I am new to iOS development (and objective-C & Xcode 4.3) and I want to create an app with profiles for users. I understand how to use Core Data to make a table with entities and that's all fine, but I don't know how I would go about creating a model so that a user can save a list of items (ie a MutableArray).
For example I need to have a username (for the profile) and than a list of strings that are saved to his account.
Would I need to just create an table with username and string item and than just query for all tuples that contain the username. Is there a simple way to serialize an object and save it the same way it's done in java.
Thank You.
You need to create a one-to-many relationship (which makes a NSSet of "destination" objects, or if you want to keep them in the specified order, click Ordered and it will be a NSOrderedSet).
Once you have the relationship, you can add multiple items to it and access it via the set.
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I have an array that is saved on the policyPeriod level right now called listOfAdditionalInsured. This list is display on one of the pages in the UI in PC.
The issue that I am having is that each time there is a policy change it will erase the data on that list because it's on the policyPeriod level. I see other arrays in PolicyPeriod that are not deleted during policy change and will appear fine. They look like they are effdated entities.
I am new to this so I am trying to figure out how to keep an array on the policyPeriod level but let it be editable during a change. I have tried putting it on the Policy level but it will change the array for all the transactions if I do it that way. I want each transaction to be able to edit the list in its own way.
Make sure your array entity is an Effective Dated entity and that the effDatedBrachType is PolicyPeriod. Take a look at how PolicyContactRole is implemented and try to do the same.
I have some points on a map with associated informations contained by Core Data, to link the points on the map with the associated info, I would like to have an ID for each point, so in my entity, I would need some ID property, I have read that Core Data has it's own IDs for every managed object but I'm wondering wether or not it would be a good approach for me to directly use them or if I should create my own ID system ?
If you think I should create my OWN ID system, how would I do that ?
Thank you.
CoreData is not an relational database and you should avoid thinking about own ID’s. You may need them only for syncing purposes with external databases. For more precise answer, you should write how your model looks.
[edited after comment]
I don't see that you need any relations. Let's sat you have MapPoint entity with lat, and long properties. If there is only one user note, you just add another property to it like notes. If you have many informations (many records) stored with one MapPoint you need to add Notes entity with properties note and mappoint and make a relation between them. When you insert new Notes object into CoreData you set mappoint property to already existing MapPoint object (fetched after user tap).
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 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.
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.