I created an array of dictionary, but I have an error, when I tried to add my object (a dictionary) to my array.
I have this error "AnyObject does not have a member named 'append'"
var posts=[Dictionary<String,AnyObject>]()
var post=Dictionary<String,AnyObject>()
var attachment=Dictionary<String,AnyObject>()
...
post=["id":"a", "label":"b"]
attachment=["id":"c", "image":"d"]
var newPost = [post, attachment]
posts.append(newPost) <- AnyObject does not have a member named 'append'
I don't understand. Maybe I haven't initialize the array correctly ?
UPDATE / SOLVED
var posts=[Dictionary<String,Dictionary<String,AnyObject>>]()
var post=Dictionary<String,AnyObject>()
var attachment=Dictionary<String,AnyObject>()
...
post=["id":"a", "label":"b"]
attachment=["id":"c", "image":"d"]
var newPost = ["post":post, "attachment":attachment]
posts.append(newPost) <- AnyObject does not have a member named 'append'
EDIT : newPost is a instance of dictionary and posts an array of dictionaries
append is to add an item, whereas you are trying to append another array (post is an array of dictionaries). You can use the += operator:
posts += newPost
or use the extend method (which is equivalent to the += operator):
posts.extend(newPost)
or add elements individually:
posts.append(post)
posts.append(attachment)
If you want each post to be an array of post and argument:
var posts=[[Dictionary<String,AnyObject>]]()
Also, you can define the type for post and attachment without creating empty objects:
var post:Dictionary<String,AnyObject>
var attachment:Dictionary<String,AnyObject>
Related
I am pushing an object into an array but cannot do it?
I'm doing it like this
this.passData = this.tribeForm.value;
var id = {"tribe_id": 1}
this.passData.push(id)
This is the value in the tribeForm
I also tried
var id = {tribe_id: 1}
and
this.passData.splice(0,0, id)
and
this.passData = Array.prototype.slice(id)
and
this.passData.concat(id)
but it all ends up with
TypeError: this.passData.push/splice/concat is not a function
The question is not that clear, But I understood you are manipulating form data, value of form data returns an Object, Not an array. Objects in JavaScript are represented as key-value pairs, (or attribute-value) pairs.
Example :
var object = {
name : "Jhon",
grade : 12,
gpa : 8.12
}
It is just a collection of key-value pairs, push(), concat() and other methods are supported only for Arrays not for Objects. You can achieve whatever you want simply by creating a new key/attribute and assigning the value to it.
this.passData = this.tribeForm.value
this.passData['tribe_id'] = 1
//or, Objects can also contain nested object
this.passData['someKey'] = {'tribe_id' : 1}
You can create an empty array and push objects to it
Example :
var exampleArray = []
exampleArray.push({'tribe_id' : 1})
Now, it works because exampleArray is an Array not JS object.
Thanks for A2A
First, you need to understand the error:
TypeError: this.passData.push/splice/concat is not a function
Push/splice/concat is functions for Array and because of that the console is yelling at you that the passData is not an Array.
Make sure your passData is an Array and you will able to do so.
I ran into an issue with arrays in Swift. The problem is that it's a value type in Swift. I'm trying to find a workaround.
Here is the code that I have:
class Object: Codable{
var name : String?
}
var objects: Array<Object>?
objects = Array<Object>()
if var obj = objects { // <----- Creates a copy of array here
let o = Object()
o.name = "1"
objects?.append(o)
print(obj) //<----- this one is missing "o" object
print(objects)
}
I cannot use NSMutableArray because I have an array inside another codable class.
What's everybody's experience on this one? If somebody can share a solutions for that.
Getting used to arrays as value types isn't too tough really. If i were you my version of the code would just look like this
var objects: Array<Object>?
objects = Array<Object>()
if var unwrappedObjs = objects {
let o = Object()
o.name = "1"
unwrappedObjs.append(o)
objects = unwrappedObjs
}
or alternatively maybe this:
var objects: Array<Object>?
objects = Array<Object>()
if objects != nil {
let o = Object()
o.name = "1"
objects?.append(o)
}
Lastly you could always try making your own "ReferenceArray" class that wraps the array APIs and gives you reference semantics but that seems like overkill. Sooner rather than later, arrays as value types will seem natural to reason about.
