assuming the following example:
I have a User class and a Item class and a user can have many items
1) Is there a combined dynamic method to get all the items for a user and also sort them after a Property? I have a controller action that gets the items for a user and send them to the view, and the view will render them all with < g:each>. But I want to sort them by any property of Item without sorting the array after it is relived from GORM (using sort in controller or view).
So basically what I do now is items = Item.findAllByOwner(userInstance)
and then send the [items:items.sort{it.property}] to the view. I want to combine findAllBy with Item.listOrderByProperty()
2) Assuming that there is such a method as on 1) : I want to use it to escape the overhead of sorting the array after constructing it. Will such a method be more performant instead of making a sort{} on items ?
You can pass a map of options to findAllBy. Take a look at http://www.grails.org/doc/1.2.2/ref/Domain%20Classes/findAllBy.html .
Related
I have a tagging system in my application. Now there is one specific entity, for which I want to allow only one tag. Actually I want to assign a parent to a tag.
For this purpose I want to use a VaadinCombobox with lazy loading and filtering.
My data layer is Spring Boot Neo4J Data. There I have a repository like this:
Page<TagListDto> searchPaginated(String searchTerm, Pageable page);
This gives me a data transfer object used for list displays filtered by the searchTerm. The list is pageable. I use the same method for filtering Grids.
So I could do it like this, if I knew where to get the searchTerm from.
ComboBoxLazyDataView<TagListDto> dataView = parentTag.setItems(query ->
tagRepository.searchPaginated(searchTerm,
PageRequest.of(query.getPage(), query.getLimit())).stream());
parentTag.setItemLabelGenerator(TagListDto::getName);
But probably, I'll have to use a DataProvider and a FilterBuilder for the ComboBox, right?
So the answer is to use setItemsWithFilterConverter-method. What you enter into the combo-box field will be sent to the filter converter (2nd method parameter) as a String and then passed as property of the query object to execute the search (1st method parameter).
So if you need to convert the type of the search term from String to some other type, add wildcards or whatever, do it in the 2nd labda.
With query.getFilter() in the 1st lambda you can retrieve the search term and then use that to make the query to your backend.
Here's an example:
ComboBox<Person> personComboBox = new ComboBox<>();
personComboBox.setItemLabelGenerator(Person::getName);
personComboBox.setItemsWithFilterConverter(
query -> personService.searchPaginated(query.getFilter().orElse(""),
PageRequest.of(query.getPage(),
query.getLimit())).stream(),
personSearchTerm -> personSearchTerm
);
Question: Is it possible to build a class method scope that can query objects based on values inside an array in a table? If yes, how can I do this?
In my example, I have a “wells” table that has an array field called “well_tags”. I want to build a query that returns all objects that have a specified value (such as “ceramic”) in the wells_tags array. The basic query would be something like this:
#well = Well.all
#query = #well.where(“well_tags contains ceramic”)
And then the class method scope would look something like this, with the “well_tag_search” param passed in from the controller:
class Well < ActiveRecord::Base
def self.well_tag_filter(well_tag_search)
if well_tag_search.present?
where(“well_tags contains ceramic")
else
Well.all
end
end
I found another post that asks a similar question (see link below), but I cannot get the answer to work for me...the result is always 'nil' when I know there should be at least 1 object. I am a beginner using sqlite (for now) as my database and rails 4.0.
Active Record Query where value in array field
Thanks!
UPDATE: some progress
I figured out how to create an array of all the objects I want using the ‘select’ method. But I still need to return the results as an Active Record object so I create a class method scope.
#well = Well.select
{ |well| if well.well_tags.present?
then well.well_tags.include? ‘ceramic' end }
#well.class #=> array
Not sure where Show is coming from.
Can you try doing Well.all instead of Show.all?
I am trying to add records dynamically to an already populated UITable. In my UITableView class I have a custom List object
List<CustomObject> _data=new List<CustomObject>();
where I add records to from my webservice call like so:
_data.Add(Json(Object));// Json returns a list of CustomObject
//table is a UITableView
//this.table.InsertRows(_data);
I know this above line won't work because its expecting an NSIndexPath[] but I am not sure how to go about adding the new items an load only the new items added. I don't really follow objective C very well so examples I found don't help so much
Generally, you will add data to your List, and then call ReloadData() on your TableView. You usually only call InsertRows() if you want to insert data at a particular spot in the table based on some sort of user action.
