I got User Defaults with the key "abc" for example and it contains a string.
The last string stored in this key is "aaa".
Now, I want to store an additional value for this key, but I don't want to delete the last value "aaa" because I need it.
I want to have an Array of strings contains at the second retreive: ["aaa","some_other_value", "some_other_value2"...].
This is my code so far to store the information in user defaults:
self.user_defaults.set(self.myTextField.text, forKey:"asd")
This is the code for get the data:
if let arr = user_defaults.string(forKey:"asd"){
print (arr)
}
Try follwing code for save new value :
if let arr = user_defaults.array(forKey: "asd")
{
var arrvalues = arr as! [String]
arrvalues.append(self.myTextField.text)
self.user_defaults.set(arrvalues, forKey:"asd")
self.user_defaults.synchronize()
print (arr)
}
else
{
self.user_defaults.set([self.myTextField.text], forKey:"asd")
}
This is the code for get the data:
if let arr = user_defaults.array(forKey:"asd"){
print (arr)
}
let asdArr = [String]()
if NSUserDefaults.standardUserDefaults().objectForKey("asd") != nil {
asdArr = NSUserDefaults.standardUserDefaults().objectForKey("asd")
}
asdArr.append(self.myTextField.text)
NSUserDefaults.standardUserDefaults().setObject(asdArr, forKey: "asd")
Related
I am trying to filter my dictionary according to user input in UISearchController. I have following model and array of objects.
struct People {
var name: String
var id: Int
}
let first = People(name: "Atalay", id: 1)
let second = People(name: "Ahmet", id: 2)
let third = People(name: "Mehmet", id: 3)
let fourth = People(name: "Yusuf", id: 4)
let peoples: [People] = [first, second, third, fourth, fifth]
I put them into a dictionary to create section indexed table view with following code.
var dict: [String: [People]] = Dictionary(grouping: peoples, by: { (people) -> String in
return String(people.name.prefix(1))
})
Above code gives me a dictionary with first letter of People names. Now, I would like to filter my array according to user input. However, I tried following code for filtering but it is not working as I expected.
let filteredDict = (dict.filter { $0.1.contains { $0.name.lowercased().contains("ata") } })
It returns all "A" letter section indexes like ["A": People(name: "Atalay", id: 1), People(name: "Ahmet", id: 2)]
How can I achieve filter also my array inside dictionary?
If I'm not mistaken, you want your final dictionary to have all the keys and only the filtered array of items as the values. If that is right, reduce is the tool for that:
let filtered = dict.reduce(into: [String: [People]]()) {
$0[$1.key] = $1.value.filter { $0.name.lowercased().contains("ata") }
}
I decided it was simplest to get this right by using an old fashioned for loop and filter each group separately
var filtered = [String: [People]]()
for (k, v) in dict {
let result = v.filter {$0.name.lowercased().contains("ata")}
if result.count > 0 {
filtered[k] = result
}
}
Note that if you want to keep all the groups in the result dictionary just skip the if result.count > 0 condition
How can I achieve filter also my array inside dictionary?
You should have an array first, you can use flatMap to group all the values in your filteredDict
let array = filteredDict.flatMap { $0.value }
Then you just filter the array as usually
let filteredArray = array.filter { $0.name.lowercased().contains("ata") }
I have Array which contain ID like
var ID = ["782", "783", "784", "785", "786", "788", "789", "790", "791", "792", "793", "795", "805"]
And One Arr Of Dictionary like
Var arr2 = [["ID":"782","AmenitiesURL":"xyx.com"],["ID":"783","AmenitiesURL":"xybx.com"],["ID":"784","AmenitiesURL":"xyax.com"]]
Aslo see in image. Now I want to get the url of the ID.
Ex. if arr ID= 784 Then i want find that ID in the arr2 and get their url and append in New array,
In short Two array one is for ID and other for URL.
To get the URL of a specific id
let id = "784"
if let dict = arr2.first(where: { $0["ID", default:""] == id }), let urlString = dict["AmenitiesURL"] {
print(urlString)
}
You can get that working using the following approach:
let urls = ID.compactMap { (id) in
return arr2.first(where: {$0["ID"] == id})?["AmenitiesURL"]
}
Output:
print(urls) //["xyx.com", "xybx.com", "xyax.com"]
For all the ids in ID array, you'll get AmenitiesURL values from arr2 array.
Another approach. Though this one retains the structure of arr2
let filteredArray = arr2.filter { dict -> Bool in
for id in ID{
if dict["ID"] == id{
return true
}
}
return false
}
I just want to create a dictionary with the help of for loop
sample code :
var counter: Int = 1;
var pageCountDict = [String:Any]();
for filterCount in counter..<6
{
if let count = "page_\(filterCount)_vtime" as? String
{
pageCountDict = [count: timeInterval_Int];
}
}
print(pageCountDict);
This print command give me only last value of forloop
I just want all the value of this variable pageCountDict in a dictonary
The way to assign to a dictionary is first use the subscript and assign the value to it:
pageCountDict[YourKey] = YourValue
Also, you can see many examples and explanations in Apple documentation regarding dictionaries.
