I have two table views
#IBOutlet var specialitiesAll: UITableView!
#IBOutlet var specialitiesAdded: UITableView!
and they each populate separate arrays
var allArray = Array<Dictionary<String, Any>>()
var addedArray = Array<Dictionary<String, Any>>()
One is populated with all items, the other is items the user added, both I get from an API
let newAddedArray = self.userProfile["specialities"] as! Array<Dictionary<String, Any>>
for item in newAddedArray
{
self.addedArray.append(["id" : item["id"]!, "text" : item["name"]!])
}
self.specialitiesAdded.reloadData()
getSpecialities(){ result in
for item in result
{
self.allArray.append(["id" : item["id"]!, "text" : item["text"]!])
}
self.specialitiesAll.reloadData()
}
My question is allArray has all the items, how would I either remove or skip the items that are in addedArray or newAddedArray?
You can first convert Array into Set and perform difference set processing. Hash table is very efficient and the order may be messy. Direct processing of Arrays is not efficient, but the order is guaranteed to be the same. According to the scene selection?
var employees: Set = ["Alicia", "Bethany", "Chris", "Diana", "Eric"]
let neighbors: Set = ["Bethany", "Eric", "Forlani", "Greta"]
employees.subtract(neighbors)
print(employees)
try this.
extension Array {
func containsObject(_ object: Any) -> Bool {
let anObject = object as AnyObject
for obj in self {
let anObj = obj as AnyObject
return anObj.isEqual(anObject)
}
return false
}
}
let array1: [[String: Any]] = [["a": 1, "b": "123"], ["c": 456.5]]
let array2: [[String: Any]] = [["a": 1, "b": "123"]]
let result = array1.filter{ !array2.containsObject($0) }
print(result)
//[["c": 456.5]]
I decided to go this route with no extensions
getSpecialities(){ result in
for item in result
{
if (self.addedArray.contains(where: { $0["id"] as! Int == item["id"] as! Int }) == false) {
self.allArray.append(["id" : item["id"]!, "text" : item["text"]!])
}
}
self.specialitiesAll.reloadData()
}
Related
I am trying to filter an array of structs that has array. Below are the data structures I am using. I want the inner array filtered also but it doesn't work
var objects = [SomeObject]() //array of objects
var filteredObject = [SomeObject]() //filtered array
var isSearching = false
struct SomeObject {
var sectionName: String
var sectionObjects : [History]
}
struct History {
var firstName: String
var lastName: Int
}
func searchBar(_ text: String) {
filteredObject = objects.filter({ (obj: SomeObject) -> Bool in
return obj.sectionObjects.filter { $0.firstName.contains(text.lowercased())}.isEmpty
})
print("====", filteredObject, "fill===")
}
let history = History(firstName: "John", lastName: 1)
let anotherHistroy = History(firstName: "Dee", lastName: 2)
let historyArray = [history, anotherHistroy]
let newObject = SomeObject(sectionName: "Section 1", sectionObjects: historyArray)
objects.append(newObject)
searchBar("Jo") // printing of filtered object should not have another history in it's sectionObjects
You might be looking for something like this:
func searchBar(_ text: String) {
filteredObject = []
for var ob in objects {
ob.sectionObjects = ob.sectionObjects.filter {
$0.firstName.contains(text)
}
if !ob.sectionObjects.isEmpty {
filteredObject.append(ob)
}
}
print("====", filteredObject, "fill===")
}
Could perhaps be done more elegantly with reduce(into:), but on the whole it is best to start simply by saying exactly what you mean. You can tweak as desired to take account of case sensitivity.
I have a core data framework to handle everything you can do with coredata to make it more cooperateable with codable protocol. Only thing i have left is to update the data. I store and fetch data by mirroring the models i send as a param in their functions. Hence i need the variable names in the models if i wish to only update 1 specific value in the model that i request.
public func updateObject(entityKey: Entities, primKey: String, newInformation: [String: Any]) {
let request = NSFetchRequest<NSFetchRequestResult>(entityName: entityKey.rawValue)
do {
request.predicate = NSPredicate.init(format: "\(entityKey.getPrimaryKey())==%#", primKey)
let fetchedResult = try delegate.context.fetch(request)
print(fetchedResult)
guard let results = fetchedResult as? [NSManagedObject],
results.count > 0 else {
return
}
let key = newInformation.keys.first!
results[0].setValue(newInformation[key],
forKey: key)
try delegate.context.save()
} catch let error {
print(error.localizedDescription)
}
}
As you can see the newInformation param contains the key and new value for the value that should be updated. However, i dont want to pass ("first": "newValue") i want to pass spots.first : "newValue"
So if i have a struct like this:
struct spots {
let first: String
let second: Int
}
How do i only get 1 name from this?
i've tried:
extension Int {
var name: String {
return String.init(describing: self)
let mirror = Mirror.init(reflecting: self)
return mirror.children.first!.label!
