I'm new to RxSwift and reading about subjects, I tried Variable Subject. Which in turns giving Warning in console
ℹ️ [DEPRECATED] `Variable` is planned for future deprecation. Please consider `BehaviorRelay` as a replacement. Read more at: https://git.io/vNqvx
Earlier I have declared Variable like this
var searchItems = Variable<[MyClass]>([])
So i have done basic array operations from it's property called value as it was get set property like
1. self.searchItems.value.removeAll()
2. self.searchItems.value.append(items)
3. self.searchItems.value = items
Now After getting warning i changed it to BehaviorRelay like
var searchItems = BehaviorRelay<[MyClass]>(value: [])
So I got error that value is get property only.
I googled alot but can't get suitable explanations for Array operations.
I only got a code self.searchItems.accept(items) which i really don't know what it exactly do add fresh items or append.
I needed how all 4 operations will be performed when using BehaviorRelay?
1) Remove all
var array = self.searchItems.value
array.removeAll()
self.searchItems.accept(array)
2) Append item
self.searchItems.value.accept(searchItems + [items])
3) Value = ...
self.searchItems.value.accept(items)
Use accept.
var value = searchItems.value
value.removeAll()
searchItems.accept(value)
etc...
Related
I have an C API I need to interact with in Swift.
One of the function takes an array of pointers as argument, which is imported by Swift as
`UnsafeMutablePointer<UnsafeMutablePointer<Float>?>! `
The corresponding input on the Swift side is AVAudioPCMBuffer.floatChannelData, which is defined as
UnsafePointer<UnsafeMutablePointer<Float>>?
I am having trouble casting between the two.
I tried to make it mutable by doing following:
UnsafeMutablePointer<UnsafeMutablePointer<Float>>(AVAudioPCMBuffer.floatChannelData)
And that did not work. The casting between Swift pointer types are very frustrating. Any help will be really appreciated.
Thanks
var testPtr : UnsafeMutablePointer<UnsafeMutablePointer<Float>?>! = nil
var testPtr2 : UnsafePointer<UnsafeMutablePointer<Float>>? = nil
testPtr = unsafeBitCast( testPtr2, to: UnsafeMutablePointer<UnsafeMutablePointer<Float>?>!.self)
As per excellent #easytarget suggestion since XCode 13.3 use modern syntax instead (not generating a warning):
testPtr = UnsafeMutablePointer(mutating: testPtr2)
The following code used to work, but now when I try and use the code I'm getting an error stating, "Ambiguous reference to member 'append'". Any ideas?
var allInfo: Array = [[String]]()
let Dogs : Array = ["Border Collie","Doberman", "German Shepherd"]
let Cats : Array = ["Top Cat","Tom"]
allInfo.append(Dogs)
allInfo.append(Cats)
I've changed the name of the allInfo variable to myPets to see if it that was the problem and updated to Xcode 7.1.1 but still getting the following error. Although it works in playground. Very frustrating.
Thanks for all the support. I got this working by explicitly adding the type of each array as follows:
let Dogs : Array<String> = ["Border Collie","Dobermann", "German Shepherd"]
And I had to remove the : Array from my multidimensional arrays like so:
var myPets = [[String]]()
I don't know if this is an Xcode bug but hopefully my answer may help others in our community.
You most likely have a different definition of either the allInfo variable or the elements you are adding. Make sure you do not have duplicates of those.
I'm developing an app using Grails. I want to get length of array.
I got a wrong value. Here is my code,
def Medias = params.medias
println params.medias // I got [37, 40]
println params.medias.size() // I got 7 but it should be 2
What I did wrong ?
Thanks for help.
What is params.medias (where is it being set)?
If Grials is treating it as a string, then using size() will return the length of the string, rather than an array.
Does:
println params.medias.length
also return 7?
You can check what Grails thinks an object is by using the assert keyword.
If it is indeed a string, you can try the following code to convert it into an array:
def mediasArray = Eval.me(params.medias)
println mediasArray.size()
The downside of this is that Eval presents the possibility of unwanted code execution if the params.medias is provided by an end user, or can be maliciously modified outside of your compiled code.
A good snippet on the "evil (or lack thereof) of eval" is here if you're interested (not mine):
https://javascriptweblog.wordpress.com/2010/04/19/how-evil-is-eval/
I think 7 is result of length of the string : "[37,40]"
Seems your media variable is an array not a collection
Try : params.medias.length
Thanks to everyone. I've found my mistake
First of all, I sent an array from client and my params.medias returned null,so I converted it to string but it is a wrong way.
Finally, I sent and array from client as array and in the grails, I got a params by
params."medias[]"
List medias = params.list('medias')
Documentation: http://grails.github.io/grails-doc/latest/guide/single.html#typeConverters
Another ameture hour Swift Programming Question.
I have been returning values for an object from an array of object "Any Object" "Results". The intellitype says I have an object in the array with a value "ContactUID" however when I try to use ContactUID I get an error saying 'AnyObject' Doesn't contain member 'contactUID'.
The Array called HBCContactList successfully returns, FirstName, LastName and all the other items listed on the screen in the code. However it Will not return the Value 'ContactUID'.
The Model has got the right item. However unlike all the others... ContactUID is a INT64 instead of a string... I have added some screenshots to assit with the process of explaining. Sorry it sounds complicated but I expect I am missing something stupid.
Autocomplete on iOS isn't always accurate, often it will just list all possible selectors / methods.
The root of your problem here is that even though you know HCCContactList holds only HBCDirectoryModel objects, the compiler doesn't as MOContext.executeFetchRequest(freq, error: nil) returns an Array which declares it contains AnyObject's ([AnyObject] / Array<AnyObject>). In order to refer to any of these objects as an HBCDirectoryModel you'll need to conduct a cast to this type.
The easiest way to do this is is to declare your HCCContactList as being an array of HBCDirectoryModel's instead of AnyObject's, and then casting the result of calling MOContext.executeFetchRequest() to this same type.
You can do this as follows
var HCCContactList: Array<HBCDirectoryModel> = []
HCCContactList = MOContext.executeFetchRequest(freq, error: nil) as Array<HBCDirectoryModel>
Or using the shorter syntax
var HCCContactList:[HBCDirectoryModel] = []
HCCContactList = MOContext.executeFetchRequest(freq, error: nil) as [HBCDirectoryModel]
Hi all real newbie question here.
I have an array like this:
var daysInMonth = Array<([MyCustomClass], NSDate)>()
How can I append an element to this?
I am having difficulty doing so. Trying something like this:
daysInMonth.append([MyCustomClass](), someDate)
or
daysInMonth.append( ([MyCustomClass](), someDate) )
will not work (i'd like to add an empty array initial above of type MyCustomClass, as well as some date that I have) but these are failing (error missing parameter #2 in call)
Any thoughts on what I am lacking in my syntax?
Thanks!
It looks like a swift bug to me. The swift compiler cannot correctly parse the "( (...) )" as passing in a tuple to a function.
If I break the append operation into two statements, it works.
var daysInMonth = Array<([MyCustomClass], NSDate)>()
let data = ([MyCustomClass()], NSDate()) // assuming MyCustomClass init() taks no parameter
daysInMonth.append(data)
note: It was [MyCustomClass]() in your question, which is incorrect.
Try declaring your array using the newer Array syntax instead:
var daysInMonth = [([MyCustomClass], NSDate)]()
Then, this works:
daysInMonth.append(([MyCustomClass](), NSDate()))