I am creating a Spring Boot e-commerce website, and I have a span tag containing the total price so far in cart, and update with JavaScript behind the scenes:
<form method="POST" th:object="${chargeRequest}">
<span class="total">
Total: <span class="total-price">$0</span>
</span>
</form>
and I pass a model attribute model.addAttribute("chargeRequest", new ChargeRequest()); to this page, and ChargeRequest class is defined as:
public class ChargeRequest {
private int amount;
// constructor, setter/getter
// ...
}
The question is: how can update amount in chargeRequest, and pass it back to the controller using Thymeleaf?
th:field is only valid for <input>, <select>, <textarea>, I cannot directly put it to <span> tag
I have tried to pass 2 attributes:
model.addAttribute("amount", new String("$0"));
model.addAttribute("chargeRequest", new ChargeRequest());
<span class="total">
Total: <span class="total-price" th:text="${amount}">$0</span>
<input type="hidden" th:value="${amount}, id="amount", name="amount">
</span>
But I don't know how to update ${amount} such that amount in chargeReqeust can be updated automatically?
Well unfortunately for you, you won't be able to do that with a simple controller. You will need a #ControllerAdvice that will serve as a global controller to be able to update the cart whenever someone adds a product into their cart or remove products from their cart.
In other word, you need a GLOBAL CONTROLLER. This global controller should check the SESSION attribute to allow you to change the amount of total cart and update it every time a change occurs. For example, check this out below.
#ControllerAdvice
public class GlobalCartController{
#Autowired
private HttpSession session;
#ModelAttribute("cartModel")
public CartModel getCartTotal(){
if(session.getAttribute("cart")==null){
//Here you create cart attribute for the session
// then
session.setAttribute("cartModel", cartObjectWithUpdatedTotal);
}
return (CartObjectWithUpdatedTotal) session.getAttribute("cartModel");
}
Note that global controller will be always checked at every time at all routes and don't require a routing, this allows you to use the HttpSession autowired class which allows you to
identify a user across more than one-page request or visit a Web site and to store information about that user.
Cheers
Related
Is it possible with Laravel livewire to change a field in the database when leaving the input field?
You can use wire:model.lazy to achieve an action when leaving (loosing focus) on an input field.
<div>
<input type="text" class="form-control" wire:model.lazy="billingRate">
</div>
class Rate extends Component
{
public $billingRate;
public function updatedBillingRate(){
dd($this->billingRate); // don't forget to use $this to access class property
// persist to database here
}
}
In the above example, whenever billingRate value changes, it will trigger the updatedBillingRate() method.
Please checkout a similar thred on laracast here (https://laracasts.com/discuss/channels/livewire/livewire-how-to-action-the-value-of-an-input-without-a-button)
In my own perspective, you can implement JavaScript event listener when leaving the input field, an ajax request will fire-up to update the database.
I have simple web application written using Springboot and Thymeleaf templates. Report controller receives the data from form and builds the TestPlanReportResponse object which is added as model attribute like this:
#PostMapping("/report")
public String homeSubmit(#ModelAttribute HomeFormInput homeFormInput, Model model, Errors errors) {
final TestPlanReportResponse response = new TestPlanReportResponse(homeFormInput);
model.addAttribute("allData", response);
return "charts";
}
I can work with that data in "charts" thymeleaf template and show the data I need, but I need to send exactly the same object back to controller when button is clicked, but i getting TestPlanReportResponse
object as parameter with nulls set.
#PostMapping("/report/send")
public String sendReport(#ModelAttribute TestPlanReportResponse reportData, Model model) {
//reportData contains just nulls
}
Here is how my button is set in charts template:
<form action="#" th:action="#{/report/send}" th:object="${allData}" method="post">
<button type="submit">Send the report</button>
</form>
So my question is how to send the object back from thymeleaf template? Should i create a hidden input and put there the "allData" object just to send it back? It looks for me like dirty hack. What would be the appropriate way to pass data back? I want to have this app stateless so don't to store the data on a server side.
When I used to work with Spring and Thymeleaf and form, we had the same issue, passing the data back and forth between a form, the template, and different controllers.
And what you suggest is what we did, we used hidden input as dirty as it may look,it was the standard suggested answer, we did not find anything better.
You need to create an input, with a type a value and link it to a field, like this:
<form action="#" th:action="#{/report/send}" th:object="${allData}" method="post">
<input type="hidden" th:value="*{allDataValue1}" th:field="*{allDataField1}" />
//Do this for all your attributes/values that you wish to pass to the controller
<button class="btn btn-info btn-lg btn-block" type="submit">Send the report</button>
</form>
Though, i found this answer, you can try looking into this thread
As per my understanding, model attributes are associated with every request and they can not survive multiple requests, until we add them as flashAttributes.
I have a simple controller method which shows a couple of options to user to select from. However, those options are being attached to thymeleaf template using model attributes.
