attributes like disabled is client side, and with tools like firebug it takes just two seconds to change them.
Others have already said it, but I also have to: always assume that the user will do his/her best effort to do the worst possible thing, so check the user rights to modify stuff on server side, and consider client side checks as a courtesy to the user (to let her/him understand that the form is not supposed to be edited, in this case).
Since I am trying to use a single partial for the different states of the form, I am thinking I will create helper functions which will display correctly based on the state and the user. The helpers will use a dictionary of fields that will indicate under which condition the field is read only. I will still have server side checks to make sure data is valid and the user is authorized to make changes.
Thanks for all of your ideas and help.
Steve