var object1 = "C_active.scn"
var object86 = "Soap.scn"
var object41 = "image.scn"
var object9 = "NaCl.scn"
Name of different .SCN files
public func addBox(sceneView: ARSCNView) {
let imagePlaneScene = SCNScene(named: "art.scnassets/" + object1)
let imagePlaneNode = imagePlaneScene?.rootNode.childNode(withName: "object1", recursively: true)
imagePlaneNode?.position = positioner
I have a code reader that gives me a number and from that Int I have to place a specific .SCN file. I don't want to add 100 if statements like I do below. Is the some way to concatenate a string with a Int and turn that into a var in swift? (The numbers after each object is the number I receive from my code reader)
if(coding == 1) {
sceneView.scene.rootNode.addChildNode(imagePlaneNode!)
} else if(coding == 2) {
sceneView.scene.rootNode.addChildNode(imagePlaneNode!)
} else {
sceneView.scene.rootNode.addChildNode(imagePlaneNode!)
}
Something like
var("object" + coding) -> coding41 (Var)
Why don't you just use a dictionary to store your file names?
var object: [Int: String] = [1: "C_active.scn", 9: "NaCl.scn" ...]
When you need a particular filename, just use the number key attached to that string.
print(object[9]) //Prints "NaCl.scn"
Related
To search for a string included in a struct I use:
let results = myArray.filter( {$0.model.localizedCaseInsensitiveContains("bu")} )
But say the struct has several properties that I'd like to search - or maybe I'd even like to search all of them at one time. I can only filter primitive types so leaving 'model' out won't work.
Solution -------------------------
While I really liked the idea of using key paths as Matt suggested below, I ended up adding a function to my struct that made my view controller code much cleaner:
struct QuoteItem {
var itemIdentifier: UUID
var quoteNumber: String
var customerName: String
var address1: String
func quoteItemContains(_ searchString: String) -> Bool {
if self.address1.localizedCaseInsensitiveContains(searchString) ||
self.customerName.localizedCaseInsensitiveContains(searchString) ||
self.quoteNumber.localizedCaseInsensitiveContains(searchString)
{
return true
}
return false
}
Then, in my controller, quotes is an array of QuoteItem that I can search by simply writing:
searchQuoteArray = quotes.filter({ $0.quoteItemContains(searchString) })
This sounds like a job for Swift key paths. Just supply the key paths for the String properties you want to search.
struct MyStruct {
let manny = "Hi"
let moe = "Hey"
let jack = "Howdy"
}
let paths = [\MyStruct.manny, \MyStruct.moe, \MyStruct.jack]
let s = MyStruct()
let target = "y"
let results = paths.map { s[keyPath:$0].localizedCaseInsensitiveContains(target) }
// [false, true, true]
I hope i understood you correct. I think with this piece of code you can achieve what you want:
struct ExampleStruct {
let firstSearchString: String
let secondSearchString: String
}
let exampleOne = ExampleStruct(firstSearchString: "Hello", secondSearchString: "Dude")
let exampleTwo = ExampleStruct(firstSearchString: "Bye", secondSearchString: "Boy")
let exampleArray = [exampleOne, exampleTwo]
let searchString = "Hello"
let filteredArray = exampleArray.filter { (example) -> Bool in
// check here the properties you want to check
if (example.firstSearchString.localizedCaseInsensitiveContains(searchString) || example.secondSearchString.localizedCaseInsensitiveContains(searchString)) {
return true
}
return false
}
for example in filteredArray {
print(example)
}
This prints the following in Playgrounds:
ExampleStruct(firstSearchString: "Hello", secondSearchString: "Dude")
Let me know if it helps.
I'm working with Swift 3.
I would like to have this C syntax :
int myVar;
int *pointer = &myVar;
So modifying pointer or myVar does the same exact same thing.
Also I don't know if it makes any difference, but in my case myVar is an array containing elements of a class and pointer is a pointer to one element of this array.
The & also exists in Swift but can only be used as part of a parameter list (e.g. init, func, closure).
var i = 5
let ptr = UnsafeMutablePointer(&i)
print(ptr.pointee) // 5
// or
let ptr = UnsafeMutablePointer<Int>.allocate(capacity: 1)
ptr.initialize(to: 5)
// or with a closure
let ptr: UnsafePointer = { $0 }(&i)
(Assuming I understand what you're asking for....)
