I'm writing a Selenium test for my Rails application, and sometimes run into the "Stale Element" exception. It's easy enough to perform another lookup on the element before operating on it, but to keep my code DRY, I'm wondering - is there any sort of method available on Selenium::WebDriver::Element objects to "refresh" stale references?
EDIT: To clarify, I'm asking if there's some shorthand method for doing another find_by_xpath (or id, etc.) call with the same parameter being passed. It's perfectly functional, just not as terse as some sort of "refresh" method would probably be.
If I understand correctly, you are asking about some sort of "refresh" or "update" method on a WebElement instance.
Unfortunately, there is no such thing in selenium by definition. According to the relevant issue WebElement refresh() or getBy() needed:
WebElement object is a proxy, a representative of a DOM element. When
DOM element is destroyed by the browser, WebElement is marked "stale"
and can't be used anymore.
If you have a similar DOM element on another page, you can obtain it
with findElement, and Selenium will create a new WebElement object
(a proxy) for this new DOM element. Your old WebElement object will
remain stale because underlaying DOM object is destroyed and never can
be restored. Similarity is not equality.
I would recommend store element-specific locators, but once the page refreshes, you would still need to "refind" the element by the locator.
The only thing available is keeping track of your application state when writing your Selenium code.
Did you perform an action that refreshed the DOM? Then you need to perform another findElement call to get a new instance of the element you want to interact with next.
Otherwise, write your own method findElementByXpath in a Utility class that tries to find an element, catches a StaleElement exception and retries.
I am going to describe my case which is similar:
I tried to find a table cell with some value by doing this:
Get all table rows
For each row - get a collection of the columns
For each column - seek the value
One day, I had a case with too many results in the table. So, I programmed the loop to click the "Get next page" link/icon.
Simple? no! when the program clicked the "next page of the table" link, the WebElement which pointed to the table was not usable, I received the same error as the author of this question: StaleElementReferenceException
What I did is:
Get the XPATH of the table first, and then I changed the loop so if all the rows were scanned, and he value was not found and if the next icon is enabled:
Click the next page of the table.
Update the WebElement to re-point the table.
I hope I am clear.
Related
There are lots of similar questions to this on SO but none of them have really provided an answer to my particular case. Or at least I can't figure it out!
I have a form with an autocomplete field which is used to populate other fields if a record exists.
I have found that some users type in a value and click to the next cell using the mouse and therefore do not make a selection from the autocomplete list. It's possible that they have typed a value with a matching record in the input field and in that case I want the form to be populated with the appropriate data. Or if it doesn't, then clear the form.
The only way I can think of to check the value exists in the database is to use the change event to make an ajax call to retrieve the data but that doesn't seem like a very elegant solution and I'd be very surprised if there isn't a better way to do this since it seems to me that this would be a very common scenario...
Is there a way to retain the autocomplete array and check it against the input value in the change event? Or how else can I do it?
What you can do is stash away a copy of the data returned in the ajax call's success callback.
You can then add a blur event handler to the autocomplete input, so it'll be called whenever the user clicks away to the next field. In the event handler, check the stashed ajax data, and if there was only a single possible match, use that to populate the input.
I am trying to conditionally suppress a widget from its driver. I basically have logic that if met, should display the widget and if not, should suppress it. The widget loads properties from the current page content item, and based on some properties should display or hide. I've got all the logic working, the only part left is suppressing the actual output.
I've tried returning null from the driver, however this simply outputs an empty widget (with its wrapper). How do I completely remove the widget from view?
Finally, the zone that this widget is placed in should suppress if none of the conditional widgets display.
Is this type of flexibility possible in Orchard? Preferably from my custom module not my theme, I'm trying to separate functionality from styling.
EDIT:
Here is the context of my situation and what I am trying to accomplish. I'm sure there is a much cleaner way to do this within Orchard than how I have naively designed it the first go-around: My client's copywriters tag pages as they see fit (using the Tags module/part). I have created 2 custom content types, "Testimonials" and "Offers", both with tags themselves among other properties [these are managed by a different team of copywriters].
