Question

Using the (modified) examples in the Realm Swift documentation:

class Dog: Object {
  dynamic var name = ""
  dynamic var age = 0
  let puppies = List<Puppies>()
}
class Person: Object {
  dynamic var name = ""
  dynamic var picture: NSData? = nil // optionals supported
  let dogs = List<Dog>()
}

class Puppies: Object {
        dynamic var name = ""
}

Let's assume that the Person.name = Bob, and that Bob has several dogs added to his dogs List. I have added another model class called Puppies, which would represent puppies that belong to Bob's dogs. (Apparently Bob owns a kennel.)

How would I get the values to display the names of Bob's dogs and the number of puppies belonging to each dog in a UITableview?

More specifically, what is the code to extract the property values of the List of dogs that belong to Bob. I assume that once I get those values it won't be difficult to list them in the tableview cells.

I decide to use the slightly modified example from the documentation instead of my own code so that those who read this won't have to try and interpret my code, and be able to focus on the solution.

I have been able to save my data and believe I have made the relationships between the objects link properly, but don't know how to get the values of the List objects, based on the primary key I have in my top level model. The problem I have is that (using the example above): the puppies know what dog they belong to, and the dog knows the person it belongs to, but the inverse relationships don't seem to work.

(By the way; I used the LinkingObject examples in the documentation in a playground and it throws and error. I'm not sure if the examples are incomplete in some way.)

In the Realm Browser (displaying the Person object) I can see the data as entered but the link that shows [Dog] has a 0 next to it and when I click on the link, the table that shows is blank. Maybe solving that issues will be the answer to make everything else work.

Please excuse my ignorance. I'm still learning.

Answer 1

感谢Ahmad F.指出我正确的方向。

以下是答案：

我不知道如何在每个对象类中附加到list属性。按照上面的示例，它通过创建一个包含Person对象的变量来完成。然后realm.write函数看起来像这样。

newDog = Dog()
newDog.name = "Phydeaux"
.....
try! realm.write {
    currentPerson?.dogs.append(newDog)

How to get the values from Realm List to be used in a UITableview

1 个答案: