let parent = path[row-1]
let child = path[row]
let indexOfChild = matrix[parent.objectId!]!.index(of: child)
print("indexOfChild = \(indexOfChild)")
print("keyValuePair = \(matrix[parent.objectId!]!)")
print("child = \(child)")
let indexAfter = matrix[parent.objectId!]!.index(after: indexOfChild!)
As a result i'm getting this information printed in console.
As you can see "child" (which is the argument object with argumentText: "example") exists in the keyValuePair (they have the same objectId). Yet, it's index in keyValuePair appears nil in console. Apparently, the mere difference is: "child" has "0x608000333f60" next to it whereas the second argument object in keyValuePair has "0x600000321a40".
I don't know the purpose of these and how they get calculated but it seems to me index is found nil because these codes are different from each other
I have been trying to fix it for too long now. Could someone please help me through it?
indexOfChild = nil
keyValuePair = [<Argument: 0x608000334e60, objectId: IG9ekqMRw9, localId: (null)> {
ACL = "<PFACL: 0x60800042f200>";
argumentText = "the only thing is I can't get over how I feel when it ";
creatorId = hWRXoRvnYd;
level = 4;
parentId = j7GkpwUKsm;
reach = 0;
threadId = Dtq632QYJ2;
}, <Argument: 0x600000321a40, objectId: 56AsB1juNP, localId: (null)> {
ACL = "<PFACL: 0x600000235440>";
argumentText = "example ";
creatorId = hWRXoRvnYd;
level = 4;
parentId = j7GkpwUKsm;
reach = 0;
threadId = Dtq632QYJ2;
}]
child = <Argument: 0x608000333f60, objectId: 56AsB1juNP, localId: (null)> {
ACL = "<PFACL: 0x608000235540>";
argumentText = "example ";
creatorId = hWRXoRvnYd;
level = 4;
parentId = j7GkpwUKsm;
reach = 0;
threadId = Dtq632QYJ2;
}
fatal error: unexpectedly found nil while unwrapping an Optional value
The 0x608000333f60 and 0x600000321a40 values are memory address locations for the relevant variables. Since the address locations are different, I believe the two child instances are treated as two separate values and probably will not match. And that might be the issue you are running into.
It might be better to check the parent for the child instance by a unique ID value so that you can match the child instance in the parent array correctly. Does that make sense?
You can find the index for the child this way:
var index = -1
var found = false
for chld in matrix[parent.objectId!]! {
index = index + 1
if chld.objectId == child.objectId {
found = true
break
}
}
if found {
// The index value at this point is the index for the child
}
You could also simply filter the child array to find the child in the parent array which has the same objectId as your child variable and then find the index from the child array, something like this:
let chld = matrix[parent.objectId!]!.filter{ $0.objectId == child.objectId }.first
let indexOfChild = matrix[parent.objectId!]!.index(of: chld)
Related
I have built a survey using laanlabs/SwiftSurvey and I am able to get the results from the surveyComplete method as a dictionary.
The results return in a complex structure and I need to get the values for each response by the key tag of the questions array -> question object. This object contains an array of choices and within each choice object there is a key of selected. If the selected key's value is true (1) I need to get the text key's value that is in the same object. Some of these choices will have multiple selected keys with a value of true (1), if this is the case I'd like to concatenate the text key values with a comma in between the values.
The intention is then to insert the keys in to a SQLite database.
I am new to decoding dictionaries and traversing them in the correct way, I can access the dictionary print(dictionary) and also get into the the correct NSArray - print(dictionary["questions"] but from there I am stumped, could someone show me how please.
The results are below unfortunately its a large block apologies.