On most "inner pages" of the website (I'm using a layer to determine the appropriate pages), the page's sidebar gets a "Testimonial" widget and a "Offer" widget. These widgets both operate the same, although independently of each other:
They grab the tags of the current page, then pull a random [Testimonial|Offer] that has any matching tags as well. There are 4 cases that can happen given any inner page: a testimonial is displayed and the offer is hidden (testimonial tag matched, offer tag didn't), the testimonial is hidden and the offer is displayed, both the testimonial and offer displays, and finally neither displays. The first 3 use cases are working great, the 4th is what I'm having difficulty with, as the sidebar [zone] still displays even if both widgets do not (returning null from their respective drivers).
A bit of context about widgets: widgets are supposed to be pieces of contents that are visible on some or all pages of the site, and that provide information that is not directly related to the main content item on the page (if there is such a thing).
As a consequence, what you are describing should not be implemented as widgets (all that you had to do to make it work attests to that further), because they are really part of the content item. Instead, you should have implemented a part or a field. You can then simply place the shape for this part of field, using placement, by specifying a top-level zone: <place the_shape_name="/the_zone_where_you_want_it:1"/>
Unfortunately I've had to use a bit of a hack so that I could move on with the project as I'm under an aggressive deadline, but if there is a better method and/or solution I'll test as I get the chance and mark as the answer.
To get it to work, I overwrote the Widget.Wrapper.cshtml file within my theme. There, I assigned a variable to the Display(Model.Child) call, and if the result is an empty string simply return. This removes any empty widget wrapping tags. (I personally feel Orchard should behave this way by default):
var child = Display(Model.Child);
// -- NOTE: shape tracing breaks this logic!
if (string.IsNullOrWhiteSpace(child.ToString())) {
return;
}
Then simply replace the #Display(Model.Child) between the header and footer with #(child)
I then added the following method to my Layout.cshtml file.
Func<dynamic, IHtmlString> CollapsableZone = x =>
{
var display = Display(x);
string zoneName = x.ZoneName;
if (string.Equals(display.ToString(), string.Format("<div class=\"zone zone-{0}\"></div>", zoneName.HtmlClassify()), StringComparison.CurrentCultureIgnoreCase))
{
return new HtmlString(string.Empty);
}
return display;
};
Simple function that assigns the display call to a variable, checks if it is an empty zone tag, and returns. I then create variables for each zone assigned to the value of the function above. I replace all the #if (Model.ZoneName != null) with #if (!string.IsNullOrWhiteSpace(zoneVariable)), and replace the calls to #Zone(Model.ZoneName) with #(zoneVariable).
This is working for the time being. It is quite a hack and brittle solution but I've had to move on to other things.
let's assume i have the following structure:
pageA.xhtml - Here we can select an item which will be needed within pageB and pageC but not in pageE.
pageB.xhtml - Here we use the Item which was selected from pageA. We
also have a selectBox and some Buttons on this page.
When selecting something from the selectBox some Buttons will be deactivated and some Text can be displayed.
(when refreshing this page we want the same state again). pageB includes
pageD which lists some stuff. Now we can navigate to pageC.
We also create some objects which are only relevant for pageC but not for other pages.
pageC.xhtml - here we get the object from pageB and depending on some User input we modify it and when we press apply we come back
to pageB which displays
our changes. From pageB we can press save which will save the changes and pageD (which is included in pageB) will be
updated.
pageD.xhtml - just lists some stuff. (will only included within pageB)
pageE.xhtml - This page will start something completely differend and does not need the input from pageA but you can navigate directly
to pageC. In this case pageC has to
hide some things.
I hope the example is somehow clear. Actually i just made it up to make my question a bit clearer: I want to know what the best practises are to pass data between different pages and save the actual state (also have the same state when coming back).
Also how to reset/clear data which are needed in some pages but not in different ones.
For example some data will be needed for several pages but some only within nested pages (in an optimal world the data within the nested pages should be cleared when leaving them)
Of course i could save stuff i need into the session, but then i have to be careful to remove those stuff again when i don't need it anymore. JSF and CDI support Conversations. But the problem here is that it is not possible to have nested conversations. Of course i also could pass everything with request parameters .. but in this case i have to be careful if i have ajax requests within my page (i guess i would have to send always all parameters).
I'm using JSF 2.0 with CDI. Any answer will be appreciated. Sadly i cannot provide any code example .. so i hope i was able to express my self clear enough.
greetings kukudas
You could create a new CDI scope or recreate the ViewScope in CDI. Take a look at CODI conversations as well.
