I have a Person class with two properties: name and address. I want to build a GSP page which allows for 10 users to be created at one time. This is how I'm implementing it and was wondering if there is a better way:
First, make 20 text boxes in the GSP page - 10 with someperson.name and 10 with someperson.address field names (make these in a loop or code them all individually, doesn't matter).
Second, process the submitted data in the controller. The someperson object has the submitted data, but in a not-so-nice structure ([name: ['Bob', 'John'], address: ['Address 1', 'Address 2']]), so I call transpose() on this to be able to access name, address pairs.
Then, build a list of Person objects using the pairs obtained from the previous step and validate/save them.
Finally, if validation fails (name cannot be null) then do something... don't know what yet! I'm thinking of passing the collection of Person objects to the GSP where they are iterated using a loop and if hasErrors then show them... Don't know how to highlight the fields which failed validation...
So, is there a better way (I should probably ask WHAT IS the better way)?
You should use Grails' data-binding support by declaring a command object like this
class PersonCommand {
List<Person> people = []
}
If you construct your form so that the request parameters are named like this:
person[0].name=bob
person[0].address=england
person[1].name=john
person[1].address=ireland
The data will be automatically bound to the personCommand argument of this controller action
class MyController {
def savePeople = {PersonCommand personCommand->
}
}
If you call personCommand.validate() it might in turn call validate() on each Person in people (I'm not sure). If it doesn't you can do this yourself by calling
boolean allPersonsValid = personCommand.people.every {it.validate()}
At this point you'll know whether all Person instances are valid. If they are not, you should pass the PersonCommand back to the GSP and you can use the Grails tags:
<g:eachError>
<g:hasErrors>
<g:renderErrors>
to highlight the fields in errors. If you're not exactly sure how to use these tags to do the highlight, I suggest you run grails generate-all for a domain class and look at the GSP code it generates.
Related
I have a grails application that takes user input (create page/method), the user then clicks a Save button (save method that executes service) and then the results are displayed (list method) on a page, for example http://localhost:8080/myApp/myclass/save.
The users would like each results run to be saved to a unique URL so they can share it, bookmark it, save it later, whatever. I have NO idea how to go about this and google searches turn up little to nothing.
For example an application run would result in the data being displayed at http://localhost:8080/myApp/myclass/systemname/datetimestring/someuniquedata/
Is this even possible? Any pointers GREATLY appreciated.
EDIT
Here is my urlMappings contents.
class UrlMappings {
static mappings = {
"/$controller/$action?/$id?"{
constraints {
// apply constraints here
}
}
"/" {
controller = "api"
action = "create"
}
"500"(view:'/error')
}
}
When I display the results it's done through the list method shown here.
def list(Integer max) {
List<Api> api = Api.findAllBySessionId(session.id, [sort:'dateCreated'])
api = api[-2..-1]
[apiInstanceList: api, apiInstanceTotal: api.size()]
}
So I have the unique session ID. How do I need to modify "mappings"?
Every domain object that you're saving will have an autogenerated ID (assuming you're using GORM, which is definitely likely). It sounds like all you're asking for is a /show/id page where you can access a particular object via ID.
A url mapping for "/$controller/$action?/$id?" is a pretty straightfoward way to handle this, and is provided by default (and used by scaffolded controllers also).
If you'd rather not use an autogenerated ID (maybe you're moving objects from one database to another, or updating the ID for some reason?) you can consider using java.util.UUID.randomUUID() to generate a random, unique identifier and save that as a field on your object. You could then use .findByUuid with the input parameter.
I have a gsp form which displays the list of employees with the details (ie., Employee Name,Designation,Department,Status). All these columns are sortable. After calling a specific action in my controller class (ie., Changing the status of the employee from active to inactive and vice versa) the sorting gets disturbed. I am using the following code to sort while retrieving from DB
String strSort = params.sort ?: "empId";
strSort += " "
strSort += params.order?: "asc";
Is there any way I can retain the sort order which was there before posting a "Status change" action? If it is how it can be achieved?
As suggested by rvargas, it is possible through a variety of methods. queuekit plugin isn't released properly as yet so you could clone grails 3 / grails2 branch depending on which it is you are working with and also clone the test site to go with it to mess with this concept within the plugin:
In short You need to separate out your search feature and you can do this via a session value or send it as a subset list iteration.
I decided to not use sessions. Then when I click delete The bean is bound back in with the request sent (which be the id to delete)
At the very end it relists so no need to do any other here:
The most important bit being when I call the ajax reloadPage or even further postAction used by delete function is that I serialize search form. The actual search object is kept in a tidy manner here
But if this is too complex then in the very controller link the session search was commented out. I think you could just enable that forget all this complication and have a searchAgain() feature which renders the _list template like it does if it is xhr in my controller and rather than binding bean it binds the session.search map instead and if you did go down this route you probably want to change from g:render to g:include action="searchAgain"
Hope that helps you understand better
I can think of two ways to do it:
Pass your sort and order parameters to your action and send them back
with the result.
Store in session both parameters every time you update them.
