Why Can't I Get The Index of a Filtered Realm List

Why can't I get the index of a filtered realm List?

I figured out the solution. The filter syntax I used .filter({ $0.title == "Child" }) isn't the Realm filter, and converts the List to a LazyFilterCollection<List<Model>>, which doesn't seem to be compatible with searching for the index of a realm object.

The fix was to use the format .filter("title == %@", "Child"), which returns a realm Results object.

Filtering results from Realm

You can do this way:

Realm is not setup in my project so i am doing with struct.

Struct of Location:

struct Locations {

    let latitude: Double
    let longitude: Double
}

    // Your Realm result Array
    var theLocations = [Locations]()

    // Adding Dummy Data into theLocations Array
    theLocations.append(Locations(latitude: 37.33454847, longitude: -122.03611286))
    theLocations.append(Locations(latitude: 37.33454218, longitude: -122.03638578))

    // latitude and longitude to store values
    var arrLat = [Double]()
    var arrLong = [Double]()

    // Looping  through theLocations Array and Seperate latitude and longitude to append to array
    theLocations.forEach{ location in
        arrLat.append(location.latitude)
        arrLong.append(location.longitude)
    }

Hope this will help you.

Update the list when data is filtered from the realm database in android

Ok so finally found a solution to the about question after expermenting various things. All you need to do is call updateData() method of the RealmRecyclerViewAdapter which you will extend to your normal recyclerview.

Below code snippet provide the solution.

realm.executeTransaction(new Realm.Transaction() {
                @Override
                public void execute(@NonNull Realm realm) {
                    userModels = realm.where(UserModel.class).greaterThanOrEqualTo("age", 20).findAll();
                }
            });
            dataListAdapter.updateData(userModels);

The main point to keep in mind in above code is that you have to notify data outside the transaction block. If not done outside block, app will crash stating you cannot notify data when transaction is running.

Hope it helps someone somewhere.

Happy coding!!!

How to filter a realm subclass swift

There are actually multiple questions here. First we need to change the use of of the word subclass to instance. There are no subclasses in the question.

Note that Realm is conceptually an `Object' database so we're going to use the word 'object' to refer the objects stored in Realm (the 'instances' when they've been loaded in to memory)

I will rephrase each for clarity:

1. How do I return all SubscriptionClass objects?

let results = realm.objects(SubscriptionClass.self)

2. How do I return one specific SubscriptionClass object if I know the
   primary key?

let oneObject = realm.object(ofType: SubscriptionClass.self, forPrimaryKey: theObjectsPrimaryKey)

3. How do I return all of the SubscriptionClass objects that match a
   specific criteria; where the question property equals What is 5*5

let results = realm.objects(SubscriptionClass.self).filter("question == 'What is 5*5'")

and I will slide in #4: this queries for all questions as in #3 but only returns the very first one it finds. This can be dangerous because Realm objects are unordered so if there are ever more than one object, it could return a different first object each time it's used

if let oneObject = realm.objects(SubscriptionClass.self).filter("question == 'What is 5*5'").first {
    //do something with the object
}

Subclass:

A subclass inherits the superclass's functionality and extends it to provide additional functionality. Here's a subclass that adds a difficulty property to a subclass of SubscriptionClass (the 'super class')

class SubscriptionWithDifficultySubClass: SubscriptionClass {
   var difficulty = ""  //Easy, Medium, Hard etc
}

and then a different subclass that provides a subject property:

class SubscriptionWithSubjectSubClass: SubcriptionClass {
  var subject = ""  //Math, Grammar, Science etc
}

Realm Swift - How to remove an item at a specific index position?

Results are auto-updating and you cannot directly modify them. You need to update/add/delete objects in your Realm to effect the state of your Results instance.

So you can simply grab the element you need from your Results instance, delete it from Realm and it will be removed from the Results as well.

Assuming the Results instance shown in your question is stored in a variable called recipes, you can do something like the following:

let recipeToDelete = recipes.filter("id == %@","04b8d81b9e614f1ebb6de41cb0e64432")
try! realm.write {
    realm.delete(recipeToDelete)
}

Filter an object on a nested array in Realm Swift

If I understand correctly, I think a query like this will do what you're after:

func getFriendChatConversationModel(_ friendID: String) -> ChatConversationModel? {
    let realm = try! Realm()
    let chatConversationModels = realm.objects(ChatConversationModel.self).filter("typeIndex = %@", ChatTypes.ChatType.oneToOne.index)
    return chatConversationModels.filter("ANY userAcitivities.userID == %@", friendID).first
}

How to filter object from Realm database in Swift

You are using the wrong operator in a realm, please check my answer below.

for item in realm.objects(data.self).filter("id == 2 AND user_id == 4") {
   print(item)
}

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