With each loop, you are replacing the dictionary with one that contains only one element. What you want to do is this :
pageCountDict[count] = timeInterval_Int
Also, you shouldn't need the as? String part. This should be sufficient :
for filterCount in counter..<6
{
pageCountDict[count] = "page_\(filterCount)_vtime"
}
var pageCountDict = [String:Any]()
You can add values to this dictionary by merging previous contents and new data as follows...
let counter: Int = 1
var pageCountDict = [String:Any]()
for filterCount in counter..<6
{
let value = 9
let count = "page_\(filterCount)_vtime" //'if' is not needed as it is always true
pageCountDict.merge([count: timeInterval_Int], uniquingKeysWith:{ (key, value) -> Any in
//assign value for similar key
timeInterval_Int
})
}
print(pageCountDict)`
might sound like a basic question--but I'm not seeing where I am going wrong..
I end up with either of these two scenarios:
I keep getting the error "Could not cast value of type __NSCFNumber to NSSTring". if I use extractedSku = skuList[i]!.value["sku"] as! String
If I remove as! String it saves it, but it isn't saved as a string. How do I get this to be saved as a string?
I have appended data from firebase into an array
skuArray = [AnyObject?]()
in viewDidLoad, I am iterating skuArray to extract the 'sku' and store into a variable.
var skuArray = [AnyObject?]()
var productDetailArray = [AnyObject?]()
data stored in Sku Array is:
[Optional(Snap (aRandomKey) {
active = 1;
sku = 888888;
})]
viewDidLoad:
let skuList = self.skuArray
for var i = 0; i < skuList.count ; ++i{
let extractedSku = skuList[i]!.value["sku"] as! String
// go into database and extract "products" details by sku
self.databaseRef.child("products/\(extractedSku)").observeEventType(.ChildAdded, withBlock: { (snapshot:FIRDataSnapshot) in
self.productDetailArray.append(snapshot)
})
Since the underlying type is NSNumber, use the stringValue property to get a String:
if let extractedSku = (skuList[i]?.value["sku"] as? NSNumber)?.stringValue {
// use extractedSku which is of type String
}
I am trying to get all the key values of NSMutableDictionary as String Array. I am using this myNSMutableDictionary.allkeys to get the values as an Array but I cannot find a way to unwrap the key values.
This is what I have tried so far:
for (key, _) in NSMutableDictionary {
println("THIS IS MY NEW KEY\(key)")
}
And I tried this
var myArray:NSArray = myNSMutableDictionary.allKeys
var string:NSString? = uniqueIDArray[0] as? NSString
println("This is unwraped value\(string!)")
And this
var myArray:Array = myNSMutableDictionary.allKeys
println("This is unwraped value\(myArray[0])")
I keep getting the value as Optional("kMSZgoTmiX") instead of kMSZgoTmiX which is the key value I need
Thank you for all your help!
So you've got a dictionary with values that are strings (and keys that are something, assume String):
var dictionaryOfStringValues : [String:String] = /* your dictionary */
And you want to iterate over the contents:
for (key, val) in dictionaryOfStringValues {
// use key and val
}
If you just want the values in a way you can easily iterate over:
var theValues = dictionaryOfStringValues.values
If you insist that theValues be an Array:
var theValuesAsAnArray = Array(dictionaryOfStringValues.values)
If you are starting with an NSMutableDictionary, then convert it at the point where it FIRST ENTERS your Swift code into a Swift Dictionary. Use an as variant to do that. After that, pure Swift.
Like this:
7> for (key, value) in ["a":1, "b":2] {
8. println (key)
9. println (value)
10. }
b
2
a
1
let myNSMutableDictionary = NSMutableDictionary()
myNSMutableDictionary["myKey1"] = 5
myNSMutableDictionary["myKey2"] = 10
myNSMutableDictionary["myKey3"] = 15
let myKeysArrayUnsorted = myNSMutableDictionary.allKeys as [String]
let myValuesArrayUnsorted = myNSMutableDictionary.allValues as [Int]
let keyString = myKeysArrayUnsorted[0] // "myKey2"
let keyValue = myNSMutableDictionary[keyString] as Int // 10
println("This is my first unsorted key \(keyString) = \(keyValue)")
let myKeysArraySorted = (myNSMutableDictionary.allKeys as [String]).sorted(<)
for key in myKeysArraySorted {
println(myNSMutableDictionary[key]!) // 5 10 15
}