I'm trying to make the conversion from Objc to swift and have had better days.
I have a class with a dictionary:
collaborationDictionary:[String:Set<String>]
I am trying to write/read this dictionary to/from a file and just can't quite seem to make it work. I have to save the dictionary using the following JSON structure and I have to use SwiftyJSON.
{ "Collaborations" : {
"5604" : [
"whiteboard.png",
"VID_20161123_135117.3gp",
"Photo_0.jpeg"]
"5603" : [
"VID_20161123_135117.3gp"],
"5537" : [
"Screenshot_20151212-132454.png",
"VID_20161202_083205.3gp",
"VID_20161123_135117.3gp",
"Photo_0.jpeg",
"Screenshot_20151212-132428.png",
"Screenshot_20151212-132520.png",
"IMG_20161017_132105.jpg",
"whiteboard.png"]}
}
I don't have any real problem with finding/retrieving the file or writing the file. I just can't quite figure out how to manually load SwiftyJSON. I need to have a JSON object called "Collaborations" at the top. It needs to contain a dictionary of collaboration IDs (5604, 5603...). Each collaboration contains an array of string (filenames). I'm including the code I'm using to read/write the file but I need help with the SwiftyJSON library.
This is the member data member I'm using to store the above data:
These are the functions I need to finish:
private var collaborationDictionary:[String:Set<String>] = [:]
func getUploadedFileSet() {
collaborationDictionary = [:]
let documentsURL = URL(string: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let appURL = documentsURL?.appendingPathComponent(APP_DISTINGUISHED_NAME)
let jsonFileURL = appURL?.appendingPathComponent(UPLOADED_ITEMS_DB_JSON)
if FileManager.default.fileExists(atPath: (jsonFileURL?.absoluteString)!) {
do {
let data = try Data(contentsOf: jsonFileURL!, options: .alwaysMapped)
let json = JSON(data: data)
// ************************************************
// NEED HELP START
// NOW WHAT???? What is the SwiftyJSON code
?????????????????????????
// NEED HELP END
// ************************************************
} catch let error {
print(error.localizedDescription)
}
}
}
func saveUploadedFilesSet() {
let documentsURL = URL(string: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let appURL = documentsURL?.appendingPathComponent(APP_DISTINGUISHED_NAME)
let jsonFileURL = appURL?.appendingPathComponent(UPLOADED_ITEMS_DB_JSON)
do {
let dirExists = FileManager.default.fileExists(atPath: (appURL?.absoluteString)!)
if !dirExists {
try FileManager.default.createDirectory(atPath: (appURL?.absoluteString)!, withIntermediateDirectories: false, attributes: nil)
}
// ************************************************
// NEED HELP START
// NOW WHAT???? What is the SwiftyJSON code
?????????????????????????
// NEED HELP END
// ************************************************
// Write to file code - haven't written it yet but that should be easy
} catch let error as NSError {
print(error.localizedDescription);
}
}
Any direction would be greatly appreciated. Thanks!
EDIT
I was able to figure out how to load the supplied JSON structure from file. Here is the code:
func getUploadedFileSet() {
let documentsURL = URL(string: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let appURL = documentsURL?.appendingPathComponent(APP_DISTINGUISHED_NAME)
let jsonFileURL = appURL?.appendingPathComponent(UPLOADED_ITEMS_DB_JSON)
if FileManager.default.fileExists(atPath: (jsonFileURL?.absoluteString)!) {
do {
let data = try Data(contentsOf: jsonFileURL!, options: .alwaysMapped)
let json = JSON(data: data)
if json != nil {
for (key, subJson) in json[kCollaborations] {
let stringArray:[String] = subJson.arrayValue.map { $0.string! }
let stringSet = Set(stringArray)
collaborationDictionary.updateValue(stringSet, forKey: key)
}
} else {
print("Could not get json from file, make sure that file contains valid json.")
}
} catch let error {
print(error.localizedDescription)
}
}
I still haven't figured out how to save the collaborationDictionary object to file. My biggest problem is figuring out how to put in the "Collaborations" key. Any ideas?
I finally got this to work. The biggest problem was that I couldn't convert collaborationDictionary to JSON. I finally had to convert it to a dictionary of arrays vs dictionary of sets. Here are the 2 methods:
// **************************************************************************
func getUploadedFileSet() {
let documentsURL = URL(string: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let appURL = documentsURL?.appendingPathComponent(APP_DISTINGUISHED_NAME)
let jsonFileURL = appURL?.appendingPathComponent(UPLOADED_ITEMS_DB_JSON)
if FileManager.default.fileExists(atPath: (jsonFileURL?.absoluteString)!) {
do {
let data = try Data(contentsOf: jsonFileURL!, options: .alwaysMapped)
let json = JSON(data: data)
if json != nil {
for (key, subJson) in json[kCollaborations] {
let stringArray:[String] = subJson.arrayValue.map { $0.string! }
let stringSet = Set(stringArray)
collaborationDictionary.updateValue(stringSet, forKey: key)
}
} else {
print("Could not get json from file, make sure that file contains valid json.")