<div class="input-group mb-3" th:each="ingredient : ${recipes.ingredients}">
<div class="input-group-prepend">
<div class="input-group-text">
<input aria-label="Checkbox for following text input" name="ingredient"
th:value="${ingredient.name}" type="checkbox">
</div>
<input aria-label="Text input with checkbox" class="form-control" disabled
th:value="${ingredient.name + ' ' + ingredient.price + 'Rs.'}"
type="text">
</div>
assume "recipes" as model attribute here, which was injected to modelMap inside the controller.
when bean validation fails, below line exectutes.
if (errors.hasErrors()) return "selectItem";
and selectItem template is re-rendered, but whatever model attributes I have set inside previous controller vanishes.
I have solved this using a #ModelAttribute method inside the same controller to set model attributes for every HTTP requests for the specific controller(until it is not in controllerAdvice for global effect).
I am being confused if I am on right way || is there any elegant way to achieve this.
Setting Model attribute for every request is kind of overhead, when I want them to be available for handful of request mappings.
When you say:
selectItem template is re-rendered, but whatever model attributes I
have set inside previous controller vanishes.
You mean that when the page reloads due to validation errors, your model attributes are no longer existing and Thymeleaf probably returns an error, because it cannot find them, correct?
If this is the case, then you have to manually prepare the same model attributes within the if statement (i.e. adding them to your MapModel):
if (errors.hasErrors()) {
map.addAttribute("recipes", recipes);
return "selectItem";
}
Alternatively, if you need this model attribute also on other pages in your controller, you can reduce code duplication by declaring a method with the ModelAttribute annotation, which will add this attribute to all models in your controller:
#ModelAttribute("recipes")
public Recipes loadRecipes() {
// get list of Recipes
return list;
}
I'm trying to add an attribute to an HTTP session with thyme leaf, but I can't. I had a "Project" object and I need to pass it to the controller. I had a form in the page, so I've tried this, but it doesn't work:
<input type="hidden" th:attr="${#session.setAttribute('proyecto', '${proyecto}')}"
The controller receives the attribute proyecto but the value is "${proyecto}", not the content of the project object
Send the value using a form and then set the session attribute in your controller.
HTML
<form th:action="#{/newProject}" th:object="${newProject}" method="post">
<input th:field="*{id}"></input>
</form>
Controller
#RequestMapping(value = "/newProject", method = RequestMethod.POST)
public String addProject(HttpSession session, #ModelAttribute("newProject") Project project) {
session.setAttribute("proyecto", project);
return "/newPage";
}
This is just example of course. You would need to add all the project fields in your HTML.
sorry for a dumb question but i can't understand quite what happens, and if it is what i suspect.. well i am really at a loss.
i am using spring boot + thymeleaf + materialize css to show and validate a form.
now what i don't meet in many examples that i see is this case:
some form fields are pre-filled and should seem disabled to the client, showing their pre-filled values. this pre-filling takes place in the controller, while i handle some other request, and redirect to this view
i am binding a pojo to the form using th:object like this
<form id="register_form" action="#" th:action="#{/showform}" th:object="${userInfo}" method="post">
<div class="input-field">
<label th:text="#{label.surname}" for="surname"></label>
<input type="text" th:field="*{surname}" id="surname" th:attr="value=${userInfo.surname}" />
</div>
<div class="input-field">
<label th:text="#{label.name}" for="givenname"></label>
<input type="text" th:field="*{givenname}" id="givenname" th:attr="value=${userInfo.givenname}" disabled="disabled" />
</div></form>
and getting it in the POST handler of the controller like this:
#RequestMapping(value = {"/showform"}, method = RequestMethod.POST)
public ModelAndView submitFormPage(#ModelAttribute("userInfo") #Valid UserInfo userInfo,
BindingResult bindingResult, RedirectAttributes redir)
{
ModelAndView mview = new ModelAndView();
if (bindingResult.hasErrors())
{
// show form again with error messages
mview.addObject("userInfo", userInfo);
mview.setViewName("/showform");
}
else
{
// ...
}
return mview;
}
RedirectAttributes is there for some other reason. As you can see, there are two elements on a form, and first one is enabled, and the second disabled.
Their values are populated correctly with pre-filled values from the POJO i pass to the view via the ModelMap. i can also trace it in the GET handler.
but the ModelMap i get back from the view contains the aforementioned POJO with NULL values in place of the elements that are bound to the disabled controls. i would expect them to be populated by the contents of the value attribute, even though those controls are disabled. the enabled controls carry their values alright.
or is it just that disabled controls simply are not included in the postback? if this is the case, how would you suggest me to do it? some suggested adding an obscure CSS that would "fake" the behaviour of a disabled control. or have i missed something in the general wiring?
i think with horror of possible workarounds - but i must be doing something wrong.. th:attr was one of the workarounds i tried, but it doesn't seem to do the trick. i also tried using th:id and th:disabled but it didn't help either.
There is a misunderstanding here I think about the use of disabled.
A readonly element is just not editable, but gets sent when the
according form submits. a disabled element isn't editable and isn't
sent on submit. Another difference is that readonly elements can be
focused (and getting focused when "tabbing" through a form) while
disabled elements can't.
More detailed comparison
So to answer your question: you should opt for readonly if you want to bind your attributes to your pojo and still the user can't edit them.