}
}
I wan to be able to say something similar to:
spots.first.name
But can't figure out how
Not sure that I understood question, but...what about this?
class Spots: NSObject {
#objc dynamic var first: String = ""
#objc dynamic var second: Int = 0
}
let object = Spots()
let dictionary: [String: Any] = [
#keyPath(Spots.first): "qwerty",
#keyPath(Spots.second): 123,
]
dictionary.forEach { key, value in
object.setValue(value, forKeyPath: key)
}
print(object.first)
print(object.second)
or you can try swift keypath:
struct Spots {
var first: String = ""
var second: Int = 0
}
var spots = Spots()
let second = \Spots.second
let first = \Spots.first
spots[keyPath: first] = "qwerty"
spots[keyPath: second] = 123
print(spots)
however there will be complex (or impossible) problem to solve if you will use dictionary:
let dictionary: [AnyKeyPath: Any] = [
first: "qwerty",
second: 123
]
you will need to cast AnyKeyPath back to WritableKeyPath<Root, Value> and this seems pretty complex (if possible at all).
for path in dictionary.keys {
print(type(of: path).rootType)
print(type(of: path).valueType)
if let writableKeyPath = path as? WritableKeyPath<Root, Value>, let value = value as? Value { //no idea how to cast this for all cases
spots[keyPath: writableKeyPath] = value
}
}
I want to iterate through this array and separate out the names that have status true.
var array = [["name":"joe", "status":false ],["name":"will", "status":false],["name":"smith" , "status":false]]
This should do the trick.
var array = [["name":"joe", "status":true ],["name":"will", "status":true],["name":"smith" , "status":false]]
let filteredDictionary = array.filter( { $0["status"] as? Bool ?? false } )
var names = [String]()
for dictionary in filteredDictionary {
if let nameFound = dictionary["name"] as? String {
names.append(nameFound)
}
}
I recommend that you use a struct to store the values instead of a dictionary. Something like this.
struct Person {
var name: String
var status: Bool
}
If you have it like this in a Person array, it becomes less complicated as dictionary value optional handling can be avoided.
var personArray = [Person(name: "joe", status: true), Person(name: "will", status: false)
let names = personArray.filter( {$0.status} ).map( {$0.name} )
You can use a simple filter is you want to keep both the status and name, otherwise use compactMap is you just want to keep the name.
let statuses = [["name":"joe", "status":true ],["name":"will", "status":false],["name":"smith" , "status":false]]
let trueStatuses = statuses.filter({$0["status"] as? Bool == true}) // [["name": "joe", "status": true]]
let namesWithTrueStatus = statuses.compactMap{$0["status"] as? Bool == true ? $0["name"] as? String : nil} //["joe"]
I'm new to Swift programming. For my particular project, I'm trying to filter a dictionary with some user input, and the dictionary's value consists of an array.
Here is some sample code, and what I'm trying to accomplish:
var dictionary = ["a": ["aberration", "abc"], "b" : ["babel", "bereft"]]
var filteredDictionary = [String: [String]]()
var searchText = "aberration"
//getting the first letter of string
var firstLetter = searchText[searchText.startIndex]
With this particular searchText, I'm trying to get:
filteredDictionary = ["a": ["aberration"]]
Edit: I want the dictionary to return with the first letter as its key, and the values with what searchText matches up with. Sorry if it I wasn't clear.
Here is some code I have tried, but obviously, I can't get it to work:
filteredDictionary = dictionary.filter{$0.key == firstLetter && for element in $0.value { element.hasPrefix(searchText) }}
Any help would be appreciated. Thanks.
Here's a solution that maps the values based on the search and then filters out the empty results.
var dictionary = ["a": ["aberration", "abc"], "b" : ["babel", "bereft"]]
var searchText = "aberration"
let filteredDictionary = dictionary.mapValues { $0.filter { $0.hasPrefix(searchText) } }.filter { !$0.value.isEmpty }
print(filteredDictionary)
Output:
["a": ["aberration"]]
Try this:
var dictionary = ["a": ["aberration", "abc"], "b" : ["babel", "bereft"]]
var searchText = "aberration"
var filteredDictionary = dictionary.filter { (key, value) -> Bool in
return (value as! [String]).contains(searchText)
}.mapValues { (values) -> [String] in
return [searchText]
}
print(filteredDictionary)
You can use a combination of filter and map to achieve the desired result.
Output:
["a": ["aberration"]]
let firstLetter = String(searchText[searchText.startIndex])
let filteredDictionary = dictionary
.reduce(into: [String: [String]]()) { (result, object) in
if object.key == firstLetter {
let array = object.value.filter({ $0.hasPrefix(searchText) })
if array.count > 0 {
result[object.key] = array
}
}
}
Output:
["a": ["aberration"]]
I've already check all of those topics:
How to save an array of custom struct to NSUserDefault with swift?
