I am designing an application that will display dynamically-generated forms to the user who will then enter values into the form fields and submit those values for persistence. The form represents an employee evaluation.
One use case allows an administrator (from HR) to define the form fields. They should be able to create a new form, add/remove fields from a form and mark a form as 'deleted'.
The second use case is when a manager views the form and enters values into the form fields for a specific employee. They should be able to save the values at any time and recall the saved values when viewing the form again for the same employee.
Finally, when the manager is satisfied with the values they've entered for that employee, they can 'submit' the form data which persists the flattened data into the data warehouse for reporting purposes. When this is done, the 'working' copy of the data is removed so the form will display empty the next time they view it for that employee.
I am not concerned with the front-end at this point and working on the back-end service application that sits between the client and the data store. The application must provide a course-grained interface for all of the behavior required.
My question is how many aggregate roots do I actually have (and from that, how many repositories, etc)? Do I separate the form definition from the form data even though I need both when displaying the form to the user?
I see two main entities, 'EmployeeEvaluationSchema' and 'EmployeeEvaluation'. The 'EmployeeEvaluationSchema' entity would have a collection of 'FieldDefinition' value objects which would contain the properties that define a field, the most basic being the name of the field. The 'EmployeeEvaluation' entity would have a collection of 'FieldValue' value objects which contain the values for each field from the definition. In the simplest case, it would have a field name and value property. Next, the 'EmployeeEvaluation' could have a reference to 'EmployeeEvaluationSchema' to specify which definition the particular evaluation is based on. This can also be used to enforce the form definition in each evaluation. You would have two repositories - one for each entity. If you were to use an ORM such as NHibernate, then when you retrieve a 'EmployeeEvaluation' entity, the associated 'EmployeeEvaluationSchema' would also be retrieved even though there is a dedicated repository for it.
From your description it sounds like your objects don't have any behavior and are simple DTOs. If that is the case maybe you should not bother doing DDD. Can you imagine your entities without having getters? There are better ways to do CRUDish application than DDD. Again this is only valid if your "domain" does not have relevant behavior.
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I have a case in my customisation project, were I have a PXSelector that I want it to solely act as a lookup, and would not like the users to input any data via the selector and create new records.
I could not find a way to limit this from the attribute itself, therefore I tried to limit it from the events that the control fires. The idea was that in the FieldUpdating Event I would verify whether the value inserted by the user can be found in the selector's key column, if not I would revert it back to the old value. The problem was that cancelling the event had no effect on the selector and since I did not know what the previous value was, I could not revert it back manually.
It sounds like you are trying to use a filter. You need a PXFilter view which then could be used to display data in a grid for example.
You can search the source for "PXFilter to find good examples. One I found is APVendorBalanceEnq which uses public PXFilter<APHistoryFilter> Filter
PXFilter views are not committed to the database. Typically you would create a new DAC for the filter based on your needs but you can use existing DACs that are bound to tables without the fear of the data making it to the database. With the filter you simply use the field values rather than load records into the view.
In a JSF page I have to display the data from an entity.
This entity has some int fields which cannot be displayed directly but need to be translated into a descriptive string.
Between them some can have a limited number of values, others have lots of possible values (such as a wordlwide Country_ID) and deserve a table on the Db with the association (ID, description).
This latter case can easily be solved navigating via relationship from the original entity to the entity corresponding to the dictionary table (ID, description) but I don't want to introduce new entities just to solve translations form ID to description.
Besides another integer field has special needs: the hundred thousand number should be changed with a letter according to a rule such as 100015 -> A00015, 301023 -> C01023.
Initially I put the translation code inside the entity itself but I know the great limits and drawbacks of this solution.
Then I created a singletone (EntityTranslator) with all the methods to translate the different fields. For cases where the field values are a lot I put them inside a table which is loaded from the singletone and transformed in a TreeMap, otherwise the descriptions are in arrays inside the class.
In the ManagedBean I wrote a getter for EntityTranslator and inside the jsf I use quite long el statements like the following:
#{myManagedBean.entityTranslator.translateCountryID(myManagedBean.selectedEntity.countryID)}
I think the problem is quite general and I'm looking for a standard way to solve it but, as already stated, I don't want to create new 'stupid' entities only to associate an ID to a description, I think it is overkill.
Another possibility is the use of converters Object(Integer) <-> String but I'm more comfortable in having all the translation needs for an Entity inside the same class.
Your question boils down to the following simple line:
How can I display a field different from id of my entity in my view and how can I morph an integer field into something more meaningful.
The answer is that it depends on a situation.
If you solely want to input/output data, you don't need id at all apart from the possible view parameter like ?id=12345. In this case you can input/output anything you want in your view: the id is always there.
If you want to create a new entity most possibly you have a way of generating ids via JPA, or database, or elsehow besides the direct input from the user. In this situation you don't need to mess with ids as well.