[
"version": 001,
"metadata":
{
"app_version" = "1.1";
build = 22;
debug = true;
},
"questions": <__NSArrayI 0x600000614d20>(
{
question = {
allowsMultipleSelection = 0;
choices = (
{
allowsCustomTextEntry = 0;
selected = 1;
text = Physician;
uuid = "224E1B76-D220-4068-AA22-6861E5F836CB";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = Dietitian;
uuid = "2DB2B6FB-E344-4BBF-A551-2FABE0DFF6AA";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = "Genetic Counsellor";
uuid = "A9BE7093-B95C-4BF4-B629-12FDA3154ABE";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = "Nurse/Nurse Practitioner/Physician Assistant";
uuid = "8E75A41B-0D8C-4ADA-A31C-2BC408F8269D";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = "Pharmacist / Pharmaceutical Industry";
uuid = "C943430D-EA48-4BCB-8ADF-011A223BDF36";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = "Academic/Researcher";
uuid = "E28377A4-37FC-4351-A857-88383A3D5A3B";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = "Patient/Patient Advocacy Group";
uuid = "E5836187-6C08-4272-A88E-40578F4FCF44";
},
{
allowsCustomTextEntry = 1;
selected = 0;
text = "Other (please specify)";
uuid = "EFF22342-48A9-4B8E-81A0-BB44D0E86EBC";
}
);
required = 1;
tag = "hcp-specialty";
title = "Please select the option that best describes your specialty:";
uuid = "7F77E248-8429-463E-9291-241B94BEE4F8";
};
type = 0;
},
{
question = {
autoAdvanceOnChoice = 1;
choices = (
{
allowsCustomTextEntry = 0;
selected = 1;
text = Yes;
uuid = "3C7A330D-F16B-4F3E-8ABC-6767A1A6332A";
},
{
allowsCustomTextEntry = 0;
selected = 0;
text = No;
uuid = "0E4F5360-FCCD-4860-9971-86E23BB8F6C1";
}
);
required = 1;
tag = "newborn-screening";
title = "Is newborn screening for classical homocystinuria available in your region/country?";
uuid = "F7C1A9D5-43AB-420D-80CF-F6644B95C73E";
};
type = 1;
},
{
question = {
feedback = "This is a free text response";
required = 1;
tag = "biggest-unmet-need";
title = "What do you believe is the biggest unmet need for patients living with classical HCU?";
uuid = "133E2EDC-8FF4-48D1-8BFA-3A20E5DA0052";
};
type = 4;
}
)
]
Based on their result example, you are getting JSON. Converting JSON to Dictionary is the easiest, of course, but also is the dirtiest. You are basically getting "whatever", so when it's time to use the data, you have to do a lot of - as you said - "decoding", validation, etc.
Instead of that, create a few Decodable structures that match your response. In this case you just need 3 structures:
struct Survey: Codable {
let questions: [Question]
}
struct Question: Codable {
let allowsMultipleSelection: Int?
let choices: [Choice]?
let required: Int
let tag: String
let title: String
let uuid: String
let feedback: String?
}
struct Choice: Codable {
let allowsCustomTextEntry: Int
let selected: Int
let text: String
let uuid: String
}
(I didn't verify every fields, you can adjust as needed. And you can omit any properties you don't need / don't care about.)
And then you decode it like this:
// Assume jsonData is your original JSON, which you currently decode as dictionary. So instead you do this:
let decoder = JSONDecoder()
let product = try decoder.decode(Survey.self, from: jsonData)
This approach allows you to
Most importantly, having a well-defined data makes working with database easier. You can even implement database encoder, based on your codable structures, which means you don't need to manually walk through columns of the database. Also when. you read from database, you get the same structures, no need to have 2 sets of rules / validations for database and dictionary you decoded.
This also allows you to be confident about data you decoded: it has proper names and types. You don't need to validate it (it was validated for you on decoding). You are in control which properties are required, which defaults to set, and so on. In more complicated cases, you may need to add manual decoding to your structures, but even then this manual decoding is inside the structure itself, easy to change / work with / test. All this instead of giant messy dictionary with "some stuff" in it.
I have two array, which has the same model.
I'm trying to find the object where it has the same id. I have tried this method which I can find it but how I can make it without for loop?
for item in userList {
let userSelection = user.list.first(where: {$0.id == item.id})
item.approved = userSelection.approved
print(userSelection)
}
Try something like this
let userSelection = user.list.filter({userList.map({$0.id}).contains({$0.id})})
Explanation:
//get all the ids from one list
let ids = userList.map({$0.id})
//filter the second list by including all the users whose id is in the first list
let userSelection = user.list.filter({ids.contains({$0.id})})
If you don't care about performance, you can use set.intersection:
let set1:Set<UserType> = Set(userList)
let set2:Set<UserType> = Set(user.list)
let commonItems = set1.intersection(set2)// Intersection of two sets
Even if your model is not Hashable, you can use sets to perform the validation:
if Set(userList.map{$0.id}).subtracting(user.list.map{$0.id}).count == 0
{
// all entries in userList exist in user.list
}
else
{
// at least one entry of userList is not in user.list
}
Here is my JSON response for a particular API.