Try the following code in a playground. It should print "99" three times.
class Row {
var rowNumber = 0
}
var rows = [Row]()
let testRow = Row()
testRow.rowNumber = 1
rows.append(testRow)
let selectedRow = rows[0]
selectedRow.rowNumber = 99
print(testRow.rowNumber)
print(selectedRow.rowNumber)
print(rows[0].rowNumber)
By default, there's no copying of objects as part of an assignment statement. If it were a struct, that would be different.
Adding a bit for completeness:
If you want a similar effect with scalar values instead of objects, Swift supplies various types of wrappers.
let intPointer = UnsafeMutablePointer<Int>.allocate(capacity: 8) // Should be 1, not 8 according to comment re: docs
let other = intPointer
other.pointee = 34
print(intPointer.pointee)
(Warning: I haven't used these wrappers for anything except experimenting in a playground. Don't trust it without doing some research.)
Same example as #Phillip. But I used struct. In this example rows[0] won't change:
struct Row {
var rowNumber = 0
}
var rows = [Row]()
var testRow = Row()
testRow.rowNumber = 1
rows.append(testRow)
var selectedRow = rows[0]
selectedRow.rowNumber = 99
print(testRow.rowNumber) // prints 1
print(selectedRow.rowNumber) // prints 99
print(rows[0].rowNumber) // prints 1
There are no C style pointers (Unsafe Pointer) as the question asks however objects are shared by reference and structures are by value:
Swift assign, pass and return a value by reference for reference type and by copy for Value Type
structures are always copied when they are passed around in your code, but classes are passed by reference.
For example
How to have pointers/ references to objects
class Song {
init(title: String, image: String, file: String, volume: Float, queuePlayer: AVQueuePlayer, playerLooper: AVPlayerLooper?) {
self.title = title
self.image = image
...
}
var title: String
var image: String
...
}
var aSong = Song(title: "", image: "", ...)
var arrOfSongReferences: [Song] = [Song]()
arrOfSongReferences.append(aSong)
var ptrToASong: Song = aSong
aSong = nil
// Due to Swift garbage collection ARC (Automatic Reference Counting), we still have references to the original aSong object so it won't be deleted
If data is struct you cannot do this
struct Song {
var title: String
var image: String
...
}
var aSong: Song = Song(title: "", image: "", ...)
var copyOfASong: Song = aSong
Method
You can also pass by reference into a function
// this would be inside a class, perhaps Player. It doesn't have to be a static btw
static func playSound(_ sound: inout Song, volume: Float = 0.0) {
if (sound.playerLooper == nil) {
...
}
}
// usage
Player.playSound(sound: &aSong)
In my reflection library EVReflection I have the following problem when class definitions are nested (class within a class). Below is a worked out case which can be found as a unit test here and The location in the library itself where the code needs to change is Here
I need to get the Internal Swift string representation of a nested
class for a property which is an array of that nested class.
Below you can see a unit test where I am able to get the correct type for the property company that is an other object. It will output _TtCC22EVReflection_iOS_Tests13TestIssue114b10Company114 instead of Company114
When I try the same for the friends property my goal is that it outputs something like: Swift.Array<_TtCC22EVReflection_iOS_Tests13TestIssue114b7User114>
What do I have to do to get that?
As you can see in the test I have various assignments to the value valueType. None of these assignments work. I am only able to get an Array<User114> or an Swift._EmptyArrayStorage.
As you also can see in the test is that if I set a breakpoint and do a po in the output window I am able to get the correct output. So what code will accomplish the same in my code?
class TestIssue114b: XCTestCase {
class User114: EVObject {
var company: Company114 = Company114()
var friends: [User114] = []
}
class Company114: EVObject {
var name: String = ""
var address: String?