You are trying to add a List of CusomObject as CusomObject to a List<CusomObject> ,that is not quite right.you should be adding a CusomObject to List<CusomObject>.
I am trying to send map from gsp to controller but the map is considered as a string in the controller
<g:remoteFunction
action="updateCart"
params="{startDate:stDt,endDate:endDt,cartId:pkid,shoppingCart:'${shoppingCart}'}"
update="resourcesSelectedId"/>
Here the shoppingCart is a grails map variable I am trying to send
Edit:
there was a typo in the code I posted above. Missed starting "{" in the params
params="{startDate:stDt,endDate:endDt,cartId:pkid,shoppingCart:'${shoppingCart}'}"
Updated my question as per my comments below
In my case shoppingCart is an object and it has, lets say for example, items and quantity of each item. I have some rules to be applied based on the items selected and quantity and determine the price for each item and show it back to the user. I want to do this processing the controller. Whenever user updates the cart I need to re-calculate and show it back to user. Is there any other better approach you would suggest to do this instead of passing the objects back and forth
Anytime you're using the params attribute, it has to be in the format of a Map anyway, which means including the [ ]. This also means you can exclude the ${ } from any values because grails will parse all these as potential variables.
<g:remoteFunction
action="updateCart"
params="[startDate:stDt,endDate:endDt,cartId:pkid,shoppingCart:shoppingCart]"
update="resourcesSelectedId"/>
However, keep in mind that you can't send objects. I'm not sure what shoppingCart is in your example, but it would only be able to be a simple value that can be represented as a String. Possibly you would want shoppingCart.id? Otherwise, that should get you going in the right direction.
I could able to overcome this issue by following below steps
converted the shoppingcart object to json string
Pass the json as part of the params
parse the json string server-side & process
pass the updated object back to gsp
When I use criteria queries, the result contains array list of lazy initialized objects. that is, the list has values with handler org.codehaus.groovy.grails.orm.hibernate.proxy.GroovyAwareJavassistLazyInitializer.
This prevent me from doing any array operation (minus, remove etc) in it. When I use, GORM methods, I get array list of actual object types. How can I get the actual objects in criteria query?
The code is listed below.
availableTypes = Type.withCriteria() {
'in'("roleFrom", from)
'in'("roleTo", to)
}
availableTypes (an array list) has one value , but not actual object but value with a handler of GroovyAwareJavassistLazyInitializer
availableTypes (an array list) has values with type Type
availableTypes = Type.findByRoleFrom(from)
---------- Update ----------
I did further troubleshooting, and this is what I found. Probably the above description might be misleading, but I kept it in case it helps.
When using findAllBy for the first time, I get proxy objects rather than the actual instance. Then, I invoke the method through an ajax call, the actual instance is loaded (anything to do with cache loading??). When I refresh the page, it again loads the proxy
def typeFrom = Type.findAllByParty(partyFrom)
there is another use of findAllBy in the same method, which always returns actual instances.
def relFrom = Relation.findAllByParty(partyFrom)
When compared the two classes, the attribute 'party' of class Roles is part of a 1-m relation. like
class Role {
RoleType roleType
LocalDate validFrom
LocalDate validTo
static belongsTo = [party : Party ]
...
}
I know if I do statement like Party.findAll(), the role instances would be proxy till they access. But, when using gorm directly on the class (Role), why I am getting the proxy objects ???
thanks for the help.
thanks.
Turns out are a couple of possible solutions which I came across but didn't try, such as
Overloading the equals method so that the proxy and the domain
object use a primary key instead of the hashCode for equality
Using a join query so that you get actual instances back and not proxies
GrailsHibernateUtil.unwrapProxy(o)
HibernateProxyHelper.getClassWithoutInitializingProxy(object)
One solution that worked for me was to specify lazy loading to be false in the domain object mapping.
History of this problem seems to be discussed here: GRAILS-4614
See also: eager load