To store and retrive from session use something like this:
private DEFAULT_SORT = 'myDefaultSort'
def myAction() {
if (params.sort && params.sort != session.getAttribute('sort-' + actionName)) {
session.setAttribute('sort-' + actionName, params.sort)
}
params.sort = session.getAttribute('sort-' + actionName)?:DEFAULT_SORT
...
//Your existing logic
}
If you receive a new/different sort parameter you save it into session. Then you try to load existing parameter from session, if you dont have any value stored, you get a default value.
so I am working on a web app when the users click on create on the list screen, it takes them to a page where they have to enter some information and then they click on "next" and it will take them to another gsp page where they have to enter data for two domains but none of the data are stored yet in the tables but when they click on "create" button, everything get stored in the database
I was looking for examples but couldnt find any.
I know how to call the record and edit it since all the domains or the tables share id number so I can use it to retrive data. but my problem is when I transfer from the first gsp screen to another I want to save the instance and then when the users click on create, data goes to the three tables
any idea how to do that? I am still beginner and trying to learn
thank you
It sounds kind confusing what you wanna do and I am not sure I completely understood. Because you want to change the whole page, and yet, not to lose those previous answers, right?. Is there a specific reason why you want to do this?
I believe you could sent all the information from the first gsp to a controller and save everything in the "session" (e.g session.name = params.name, session.age = params.age), redirect/render the other gsp and later on, you get the info back from the session plus the info that just came and save everything. This is probably not a very good solution, but this is the only way I figured this out.
:)
Just an idea, I haven't used it until now, but I will some day in the future to modify the dialog-flow in my current application...:
Wouldn't that be a good example for the webflow-plugin?
This is what command objects are used for. Any time you have a collection of data that you want to collect in a form and then "generate" multiple domain objects from, then this is the way.
The idea is to create a single class that has all the information that you want to collect on the form. You post the filled form data back to the controller save action which then validates that the data is complete using the command object constraints. Once you are happy with everything, you then use the data in the command object to create/update your domain objects.
We consider the use of command objects a Grails best practice. You can provide custom validation support in the command object that looks for and validates relationships in the data that are difficult to do with the domain objects. We often write factory methods in the command class that produce a new or updated domain object, making it very convenient for unit testing.
See the "Command Objects" section of the "Web Layer" in the manual for details. In Grails 2, command objects are classes with the #Validateable annotation and in Grails 3 they implement the Validateable trait. If you declare your command class as an inner class in the controller, then it is automatically validateable. We've found that we prefer to declare them in src/groovy rather than as inner classes because they are easier for someone unfamiliar with the code to find.
So amongst all of these answers you have your answer but in all honesty I think it is well beyond your own comprehension at this point.
Assuming you have this example as a form
http://code.runnable.com/UevQr3zfd_oaAAGn/jquery-ui-tabs
On tab 1 you have
Name
Age
On tab 2 you have
Address
Postcode
Then you have two domain class
Class User {
String name
String age
Address address
}
Class Address {
String address1
String postcode
}
So a user has name age and also binded to address, whilst address has address1 and postcode
now your controller action
def save(MyBean bean) {
Address address = new Address(bean.loadAddress()).save()
User user = new User()
def userMap = bean.loadUser()
user.age=userMap.age
user.name=userMap.name
//The above object that got saved first
user.addresss=address
user.save()
render "hopefully this should have saved it as expected"
}
In src/main/groovy/yourPackage/MyBean.groovy
package yourPackage
import grails.validation.Validateable
Class MyBean implements Validateable{
String name
String age
Address address
String address1
String postcode
//Now declare your constraints like your domainClass add validator where required to add additional verification/validation to your objects sent back
//This will return all the objects required as a map to save address domain class
protected Map loadAddress() {
Map results=[:]
results.with {
address1=address1
postcode=postcode
}
return results
}
//this will return the user object
protected Map loadUser() {
Map results=[:]
results.with {
name=name
age=age
}
}
}
Other fairly complex validation bean examples:
PhotosBean CustomerChatBean ScheduleBaseBean
Other points of reference:
As I say I think as a beginner this may take you a while to get your head around but hoping with what is provided it will become a lot clearer now
E2A
It is really complicated!! can I have two gsp screens instead of jquery tabs
That doesn't make much sense.
You can have two actions which one just passes params onto 2nd gsp ?
So
def TestController {
def index() {
render view: page1
}
//where page 1 is the first form and submits to action2
//action2 picks up parmas from page1
def action2() {
render view: page2, model:[params:params]
}
}
in page2.gsp you have
<g:form action="action3">
<g:hiddenField name="originalName" value="${params.originalValue}"/>
<g:hiddenField name="originalName2" value="${params.originalValue2}"/>
<g:hiddenField name="originalName3" value="${params.originalValue3}"/>
Then your actual form content
The problem with doing this this way, is does action2 need to verify params received from page1 ? if so it needs to either render original page or page2 depending.
Once submitted to page2 the hiddenFields can be tampered with by end user so what was validated may be invalid now. You will need some form of a way of revalidating all those again.
Using validation methods above you could just call the validate() functions or maybe build some md5 check of initial values vs what is now sent from page2.