Case 1
ChallengeConfiguration = {
AnswerAttemptsAllowed = 0;
ApplicantChallengeId = 872934636;
ApplicantId = 30320480;
CorrectAnswersNeeded = 0;
MultiChoiceQuestion = (
{
FullQuestionText = "From the following list, select one of your current or previous employers.";
QuestionId = 35666244;
SequenceNumber = 1;
},
{
FullQuestionText = "What color is/was your 2010 Pontiac Grand Prix?";
QuestionId = 35666246;
SequenceNumber = 2;
}
)
}
The key "MultiChoiceQuestion" returns an array with two questions. So here is my code.
let QuestionArray:NSArray = dict1.objectForKey("ChallengeConfiguration")?.objectForKey("MultiChoiceQuestion") as! NSArray
Case 2
ChallengeConfiguration =
{
AnswerAttemptsAllowed = 0;
ApplicantChallengeId = 872934636;
ApplicantId = 30320480;
CorrectAnswersNeeded = 0;
MultiChoiceQuestion = {
FullQuestionText = "From the following list, select one of your
current or previous employers.";
QuestionId = 35666244;
SequenceNumber = 1;
}
}
For Case 2 my code does not work and app crashes because it returns a dictionary for that specific Key. So how could I write a generic code that would work for all objects?
It looks like the key can contain either an array of dictionary values or a dictionary, so you just need to try casting to see which one you have.
so I would likely do it like this:
if let arr = dict1.objectForKey("ChallengeConfiguration")?.objectForKey("MultiChoiceQuestion") as? Array {
// parse multiple items as an array
} else if let arr = dict1.objectForKey("ChallengeConfiguration")?.objectForKey("MultiChoiceQuestion") as? [String:AnyObject] {
// parse single item from dictionary
}
You should never really use ! to force unwrap something unless you are completely certain that the value exists and is of the type you are expecting.
Use conditional logic here to test the response and parse it safely so that your app doesn't crash, even in failure.
I have NSArray() which is include names but there's duplicated names how can i remove them ?
After parse query adding the objects to the NSArray and its duplicated
var names = NSArray()
let query = PFQuery(className: "test")
query.whereKey("receivers", equalTo: PFUser.currentUser()!.username!)
query.findObjectsInBackgroundWithBlock {
(objects, error) -> Void in
if error == nil {
self.names = objects!
let set = NSSet(array: self.names as [AnyObject])
print(objects!.count)
// count is 4
// database looks like this (justin , kevin , kevin , joe)
If your names are strings you could create NSSet from array and it will have only different names.
let names = ["John", "Marry", "Bill", "John"]
println(names)
let set = NSSet(array: names)
println(set.allObjects)
prints:
"[John, Marry, Bill, John]"
"[Bill, John, Marry]"
Update #1
With new information in question (code fragment) it may look like this
var set = Set<String>()
for test in objects as [Test] {
set.insert(test.sender)
}
self.names = Array(set)
To expand on John's answer, an NSSet will, by definition, only contain a single copy of each object that hashes to be equal. So, a common pattern is to convert the array to a set and back.
This will work for any object type that has a reasonable implementation of -hash and -isEqual:. As John shows, String is one such object.
You could also do it with pure Swift:
let arrayWithDuplicates = [ "x", "y", "x", "x" ]
let arrayWithUniques = Array(Set(arrayWithDuplicates)) // => [ "y", "x" ]
But, it looks like you're already working with NSArray, so I think the John's example is more applicable.
Also, as my example shows, be aware that the order of the final array is not guaranteed to be in the same order as your original. If you want that, I think you can use NSOrderedSet instead of NSSet.
Here is a more complicated way to approach this that works. You could just run through a loop of the array and create a new one from the original. For example:
var check = 0
let originalArray:NSMutableArray = ["x", "y", "x", "z", "y", "z"]
let newArray: NSMutableArray = []
println(originalArray)
for var int = 0; int<originalArray.count; ++int{
let itemToBeAdded: AnyObject = originalArray.objectAtIndex(int)
for var int = 0; int<newArray.count; ++int{
if (newArray == ""){
break;
}
else if ((newArray.objectAtIndex(int) as! String) != itemToBeAdded as! String){
}
else if ((newArray.objectAtIndex(int) as! String) == itemToBeAdded as! String){
check = 1
break
}
}
if (check == 0){
newArray.addObject(itemToBeAdded)
}
}
Basically I set a check var = 0. for every object in the originalArray, it loops through the newArray to see if it already exists and if it does the check var gets set to 1 and the object does not get added twice.
Why is the realm-list containing the very same elements instead of different ones ?
As you can see in the picture below, there are two relam-objects (UndoMemoryNameEntry and NameEntry). The first one contains a list of 8 elements. The list's element-type is of type NameEntry !