}
} catch let error {
print(error.localizedDescription)
}
}
}
// **************************************************************************
func saveUploadedFilesSet() {
let documentsURL = URL(string: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let appURL = documentsURL?.appendingPathComponent(APP_DISTINGUISHED_NAME)
let jsonFileURL = appURL?.appendingPathComponent(UPLOADED_ITEMS_DB_JSON)
let adjustedJSONFileURL = URL(fileURLWithPath:(jsonFileURL?.absoluteString)!)
do {
let dirExists = FileManager.default.fileExists(atPath: (appURL?.absoluteString)!)
if !dirExists {
try FileManager.default.createDirectory(atPath: (appURL?.absoluteString)!, withIntermediateDirectories: false, attributes: nil)
}
// Convert set elements to arrays
var convertedCollaborationDictionary: [String:[String]] = [:]
for (sessionID, fileNameSet) in collaborationDictionary {
let array = Array(fileNameSet)
convertedCollaborationDictionary.updateValue(array, forKey: sessionID)
}
let json: JSON = JSON(convertedCollaborationDictionary)
let fullJSON: JSON = [kCollaborations:json.object]
let data = try fullJSON.rawData()
try data.write(to: adjustedJSONFileURL, options: .atomic)
} catch let error as NSError {
print(error.localizedDescription);
}
}
If you dig into the source, SwiftyJSON wraps JSONSerialization, which can both be initialized and converted back to Data which is knows how to read and write itself from disk:
func readJSON() -> JSON? {
guard let url = Bundle.main.url(forResource: "data", withExtension: "json"),
let data = try? Data(contentsOf: url) else {
return nil
}
return JSON(data: data)
}
func write(json: JSON, to url: URL) throws {
let data = try json.rawData()
try data.write(to: url)
}
Note that you can load your static data from anywhere including your Bundle, but you can only write to the sandbox (ie the Documents directory). You may wish to copy from your Bundle to the documents directory on first run if you are planning on reading/writing to the same file.
Also your sample JSON is bad (lint it). You need a comma after "Photo_0.jpeg"]
I am playing around with Apple's new Swift programming language and have some problems...
Currently I'm trying to read a plist file, in Objective-C I would do the following to get the content as a NSDictionary:
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"Config" ofType:#"plist"];
NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:filePath];
How do I get a plist as a Dictionary in Swift?
I assume I can get the path to the plist with:
let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist")
When this works (If it's correct?): How do I get the content as a Dictionary?
Also a more general question:
Is it OK to use the default NS* classes? I think so...or am I missing something? As far as I know the default framework NS* classes are still valid and alright to use?
You can still use NSDictionaries in Swift:
For Swift 4
var nsDictionary: NSDictionary?
if let path = Bundle.main.path(forResource: "Config", ofType: "plist") {
nsDictionary = NSDictionary(contentsOfFile: path)
}
For Swift 3+
if let path = Bundle.main.path(forResource: "Config", ofType: "plist"),
let myDict = NSDictionary(contentsOfFile: path){
// Use your myDict here
}
And older versions of Swift
var myDict: NSDictionary?
if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist") {
myDict = NSDictionary(contentsOfFile: path)
}
if let dict = myDict {
// Use your dict here
}
The NSClasses are still available and perfectly fine to use in Swift. I think they'll probably want to shift focus to swift soon, but currently the swift APIs don't have all the functionality of the core NSClasses.
This is what I do if I want to convert a .plist to a Swift dictionary:
if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist") {
if let dict = NSDictionary(contentsOfFile: path) as? Dictionary<String, AnyObject> {
// use swift dictionary as normal
}
}
Edited for Swift 2.0:
if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist"), dict = NSDictionary(contentsOfFile: path) as? [String: AnyObject] {
// use swift dictionary as normal
}
Edited for Swift 3.0:
if let path = Bundle.main.path(forResource: "Config", ofType: "plist"), let dict = NSDictionary(contentsOfFile: path) as? [String: AnyObject] {
// use swift dictionary as normal
}
Swift 4.0
You can now use the Decodable protocol to Decode a .plist into a custom struct. I will go over a basic example, for more complicated .plist structures I recommend reading up on Decodable/Encodable (a good resource is here: https://benscheirman.com/2017/06/swift-json/).