Either way if you don't care about validation and just want to see it work then above is the simplest way.
can I have two gsp screens instead of jquery tabs
in page1 you can just do <g:include action="page2"> and include a 2nd gsp within first but in all honesty page 1 could have just contained both actions in 1 page. which is why it don't make sense
I trying to use Grails Scaffolding to throw a quick CRUD application together around some legacy database tables (see this previous StackOverflow question for the saga thus far). I am now past the worst of the issues, and have a functioning CRUD app, but there is one problem remaining with general usability.
Many of my domain objects have foreign-key associations with other domain objects. A Contact belongs to an Owner, etc.
However, on the CRUD pages for Contact, I don't want to see the actual id key for Owner... because that doesn't mean anything to human users. I want the more human-friendly Owner.name value displayed on the screen instead.
The "list" and "show" Views explicitly deal with all attributes in the View's automatically-generated code, and I have the ability to tweak that code to control what's presented. However, the "create" and "edit" Views do not list out all the attributes. Instead those Views make some kind of Grails taglib call like this:
...
<fieldset class="form">
<g:render template="form"/>
</fieldset>
...
This call apparently auto-detects at runtime what the fields are, and makes its own decisions about how to display them. For domain objects having associations, it makes the bad decision of displaying the associated object's gibberish ID rather than a more human-friendly attribute.
Is there an "easy" (or at least "best practice") way for changing the way that fields are displayed on an "edit" or "create" view? Surely this is a common issue whenever using Scaffolding is used with domain objects having associations.
Oh, duh... you can just implement a "toString()" method on the associated domain object, having it return the field you want used for display purposes:
class Owner {
String id // not human-friendly
String name // human-friendly
// ...etc...
String toString() {
return name
}
}
Now when you're on a CRUD View for Contact, which has a field for its Owner association, what gets displayed on the screen is the Owner.name attribute rather than Owner.id or some ugly object reference.
I have a View class (OrderView.aspx) which shows the details of an order (Account Name, Order Date) as well as a list of order lines via the Repeater control. Each order line is represented by a User Control View (OrderLineView.ascx) which shows the details of the order line (Item Name, Quantity, Price). I have a model object called Order which I use as the data source for all of this, which I pass as the model object for the view.
Each OrderLineView user control has a Save and a Delete button. I have the Save button posting the contents of a form within the OrderLine control to a Save method on the Controller and then RedirectToAction back to the same Order page (this refreshes the whole page, nothing AJAXy about it). I have the Delete button linking to a method on the Controller that tries to delete, and then RedirectToAction back to the same Order page. If the delete fails, however, I want a little error message to show up next to the delete button when the page renders again(remember, there is a delete button for every order line on the page, so I only want the message next to the one I clicked). My questions:
1 - How do I pass this data from my Controller method to the specific User Control? Should I somehow add it in to the model? Seems like a bad idea (since it really isn't part of the model).
2 - Should I have a OrderLineController for the OrderLine operations as well as a OrderController for Order operations? I just want to know if best practice is to have a separate Controller for every view.
3 - I have seen how some people might call RedirectToAction with an anonymous type value like this:
RedirectToAction("ViewOrder", new { Id = 1234, Message = "blabla"});
but this makes the Message value show up in the URL string. I am OK with that, but would prefer that it doesn't show if possible.
4 - Also, for accessing properties of the Model from within the view, I find myself doing this all of the time:
foo(((someModelType) this.ViewData.Model).SomeProperty);
I don't like this for a number of reasons, one of which is the fact that I don't want my view to be coupled with the type of my model (which is why I am using ViewPage instead of ViewPage). I would much prefer to be able to have a call like this:
foo(ModelEval("SomeProperty"));
Is there such a thing? I have written my own, but would like it if I didn't have to.
1
Check out ModelState.
ViewData.ModelState.AddModelError("something.Name", "Please enter a valid Name");
ModelState is actually a dictionary, so you could identify the errors on a per-control basis. I don't know if this is a best practice, but it would probably work.
Try something along the lines of
ViewData.ModelState.AddModelError("something#3.Name", "Please enter a valid Name");
and in your view, you could put
<%= Html.ValidationMessage(string.format({"something{0}.Name", YourUniqueId))%>
4
You can strongly type your view, so you don't need that cast, but if you're concerned about tightly coupling, this may put you off. But having the strong type there is no more tightly coupled than having a magic string point to that property of the model anyway. The former just gives you type safety and the glory that is intellisense.
Since your OrderLine has a unique ID you can use that to construct a key to be placed in the ModelState errors container.
public ActionResult Delete(int? Id)
{
ModelState.AddModelError("OrderLine" + Id.Value, "Error deleting OrderLine# " + Id.Value);
...
}
and then use the ValidatinoMessage helper. This will check the ModelState to see if an error exists and if it does it will display the message. Otherwise it's blank.
<%= Html.ValidationMessage ("OrderLine" + Id)%>
In the next release of MVC Model will become a top level property so the following
foo(((someModelType) this.ViewData.Model).SomeProperty);
can be written as
foo(Model.SomeProperty);
Model objects should already be typed unless you're using public object as a property?