}
func testIssueNestedObjects() {
let x = User114()
print("type 1 = \(NSStringFromClass(type(of: x.company)))") // output = type 2 = _TtCC22EVReflection_iOS_Tests13TestIssue114b10Company114
print("type 2 = \(testIssueNestedObjects(x.friends))")
}
func testIssueNestedObjects(_ theValue: Any) -> String {
var valueType = ""
let mi = Mirror(reflecting: theValue)
valueType = NSStringFromClass(type(of: (theValue as! [NSObject]).getTypeInstance() as NSObject)) // NSObject
valueType = "\(type(of: theValue))" // Array<User114>
valueType = "\(mi.subjectType)" // Array<User114>
valueType = ObjectIdentifier(mi.subjectType).debugDescription //"ObjectIdentifier(0x0000000118b4a0d8)"
valueType = (theValue as AnyObject).debugDescription // <Swift._EmptyArrayStorage 0x10d860b50>
valueType = NSStringFromClass(type(of: theValue as AnyObject)) // Swift._EmptyArrayStorage
// set breakpont en enter this in output window: (lldb) po type(of: theValue)
// Ouput will be: Swift.Array<EVReflection_iOS_Tests.TestIssue114b.User114>
return valueType
}
}
Background info:
Actually the end goal is that I have to be able to create instances of the object that I can add to the array. Since the array property is only available as a result from a Mirror command the variable will be of type Any. I do have an extension for arrays in place that will return a new array element. however I am only able to get that when the Any is casted to Array<NSObject> and because of that my extension will return an NSObject. So I would like to get a string like Swift.Array<_TtCC22EVReflection_iOS_Tests13TestIssue114b7User114> I can then get the parts between <> and then create an instance for that using NSClassFromString.
String(reflecting: type(of: theValue))
update by Edwin Vermeer:
For the required conversion to the internal string representation i now have the following function (still in draft)
public class func convertToInternalSwiftRepresentation(type: String) -> String {
if type.components(separatedBy: "<").count > 1 {
// Remove the Array or Set prefix
let prefix = type.components(separatedBy: "<") [0] + "<"
var subtype = type.substring(from: prefix.endIndex)
subtype = subtype.substring(to: subtype.characters.index(before: subtype.endIndex))
return prefix + convertToInternalSwiftRepresentation(type: subtype) + ">"
}
if type.contains(".") {
var parts = type.components(separatedBy: ".")
if parts.count == 2 {
return parts[1]
}
let c = String(repeating:"C", count: parts.count - 1)
var rv = "_Tt\(c)\(parts[0].characters.count)\(parts[0])"
parts.remove(at: 0)
for part in parts {
rv = "\(rv)\(part.characters.count)\(part)"
}
return rv
}
return type
}
I am trying to create dynamic struct in swift based on user input.
struct Diagnosis {
var diagName = String() // Name of the diagnosis
var diagSymptoms = [String]() // Symptoms of the diagnosis in a ranked array to identify prevelancy
var diagSpecialization = [String]() // the specializations which would mostly encounter this diagnosis
var diagRank = Int() // the overall rank of the diagnosis
var diagSynonoms = [String]() // the other name thru which the same diagnosis is called / referred.
// func init(diagName: String(),diagSymptoms: [String](),diagSpecialization: [String](),diagSynonoms: [String]())
init( let pasdiagName: String,let pasdiagSymptoms:Array<String>) {
self.diagName = pasdiagName
self.diagSymptoms = pasdiagSymptoms
}
}
var maleria = Diagnosis(pasdiagName: "Maleria",pasdiagSymptoms: ["fever","chill","body pain"])
The above creates the structure maleria - But in future I want to have the input from user and create a structure for that inputted string
var abc = "typhoid"
let valueof(abc) = Diagnosis()
The value of function is something I just put here arbitrarily to make my explanation clear.
I know I could do this in python and I am new to swift. Thanks in advance for the help.
As #Wain suggested, you should use a Dictionary.
This is how you create a mutable dictionary where the key is a String and the value can be any type.
var dict = [String:Any]()
This is how you put key/value pairs into the dictionary
dict["year"] = 2016
dict["word"] = "hello"
dict["words"] = ["hello", "world"]
And this is how you extract a value and use it
if let word = dict["word"] as? String {
print(word) // prints "hello"
}
Why is the realm-list containing the very same elements instead of different ones ?
As you can see in the picture below, there are two relam-objects (UndoMemoryNameEntry and NameEntry). The first one contains a list of 8 elements. The list's element-type is of type NameEntry !
My last NameEntry object is written with currentScorePlayer=1 and currentScoreMe=15 as you can see in the picture below:
The list in UndoMemoryNameEntry is correctly inserted the last NameEntry object. You find the insertion-code further down...
But now the problem: Why are all the existing list-elements as well changed to the newest inserted element ???? As you can see in the picture below, all the elements are unfortunately identical to the last one added - why ??????