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.
Here's a simple problem: users want to edit products in grid-like manner: select and click add, select and click add... and they see updated products list... then click "Finish" and order should be saved.
However, each "Add" have to go to server, because it involves server-side validation. Moreover, the validation is inside domain entity (say, Order) - that is, for validation to happen I need to call order.Add(product) and then order decides if it can add the product.
The problem is, if I add products to order, it persists changes so even if users do not click "Finish" the changes will still be there!
OK, I probably shouldn't modify the order until users click Finish. However, how do I validate the product then? This should be done by the order entity - if product is already added, if product does not conflict with other products, etc.
Another problem, is that I have to add product to order and "rebuild view/HTML" based on its new state (as it can greatly change). But if I don't persist order changes, the next Add will start from the same order each time, not from the updated one. That is, I need to track changes to the order somehow.
I see several solutions:
Each time the user click Add, retrieve order from database, and add all new products (from the page), but do not persist it, just return View(order). The problem is I cannot redirect from POST /Edit to GET /Edit - because all the data only exists in the POST data, and GET lose it. This means that Refresh page doesn't work in a nice way (F5 and you get duplicated request, not to mention the browser's dialog box)).
Hm, I thought I can do redirect to GET using TempData (and MvcContrib helper). So after POST to /Edit I process business logic, gets new data for view, and do RedirectToAction<>(data) from MvcContrib that passes data via TempData. But since TempDate is... temp... after F5 all the data is lost. Doesn't work. The damn data should be stored somewhere, this way or another.
Store "edit object" in Session with the POST data (order, new products info). This can also be database. Kind of "current item - per page type". So page will get order ID and currently added products from this storage. But editing from multiple pages is problematic. And I don't like storing temp/current objects in Session.
Marking products as "confirmed" - if we do /order/show, we first cleanup all non-confirmed products from the order. Ugly and messy logic.
Make a copy of the order - a temporary one - and make /Edit work with it. Confirm will move changes from temp order to persisted. A lot of ugly work.
Maybe some AJAX magic? I.e. "Add" button won't reload page but will just send new + already added products to server, server will validate as order.Add(products + newproduct) but will not persist changes, will just return updated order information to re-build the grid. But Refresh/F5 will kill all user-entered info.
What else?
Is this problem common? How do you solve similar ones? What's the best practices?
It depends a lot on how you implement your objects/validation, but your option number 5 is probably the best idea. If AJAX isn't your thing, you can accomplish the same thing by writing the relevant data of already-added-but-not-saved entries to hidden fields.
In other words, the flow ends up something like this:
User enters an item.
Item is sent to the server and validated. The view is returned with the data entered by the user in hidden fields.
User enters a second item.
Item is sent to the server, and both items are validated. The view is returned with the data for both items in hidden fields.
etc.
So far as F5/Refresh killing entered data... In my experience this isn't too much of a problem. A more pressing concern is the back/forward buttons, which need to be managed with something like Really Simple History.
If you DO want to make the page continue to work after a refresh, you need to do one of the following:
Persist the records to the database, associated with the current user in some way.
Persist the records to session.
Persist the records to the query string.
These are the only storage locations available that persist through both redirection and refreshes.
If I were you, I would come up with something which resembles option 5. And since you say that you are comfortable with Ajax you can try this. But before you do this, you should move your validation logic outside the Order.Add() method. Maybe you can move it to another public function called Validate() which returns a bool. And you can still call the same Validate() in the Add() method, thereby doing the necessary validation before you add the order.
Try to do the validation on the client side. If you are using jQuery, you can use the jquery validate plugin. But, if this is not possible for some reason (such as when you need to validate stuff against a database). You should do your validation on the server side and just return a JSON object with the 'success' boolean flag and an optional message, just a way to mark that the data is valid. You would allow the user to add a new product only if the previous Order was valid.
And when the user hits finish send the product to the server and do the validation again, but persist the order in this round-trip.
Now, If I had a complete say in this, I wouldn't even go to the extent of doing validation whenever a product is added/edited. I would just do the validation whenever the customer hits finish. That would be the simplest solution. But, maybe I am missing something.