My last NameEntry object is written with currentScorePlayer=1 and currentScoreMe=15 as you can see in the picture below:
The list in UndoMemoryNameEntry is correctly inserted the last NameEntry object. You find the insertion-code further down...
But now the problem: Why are all the existing list-elements as well changed to the newest inserted element ???? As you can see in the picture below, all the elements are unfortunately identical to the last one added - why ??????
If I change the NameEntry to the following :
And inserting at index=0 to the list, then the List changes to :
Why are all the elments changed ? And not just the inserted one ??? Thanks for any help on this !
My two realm-objects are :
class NameEntry: Object {
dynamic var playerName = ""
dynamic var isMyAdversary: Bool = false
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
}
and the List :
class UndoMemoryNameEntry: Object {
dynamic var undoPlayerName = ""
let NameEntryList = List<NameEntry>()
}
The following code creates the Realm-List :
// query rlm for existing object (with name adversary
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", adversaryName)
let undoPlayerName = rlm.objects(UndoMemoryNameEntry).sorted("undoPlayerName", ascending: true).filter(undoPredicate)
// if undoPlayerName object does not exist - then create it!
if (undoPlayerName.count < 1) {
rlm.beginWrite()
let undoEntry = UndoMemoryNameEntry()
undoEntry.undoPlayerName = adversaryName
rlm.add(undoEntry)
rlm.commitWrite()
}
The following code adds a "NameEntry"-Element in the List :
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", plaNameLab)
let undoPlayerName = rlm.objects(UndoMemoryNameEntry).sorted("undoPlayerName", ascending: true).filter(undoPredicate)
if (undoPlayerName.count == 1) {
rlm.beginWrite()
println(entry)
var undoEntry = undoPlayerName[0] as UndoMemoryNameEntry
undoEntry.NameEntryList.insert(entry, atIndex: 0)
rlm.commitWrite()
}
The above code-excerts work perfectly - except that the realm-List always changes all its elements to the one just inserted.
I finally found a solution:
First of all rearrange the two realm objects as follows:
class NameEntry: Object {
dynamic var playerName = ""
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
// the undo-list is better placed in the first object...
let undoEntryList = List<UndoMemoryNameEntry>()
override static func primaryKey() -> String? {
return "playerName"
}
}
class UndoMemoryNameEntry: Object {
dynamic var undoPlayerName = ""
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
// no primary key here since the undoEntry will have several items with the same undoPlayerName
}
Then when adding a "NameEntry"-Element in the List :
let predicate = NSPredicate(format: "playerName == %#", plaNameLab)
let playerName = rlm.objects(NameEntry).sorted("playerName", ascending: true).filter(predicate)
if (playerName.count == 1) {
rlm.beginWrite()
var entry = playerName[0] as NameEntry
// you need to create a new list object first !!!!!!!!!!!!
// ...in my initial example, this creation was missing !!!!!!
var siblingEntry = UndoMemoryNameEntry()
siblingEntry.undoPlayerName = plaNameLab
siblingEntry.currentScorePlayer = entry.currentScorePlayer
siblingEntry.currentScoreMe = entry.currentScoreMe
// insert new list-element
entry.undoEntryList.insert(siblingEntry, atIndex: 0)
// alternatively choose append if you want to add the element at the end of the list
entry.undoEntryList.append(siblingEntry)
// or choose the "ringbuffer-solution" given in the add-on below if you want to restrict the number of list-elements to ringbuffer-size !
// ...
rlm.commitWrite()
}
Add-on: If you want to create a ringbuffer having only a limited number of list-elements:
// create ringbuffer of 20 elements (20th element will be newest)
let ringBufferSize = 20
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", plaNameLab)
if (entry.undoEntryList.filter(undoPredicate).sorted("undoPlayerName").count < ringBufferSize) {
entry.undoEntryList.append(siblingEntry)
}
else {
// entry.undoEntryList.replace(ringBufferSize-1, object: siblingEntry)
entry.undoEntryList.removeAtIndex(ringBufferSize-1)
entry.undoEntryList.append(siblingEntry)
for index in 0..<ringBufferSize-1 {
let tempEntry1 = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[index] as UndoMemoryNameEntry
let tempEntry2 = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[index+1] as UndoMemoryNameEntry
tempEntry1.currentScorePlayer = tempEntry2.currentScorePlayer
tempEntry1.currentScoreMe = tempEntry2.currentScoreMe
}
let tempEntry = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[ringBufferSize-1] as UndoMemoryNameEntry
rlm.delete(tempEntry)
}