If I change the NameEntry to the following :
And inserting at index=0 to the list, then the List changes to :
Why are all the elments changed ? And not just the inserted one ??? Thanks for any help on this !
My two realm-objects are :
class NameEntry: Object {
dynamic var playerName = ""
dynamic var isMyAdversary: Bool = false
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
}
and the List :
class UndoMemoryNameEntry: Object {
dynamic var undoPlayerName = ""
let NameEntryList = List<NameEntry>()
}
The following code creates the Realm-List :
// query rlm for existing object (with name adversary
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", adversaryName)
let undoPlayerName = rlm.objects(UndoMemoryNameEntry).sorted("undoPlayerName", ascending: true).filter(undoPredicate)
// if undoPlayerName object does not exist - then create it!
if (undoPlayerName.count < 1) {
rlm.beginWrite()
let undoEntry = UndoMemoryNameEntry()
undoEntry.undoPlayerName = adversaryName
rlm.add(undoEntry)
rlm.commitWrite()
}
The following code adds a "NameEntry"-Element in the List :
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", plaNameLab)
let undoPlayerName = rlm.objects(UndoMemoryNameEntry).sorted("undoPlayerName", ascending: true).filter(undoPredicate)
if (undoPlayerName.count == 1) {
rlm.beginWrite()
println(entry)
var undoEntry = undoPlayerName[0] as UndoMemoryNameEntry
undoEntry.NameEntryList.insert(entry, atIndex: 0)
rlm.commitWrite()
}
The above code-excerts work perfectly - except that the realm-List always changes all its elements to the one just inserted.
I finally found a solution:
First of all rearrange the two realm objects as follows:
class NameEntry: Object {
dynamic var playerName = ""
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
// the undo-list is better placed in the first object...
let undoEntryList = List<UndoMemoryNameEntry>()
override static func primaryKey() -> String? {
return "playerName"
}
}
class UndoMemoryNameEntry: Object {
dynamic var undoPlayerName = ""
dynamic var currentScorePlayer: Int = 0
dynamic var currentScoreMe: Int = 0
// no primary key here since the undoEntry will have several items with the same undoPlayerName
}
Then when adding a "NameEntry"-Element in the List :
let predicate = NSPredicate(format: "playerName == %#", plaNameLab)
let playerName = rlm.objects(NameEntry).sorted("playerName", ascending: true).filter(predicate)
if (playerName.count == 1) {
rlm.beginWrite()
var entry = playerName[0] as NameEntry
// you need to create a new list object first !!!!!!!!!!!!
// ...in my initial example, this creation was missing !!!!!!
var siblingEntry = UndoMemoryNameEntry()
siblingEntry.undoPlayerName = plaNameLab
siblingEntry.currentScorePlayer = entry.currentScorePlayer
siblingEntry.currentScoreMe = entry.currentScoreMe
// insert new list-element
entry.undoEntryList.insert(siblingEntry, atIndex: 0)
// alternatively choose append if you want to add the element at the end of the list
entry.undoEntryList.append(siblingEntry)
// or choose the "ringbuffer-solution" given in the add-on below if you want to restrict the number of list-elements to ringbuffer-size !
// ...
rlm.commitWrite()
}
Add-on: If you want to create a ringbuffer having only a limited number of list-elements:
// create ringbuffer of 20 elements (20th element will be newest)
let ringBufferSize = 20
let undoPredicate = NSPredicate(format: "undoPlayerName == %#", plaNameLab)
if (entry.undoEntryList.filter(undoPredicate).sorted("undoPlayerName").count < ringBufferSize) {
entry.undoEntryList.append(siblingEntry)
}
else {
// entry.undoEntryList.replace(ringBufferSize-1, object: siblingEntry)
entry.undoEntryList.removeAtIndex(ringBufferSize-1)
entry.undoEntryList.append(siblingEntry)
for index in 0..<ringBufferSize-1 {
let tempEntry1 = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[index] as UndoMemoryNameEntry
let tempEntry2 = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[index+1] as UndoMemoryNameEntry
tempEntry1.currentScorePlayer = tempEntry2.currentScorePlayer
tempEntry1.currentScoreMe = tempEntry2.currentScoreMe
}
let tempEntry = rlm.objects(UndoMemoryNameEntry).filter(undoPredicate).sorted("undoPlayerName")[ringBufferSize-1] as UndoMemoryNameEntry
rlm.delete(tempEntry)
}