bitwit already mentioned this to a point, but I think that your biggest mistake is simply not accepting the new object as the source. Unless it's important to retain the Array<Object>? you should replace it with the Array<Object> one.
var objects: Array<Object>?
objects = Array<Object>()
if var objects = objects { // <----- Creates a copy of array here
let o = Object()
o.name = "1"
objects.append(o) // objects is now the non-optional one
print(objects)
}
If it needs to be in the same scope, use guard:
var objects: Array<Object>?
objects = Array<Object>()
guard var objects = objects else { // <----- Creates a copy of array here
fatalError()
}
let o = Object()
o.name = "1"
objects.append(o) // objects is now the non-optional one
print(objects)
If you absolutely need an array to be referenced, you can make a container class:
public class ReferenceContainer<Element> {
public var element: Element
init(_ element: Element) {
self.element = element
}
}
I am currently struggling with obtaining a value from an array inside an array of dictionaries. Basically I want to grab the first "[0]" from an array stored inside an array of dictionaries. This is basically what I have:
var array = [[String:Any]]()
var hobbies:[String] = []
var dict = [String:Any]()
viewDidLoad Code:
dict["Name"] = "Andreas"
hobbies.append("Football", "Programming")
dict["Hobbies"] = hobbies
array.append(dict)
/// - However, I can only display the name, with the following code:
var name = array[0]["Name"] as! String
But I want to be able to display the first value in the array stored with the name, as well. How is this possible?
And yes; I know there's other options for this approach, but these values are coming from Firebase (child paths) - but I just need to find a way to display the array inside the array of dictionaries.
Thanks in advance.
If you know "Hobbies" is a valid key and its dictionary value is an array of String, then you can directly access the first item in that array with:
let hobby = (array[0]["Hobbies"] as! [String])[0]
but this will crash if "Hobbies" isn't a valid key or if the value isn't [String].
A safer way to access the array would be:
if let hobbies = array[0]["Hobbies"] as? [String] {
print(hobbies[0])
}
If you use a model class/struct things get easier
Given this model struct
struct Person {
let name: String
var hobbies: [String]
}
And this dictionary
var persons = [String:Person]()
This is how you put a person into the dictionary
let andreas = Person(name: "Andreas", hobbies: ["Football", "Programming"])
persons[andreas.name] = Andreas
And this is how you do retrieve it
let aPerson = persons["Andreas"]
I am new to Swift.
I am trying to get some data from a webservice and to loop the JSON data to make a simple array.
DataManager.getDataFromEndpoint{ (endpointData) -> Void in
let json = JSON(data: endpointData)
if let programsOnAir = json["data"]["data"]["on_air"].array{
var onAirArray = []
for onAir in programsOnAir {
var eventName = onAir["event_name"].string
var eventCover = onAir["event_cover"].string
var tuple = (name: eventName!, cover: eventCover!)
onAirArray.insert(tuple, atIndex: 1)
}
println(onAirArray)
}
}
I get an error where the member .insert does not exist
BUt if I init the array like this var onAirArray = [name: "something, cover: "somethingelse"] then it works.
I need to work with empty arrays and I need to be them mutable, because I have no idea what I may get from the JSON given by the API endpoint.
What am I doing wrong?
The problem is with this line:
var onAirArray = []
Since you haven't given the array an explicit type, this is creating a new instance of NSArray, which doesn't have a method called insert. Which is why this is probably the exact error message you're receiving.
'NSArray' does not have a member named 'insert'
To fix this, explicitly state the type of your array.
var onAirArray: [(String, String)] = []
Is it possible to access a string inside an array that is inside another array? - Swift
for instance:
var a = 1
var b = 2
var maleDogs = ["Fido","Thor"]
var femaleDogs = ["Linn","Eva"]
var dogs = [maleDogs,femaleDogs]
And then do something like
dogs[a][b]
In this instance, I wanted to get "Thor" as an output, but it calls an error. (Inside playground)
Your code is completely correct, but note that Swift array indices are zero-based, so accessing index 2 causes an "Array index out of range" exception.
You can see the error message if you open the "Assistant Editor" for the Playground file
(View -> Assistant Editor -> Show Assistant Editor).
What you probably wanted is
var a = 0
var b = 1
var maleDogs = ["Fido","Thor"]
var femaleDogs = ["Linn","Eva"]
var dogs = [maleDogs,femaleDogs]
dogs[a][b] // Thor