I'm writing a PDF Parser in Swift and I've reached the point where I get all the font data with a callback function (CGPDFDictionaryApplyFunction), the getFont function is supposed to populate the fonts dictionary in the PDFFontCollection class.
Inside the "getFont" callback function the collection variable is correctly populated - however when the callback is finished the fonts dictionary has still 0 entrys.
class PDFFontCollection{
var fonts: [AnyHashable:Any]!
init(page: CGPDFPage){
fonts = [AnyHashable:Any]()
let fontsdict = self.findFontDictionary(page: page)
if(fontsdict != nil){
CGPDFDictionaryApplyFunction(fontsdict!, self.getFont , &self.fonts)
}
}
private var getFont: CGPDFDictionaryApplierFunction = { (key, object, info) in
var collection = info?.assumingMemoryBound(to: [AnyHashable: Any].self).pointee
var name = String(cString: key, encoding: String.Encoding.ascii)
var dict: CGPDFDictionaryRef?
if (CGPDFObjectGetValue(object, .dictionary, &dict)){
var font = PDFFont.pdfFont(withFontDictionary: dict!)
collection?.updateValue(font!, forKey: name!)
}
}
For whoever may be interested, PeejWeej is right. You need to declare fonts as an NSMutableDictionary in order to be able to populate it, since [AnyHashable:Any] is always passed by reference.
Related
Is it possible to add a dynamic amount of strings to Firestore?
This is my code:
I use a string array called names.
let newDoc = ref.collection("Docs").document()
for i in 0 ..< names.count{
newDoc.setData(["\(i)" : names[i]])
}
It's possible, but you probably don't want to be calling setData repetitively like that. Instead, you can translate names into a Dictionary<String,String> and then just call setData once:
let names = [String]()
let dictVersion = Dictionary(uniqueKeysWithValues: names.enumerated().map { index, value in
return ("\(index)",value)
})
let newDoc = ref.collection("Docs").document()
newDoc.setData(dictVersion)
Hello I have a json the returns me some parameters as variables.
It has Parameter1, Parameter2, Parameter3 etc..
I don't know how many parameters will it give me. It's not a list it's just different variables in the json.
Which is the best way to map a json like that? I use Object Mapper
For Example:
First Time the json is
{
"MyObject": {
"Parameter1": "p1",
"Parameter2": "p2",
"Parameter3": "p3",
"Parameter4": "p4"
}
}
And a second time the json is
{
"MyObject": {
"Parameter1": "p1",
"Parameter2": "p2",
"Parameter3": "p3"
}
}
You can try this.
let keyvalue = parentDict.value(forKey: "MyObject") as! NSDictionary
var lastValue = Keyvalue.allValues
var lastKey = Keyvalue.allKeys
for Keyname in Keyvalue.allKeys
{
print("Keyname %#",Keyname)
print("Value %#",Keyvalue.value(forKey:Keyname))
}
the first step to parse any JSON to make it reusable is to create your Model class or struct accordingly.
Create a class called MyObject as same as your json dictionary
Create a let/var property parameters: [String]?. It's optional as API isn't reliable and maybe wont send anything at all.
See the example below how I parse the json object below.
class MyObject {
let parameters: [String]?
// it's failable because maybe json different at runtime & couldn't parse
init?(json: [String:AnyObject]) {
var key = "Parameter"
var parms = [String]()
for i in 0..<json.count {
guard let item = json["\(key)\(i+1)"] as? String else { continue }
params.append(item)
}
self.parameters = params
}
}
Now you can access the parameters array with index.
Well this could be refactored and you can get the idea how you will handle this with that library.
I have a Dictionary and i want to save it to NSUserDefaults(or something else so I can have access to my variables after i have terminated the app) , I found an example:
var saved = NSUserDefaults.standardUserDefaults()
let dict = ["Name": "Paul", "Country": "UK"]
saved.setObject(dict, forKey: "SavedDict")
But when i used it to mine Dictionary it didn't work. (maybe because my dictionary it's a little bit different)
My Dictionary is made like this:
var userDictionary = [Int : Event]()
struct Event {
var sensorName: String
var sensorType: String
var sensorSub: String
}
And i add elements like this:
userDictionary[value] = Event(sensorName: "first", sensorType: "Temp", sensorSub: "Third")
And here is what i tried to do so I can store it.
saved.setObject(userDictionary, forKey: "valueDictionary")
And I get this error:
Cannot convert value of type '[Int : SensorsView.Event]' to expected
argument type 'AnyObject?'