How to save struct to NSUserDefaults in Swift 2.0
STRUCT Array To UserDefaults
I have a struct containing some Strings and an other struct: MySection.
struct MySection {
var name: String = ""
var values: [MyRow] = []
}
And there is MyRow which is store in MySection.values
struct MyRow {
var value: String = ""
var quantity: String = ""
var quantityType: String = ""
var done: String = ""
}
Two arrays for use it
var arraySection: [MySection] = []
var arrayRow: [MyRow] = []
And in my application, I add dynamically some values in those arrays.
There is the delegate method for get datas from my second ViewController
func returnInfos(newItem: [MyRow], sectionPick: String) {
arrayRow.append(MyRow())
arrayRow[arrayRow.count - 1] = newItem[0]
manageSection(item: sectionPick)
listTableView.reloadData()
}
And there is the manageSection function.
func manageSection(item: String) {
var i = 0
for _ in arraySection {
if arraySection[i].name == item {
arraySection.insert(MySection(), at: i + 1)
arraySection[i + 1].values = [arrayRow[arrayRow.count - 1]]
return
}
i += 1
}
arraySection.append(MySection())
arraySection[arraySection.count - 1].name = item
arraySection[arraySection.count - 1].values = [arrayRow[arrayRow.count - 1]]
}
My need is to store datas of the two arrays in UserDefaults (or CoreData maybe??) and use these datas when the user going back to the application.
I don't know how to do it, I've already try methods from the 3 topics but I'm not even doing a good job.
How can I do it?
Thanks guys!
Since both types contain only property list compliant types a suitable solution is to add code to convert each type to a property list compliant object and vice versa.
struct MySection {
var name: String
var values = [MyRow]()
init(name : String, values : [MyRow] = []) {
self.name = name
self.values = values
}
init(propertyList: [String: Any]) {
self.name = propertyList["name"] as! String
self.values = (propertyList["values"] as! [[String:String]]).map{ MyRow(propertyList: $0) }
}
var propertyListRepresentation : [String: Any] {
return ["name" : name, "values" : values.map { $0.propertyListRepresentation }]
}
}
struct MyRow {
var value: String
var quantity: String
var quantityType: String
var done: String
init(value : String, quantity: String, quantityType: String, done: String) {
self.value = value
self.quantity = quantity
self.quantityType = quantityType
self.done = done
}
init(propertyList: [String:String]) {
self.value = propertyList["value"]!
self.quantity = propertyList["quantity"]!
self.quantityType = propertyList["quantityType"]!
self.done = propertyList["done"]!
}
var propertyListRepresentation : [String: Any] {
return ["value" : value, "quantity" : quantity, "quantityType" : quantityType, "done" : done ]
}
}
After creating a few objects
let row1 = MyRow(value: "Foo", quantity: "10", quantityType: "Foo", done: "Yes")
let row2 = MyRow(value: "Bar", quantity: "10", quantityType: "Bar", done: "No")
let section = MySection(name: "Baz", values: [row1, row2])
call propertyListRepresentation to get a dictionary ([String:Any]) which can be saved to User Defaults.
let propertyList = section.propertyListRepresentation
Recreation of the section is quite easy, too
let newSection = MySection(propertyList: propertyList)
Edit
Use the propertyList initializer only if you get data from UserDefaults in all other cases use the other initializer.
For example replace
#IBAction func addButtonPressed(_ sender: Any) {
newProducts.append(MyRow(propertyList: ["":""]))
newProducts[newProducts.count - 1].value = nameTextField.text!
newProducts[newProducts.count - 1].quantity = quantityTextField.text!
newProducts[newProducts.count - 1].quantityType = type
newProducts[newProducts.count - 1].done = "No"
delegate?.returnInfos(newItem: newProducts, sectionPick: typePick)
navigationController?.popViewController(animated: true)
}
with
#IBAction func addButtonPressed(_ sender: Any) {
let row = MyRow(value: nameTextField.text!,
quantity: quantityTextField.text!,
quantityType: type,
done: "No")
newProducts.append(row)
delegate?.returnInfos(newItem: newProducts, sectionPick: typePick)
navigationController?.popViewController(animated: true)
}
and replace
func returnInfos(newItem: [MyRow], sectionPick: String) {
arrayRow.append(MyRow(propertyList: ["":""]))
arrayRow[arrayRow.count - 1] = newItem[0]
manageSection(item: sectionPick)
listTableView.reloadData()
}
with
func returnInfos(newItem: [MyRow], sectionPick: String) {
arrayRow.append(newItem[0])
manageSection(item: sectionPick)
listTableView.reloadData()
}
Basically first create the object, then append it to the array. The other way round is very cumbersome.