I'm using database first with EF 6 and when I add a SQL view it doesn't generate any navigation properties.
Currently we use a hack where we have a table with the same columns and relations as the view which we rename to the view's name when we want to regenerate the EF entities, however this is obviously far from ideal.
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I'm creating an MVC5 web application and was curious if what I'm doing is considered bad practice or not.
I've already made a table with paging. This is created by a partial view that loops through the models id, code and name properties and displays them. Since I want to make a generic table I've decided to derive all models from a model base class (BusinessObjectModel) and give that to the partial view. I've modified the partial view to use reflection to get the values of every property this way the table can display every property of the model. This works great and the only thing left to do is to create a custom attribute tag to control which property is displayed in the list.
Is putting such logic into the view considered as bad practice? Should I create a helper that would assemble this view in the controller instead?
I have an MVC app using EF. The models, views and controllers are fine and working well.
I have to change my View Models, so the Views are now based on these changed models.
I don't want to manually change all 50 views one by one. I'm asking if there is a way to re/generate the existing Views automatically, based on the changed models declared in the View without deleting them and creating them again.
Thanks in advance.
In my iOS app, there are various Core Data entities that represent things like Appointments, Notes and Contacts.
I'd like the user to be able to edit selected attributes of each entity via a UITableView. Similar to the iOS Calendar app, when you click 'Edit', you're presented with a UITableView with editable values for Start Time, End Time, etc.
It's occurred to me that there could be a large amount of code re-use going on here, so I'm now considering creating a generic class, ManagedObjectEditorViewController that takes a managed object, displays selected attribute values within a table view, formatted according to their type, and allows them to be edited.
I can think of several neat ways of doing this, but before I spend a long time on this, I'm wondering if there's already something out there to accomplish this task? It seems like such a frequently used approach that I can't believe there isn't already some open source code out there.
Anyone heard of, or used anything similar?
I am about to do the same thing. Just started and works so far. A table that represents an NSManagedObject (Detail to a master view controller, has aspects of a master view controller itself.).
The whole table represents one NSManagedOjbect. There are fields and other controls that correspond with the simple properties.
There are to-one references where the referenced object is just displayed but can be changed.
There are to-one references which are editable NSObjects itself where 1 and exactly 1 of them exists.
There are to-many references which can be added, deleted and edited. Pretty similar to the calendar app or the address book app. (from a functional point of view. It looks different though).
For that I establish a delegate between the table cells and the view controller. This is mainly because I try to stick on the MVC pattern.
E.G. the cell serves as delegate for UITextViews, UITextFields or as target for Buttons etc.
The (Detail-) View controller which owns the NSManagedObject and all related objects serves as my delegate for the cells. It provides methods similar to IBActions to the cells so that the cell can 1) inform about the event and 2) hand over a related view, if required (I need that to display some popups accordingly) and 3) the object itself e.g. the object that is to be deleted or a person-object for which the data is to be fetched from the address book etc.
The View controller can then does its very own duties which is invoking other view controllers (Send Mail, select from Address Book, present a popover with options for the user to choose from, ...).
I just built that up yesterday evening. (It is a free-time project of mine).
I am happy so far but the concept is not really proven yet :) .
What is your current favorite approach?
I created an iOS app that allowed me to enter data into database and then display in tableview (using NSFetchedResultsController & tableView cellForRowAtIndexPath). This worked. Now, I added 3 one-to-many relationships and another entity and I need to load up the entity (on the one side of the one-to-many) from the db instead of pulling it directly from the db so that the data can be used in the relationships. Do I still use NSFetchedResultsController?
relationshipEntity2 is the one-to-many relationship between Entity1 & Entity2. The many point to Entity2
I know I'm supposed to use:
Entity2 *entity2 = [[self.entity1.relationshipEntity2 allObjects]
objectAtIndex:indexPath.row];
I am new to iOS development and even newer to Core Data but I must learn it. Any bit of help or pointing to a book or tutorial I haven't come across yet would be greatly appreciated. I haven't had much luck finding anything that does what I'm supposed to be doing.
Thanks and have a great week!
-------added for more description on project-------
I'm given the task of having a View Controller with a 3-part segmented button. There is also an add UIButton that pops up a view (bringing subview to the front, not a popover segue) with a UITextField for input to add to the table view on the view controller. There are 2 entities and three 1-to-many relationships. There is 1 relationship for each button on the segmented button. If the user, has the first part of the segmented button selected, adding a value to the popup textbox, should only add it to the table view seen when the first segmented button is selected. I have the CoreDataGeneratedAccessors created. I had this project saving data to database and fetching data to present in the table view but that was before the segmented part was added. Now I have to figure out out to separate the data into "collections" and then show all of say the first collection when the first segment of the segmented button is chosen. I'm just learning and just figured it out without the segmented part and now it's changed on me. I've worked with relational databases but in iOS it seems like it's new again.
Your question is by no means clear. You are not describing any problem, nor do you explain intelligibly what you want to accomplish.
Trying to infer your meaning: yes, you would continue to use your fetchedResultsController. This controller gives you the right object for each indexPath. When building your cell contents, you can easily get to the relationship entities with entity.relationship.
The code above will not work because entity.relationship returns an NSSet which is an unordered group of objects. (The additional allObjects does nothing and is redundant.) Therefore, objectAtIndex will not work (this only works for NSArray objects).
Hope this helps.
I have an entity which has a navigation property. I would like to define derived entities from the base entity using a field in the navigation property as the discriminator. Is this possible. I could not find a way to do this in the designer.
No it is not possible with navigation property. It should be possible to map two tables in 1:1 relation into single entity. You can try to combine it with table per hiearchy mapping. I'm interested if it works but i don't have chance to try it now.