To avoid this error I did this:
self.saved.setObject(self.userDictionary as? AnyObject, forKey: "valueDictionary")
But I can't retrieve what i saved
Unfortunately this question didn't help me after some comments i believe that the goal here is to convert my dictionary to Data (or something else) and after i retrieve it i convert it back to Dictionary
Try to convert the data to NSData and then retrieve like so:
/// Save
NSUserDefaults.standardUserDefaults().setObject(NSKeyedArchiver.archivedDataWithRootObject(object), forKey: key)
/// Read
var data = NSUserDefaults.standardUserDefaults().objectForKey(key) as NSData
var object = NSKeyedUnarchiver.unarchiveObjectWithData(data) as [String: String]
What i think is from the link below you will be able to store the Dictionary into NSUserDefaults
Swift NSUserDefaults not saving Dictionary?
or
Saving dictionary into NSUserDefaults may help
I managed to save my custom Dictionary using Realm!
Instead of a struct I use a different class like this:
import RealmSwift
class Sensors : Object {
dynamic var sensorName = ""
dynamic var sensorType = ""
dynamic var sensorSub = ""
}
and then I fill it like this:
var useOfRealm = try! Realm()
var allSensors = useOfRealm.objects(Sensors.self)
var saving = Sensors()
func fillThis() {
try! useOfRealm.write {
saving.sensorName = "something"
saving.sensorType = "something"
saving.sensorSub = "something"
useOfRealm.add(saving)
}
}
Use the function with parameters so you can fill the 'Dictionary' Dynamically.
Use allSensors so you can retrieve everything that you want.
I have a Dictionary that holds another Dictionary that holds an Array which holds another Array of a custom class. I'm having a lot of trouble working with these can someone who this comes easy to tell me the ways I can define, initialize, and access and assign to either part specifically.
Dic = [String: [String: [[MyClass]]]]
Sorry if it's confusing.
This code shows you how to do what you asked, but the data structure you requested is quiet cumbersome to use. I'll recommend to think again about what you want to accomplish and review this data structure.
class MyClass {
var name : String
init(name: String) {
self.name = name
}
}
// Create your dictionary
var dic : [String: [String: [[MyClass]]]] = [:]
// Create a list of MyClass object
var list = [MyClass(name: "first"), MyClass(name: "second"), MyClass(name: "third")]
// Create a dictionary with string key and array of array of type MyList
var myClassDic = ["test": [list]]
// update or add new value via the updateValue method
dic.updateValue(myClassDic, forKey: "index1")
// update or add new value via the subscript
dic["index2"] = ["test2": [[MyClass(name: "forth"), MyClass(name: "fith")]]]
// Iterate over your outer dictionairy
for key in dic.keys {
// retrieve an entry from your outer dictionary
var tempDic = dic[key]
// Iterate over your inner dictionary
for sKey in tempDic!.keys {
// retrieve an array of array of MyList Object
var containerList = tempDic![sKey]
// iterate over the outer array
for listVal in containerList! {
//Iterate over the inner array
for sListVal in listVal {
print("\(sListVal.name) ")
}
println()
}
}
}
I have a dictionary set up as:
var jDict = Dictionary<String, AnyObject[]>()
Where the arrays are either a collection of custom buttons (JunkButton) or Labels (JunkLabels).
I am having an issue when trying to access the members of the arrays contained in the Dictionary as follows:
let thisArray = jDict[key]
var aButton = thisArray[0] //Gives error: 'AnyObject[]? does not have a member named 'subscript'
I can get around this by downcasting the whole array as follows:
if let aArray = thisArray as? JunkButton[]{
var aButton = aArray[0]
}
This seems very cumbersome especially if I am sure I know what type the array is made up of beforehand. Is there a way to cast thisArray when it is created that would allow me to extract its elements without unwrapping them each time?
Dictionary always give you Optional value.
Your code is like this
let thisArray : Optional<AnyObject[]> = jDict[key]
You need to unwrap it to get non-optional value
let thisArray = jDict[key]! // thisArray is AnyObject[]
You really shouldn't use a dictionary for this. Swift makes it very easy to use custom little structs or classes instead of dictionaries:
struct JunkItems {
var buttons: [JunkButton] = []
var labels: [JunkLabel] = []
}
Then you can access those items like this without downcasting:
for button in junkItems.buttons {
// ...
}
Or:
if let button = junkItems.buttons[0] {
// ...
}
Btw, the array notation [JunkButton] is new in beta 3.