If you want to use information on other entities like show user a dropdown box with e.g. a list of countries, you always have the option to separate label (let it be name) and value (let it be id), or even have a unique not null column containing the country name in your database table that will serve as a natural identifier. If you'd like to get data from the user using an input text field you always can create a converter that will do the job of transforming user input strings to actual entity objects.
Regarding the transformation of your integers, you've actually got several choices: the first one is to attach a converter for these fields that will roughly do 301023 -> C01023 and C01023 -> 301023 transformations, the second one is to write a custom EL function and the third one is to prepare the right model beforehand / do the transformations on-the-fly.
I'm trying to figure out the best way to handle a requirement I have for an Orchard module I'm building.
I have a ContentPart that has a few fields. One field is a ContentPicker that allows for multiple items to be associated to the part. The rest are descriptive information.
The issue I have is that I actually need to be able to include more than one of this ContentPart into a ContentType. I need to create a ContentType that has exactly 3 of this part.
Should I be making this into a field instead of a part? Is it even possible to have a ContentField that has other fields in it?
Or, should I somehow use all the same models and data structures, but somehow define it as 3 distinct parts?
Just wondering what the best practice to do something like this would be.
You can only have one part of each kind on a given type. You can't have fields that have other fields in it (instead - take an existing field and extend it with custom stuff).
As I understand, the actual problem is "how to make groups of fields with some metadata for each group", right? If so, there are a few approaches to solve the problem:
Create a custom field based on Content Picker (basically - take existing Content Picker and extend it with your metadata) and use this without the need for a separate part
Create one part to hold only the metadata for each field attached to it and attach 1 or more fields to it
Create 3 distinct parts. Parts should be thought of as extensions that add some unique features to an item. If you think it's logically ok to have 3 parts then go for it.
I have an odd issue.
I have client that wants a sharepoint list what is populated from a WCFService. That part is working quite well.
I have a bdcmodel that is mapping the WCF data and I can create an external list from the bdcmodel as well so that is working fine.
The issue I have is that one of the properties in the model is actually a collection of entities called Attributes. The objects in this collection simply have 2 properties Name and Value so really they are just a key value pair.
The client wants to see the list of attributes of the parent entity in the external list. So there would be an Attributes column and within that column would be the list of attributes for each parent object.
Is there even a way to do this? I am looking into Custom Field Types, but it seems like these are really intended to be singular values.
How would I create a list within and external list?
Any help anyone can give would be great even if its just to tell me that there really isn't a stable way to do this so I can go back to the client and tell them we will need to build a custom list to support this because the OOB external list and custom fields and custom field types won't support this kind of nested listing.
I decided to set up the custom field as a string and when I get my collection in from the BdcModel I am serializing it to JSON and then passing it to the field. When the field is viewed in display, edit or new I have overridden the FieldRenderingControl and I am tiling the collection out that way.
I have core data app with an entity OBSERVATION that has as one of its attributes DEALNAME.
I want to reference through Interface Builder or by making custom modifications to an NSArrayController a list of unique sorted dealnames so that I can use them in a pop-up.
I have attempted to use #distinctUnionOfSets (and #distinctUnionOfArrays) but am unable to locate the proper key sequence.
I can sort the ArrayController by providing a sort descriptor, but do not know how to eliminate duplicates.
Are the #distinct... keys the right methodology? It would seem to provide the easiest way to optimize the use of IB.
Is there a predicate form for removing duplicates?
Or do I need to use my custom controller to extract an NSSet of the specific dealnames, put them back in an array and sort it and reference the custom array from IB?
Any help would be appreciated. I am astounded that other have not tried to create a sorted-unique pop-up in tableviews.
You need to take a look at -[NSFetchRequest returnsDistinctResults]. That is the level you need to be handling the uniquing of data.
Although I do not have a definitive answer for you, I think there are two ways you can go about it.
The way you already started. You need to bind the contents array of the PopUp button, not just against the arrayController.arrangedObjects, but continue on the path and somehow filter only objects with distinct "DealName"s. This means - the arrayController presents ALL the entities (and may sort them for you) but the PopUp button will have its contents filter via some sophisticated binding to the array controller.
Make your filtering at the ArrayController level (as suggested in another answer here). Here it depends how you set up the array controller. If It is set up to use an "Entity" (vs. "Class") which means the array controller will fetch CoreData entities directly - you can modify its "Fetch" to only bring a subset of the "OBSERVATION" entities with distinct values of "DEALNAME". I don't know how to control WHICH entities are filtered out in this case. Otherwise, you can setup the arrayController to work with "Class" objects, and then you can fetch the entities yourself (in code) and populate the arrayController programmatically, with just the entities you like.
In the second option, the Popup button should be bound normally to the arrayController's arrangedObjects.