First setup your struct into the format of your .plist file. For this example I will consider a .plist with a root level Dictionary and 3 entries: 1 String with key "name", 1 Int with key "age", and 1 Boolean with key "single". Here is the struct:
struct Config: Decodable {
private enum CodingKeys: String, CodingKey {
case name, age, single
}
let name: String
let age: Int
let single: Bool
}
Simple enough. Now the cool part. Using the PropertyListDecoder class we can easily parse the .plist file into an instantiation of this struct:
func parseConfig() -> Config {
let url = Bundle.main.url(forResource: "Config", withExtension: "plist")!
let data = try! Data(contentsOf: url)
let decoder = PropertyListDecoder()
return try! decoder.decode(Config.self, from: data)
}
Not much more code to worry about, and its all in Swift. Better yet we now have an instantiation of the Config struct that we can easily use:
let config = parseConfig()
print(config.name)
print(config.age)
print(config.single)
This Prints the value for the "name", "age", and "single" keys in the .plist.
In swift 3.0 Reading from Plist.
func readPropertyList() {
var propertyListFormat = PropertyListSerialization.PropertyListFormat.xml //Format of the Property List.
var plistData: [String: AnyObject] = [:] //Our data
let plistPath: String? = Bundle.main.path(forResource: "data", ofType: "plist")! //the path of the data
let plistXML = FileManager.default.contents(atPath: plistPath!)!
do {//convert the data to a dictionary and handle errors.
plistData = try PropertyListSerialization.propertyList(from: plistXML, options: .mutableContainersAndLeaves, format: &propertyListFormat) as! [String:AnyObject]
} catch {
print("Error reading plist: \(error), format: \(propertyListFormat)")
}
}
Read More
HOW TO USE PROPERTY LISTS (.PLIST) IN SWIFT.
This answer uses Swift native objects rather than NSDictionary.
Swift 3.0
//get the path of the plist file
guard let plistPath = Bundle.main.path(forResource: "level1", ofType: "plist") else { return }
//load the plist as data in memory
guard let plistData = FileManager.default.contents(atPath: plistPath) else { return }
//use the format of a property list (xml)
var format = PropertyListSerialization.PropertyListFormat.xml
//convert the plist data to a Swift Dictionary
guard let plistDict = try! PropertyListSerialization.propertyList(from: plistData, options: .mutableContainersAndLeaves, format: &format) as? [String : AnyObject] else { return }
//access the values in the dictionary
if let value = plistDict["aKey"] as? String {
//do something with your value
print(value)
}
//you can also use the coalesce operator to handle possible nil values
var myValue = plistDict["aKey"] ?? ""
I have been working with Swift 3.0 and wanted to contribute an answer for the updated syntax. Additionally, and possibly more importantly, I am using the PropertyListSerialization object to do the heavy lifting, which is a lot more flexible than just using the NSDictionary as it allows for an Array as the root type of the plist.
Below is a screenshot of the plist I am using. It is a little complicated, so as to show the power available, but this will work for any allowable combination of plist types.
As you can see I am using an Array of String:String dictionaries to store a list of website names and their corresponding URL.
I am using the PropertyListSerialization object, as mentioned above, to do the heavy lifting for me. Additionally, Swift 3.0 has become more "Swifty" so all of the object names have lost the "NS" prefix.
let path = Bundle.main().pathForResource("DefaultSiteList", ofType: "plist")!
let url = URL(fileURLWithPath: path)
let data = try! Data(contentsOf: url)
let plist = try! PropertyListSerialization.propertyList(from: data, options: .mutableContainers, format: nil)
After the above code runs plist will be of type Array<AnyObject>, but we know what type it really is so we can cast it to the correct type:
let dictArray = plist as! [[String:String]]
// [[String:String]] is equivalent to Array< Dictionary<String, String> >
And now we can access the various properties of our Array of String:String Dictionaries in a natural way. Hopefully to convert them into actual strongly typed structs or classes ;)
print(dictArray[0]["Name"])
Swift 5
If you want to fetch specific value for some key then we can use below extension which uses infoDictionary property on Bundle.
Bundle.main.infoDictionary can be used to get all info.plist values in the form dictionary and so we can directly query using object(forInfoDictionaryKey: key) method on Bundle
extension Bundle {
static func infoPlistValue(forKey key: String) -> Any? {
guard let value = Bundle.main.object(forInfoDictionaryKey: key) else {
return nil
}
return value
}
}
Usage
guard let apiURL = Bundle.infoPlistValue(forKey: "API_URL_KEY") as? String else { return }
It is best to use native dictionaries and arrays because they have been optimized for use with swift. That being said you can use NS... classes in swift and I think this situation warrants that. Here is how you would implement it:
var path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist")
var dict = NSDictionary(contentsOfFile: path)
So far (in my opinion) this is the easiest and most efficient way to access a plist, but in the future I expect that apple will add more functionality (such as using plist) into native dictionaries.
Swift - Read/Write plist and text file....
override func viewDidLoad() {
super.viewDidLoad()
let fileManager = (NSFileManager .defaultManager())
let directorys : [String]? = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory,NSSearchPathDomainMask.AllDomainsMask, true) as? [String]
if (directorys != nil){
let directories:[String] = directorys!;
let dictionary = directories[0]; //documents directory
// Create and insert the data into the Plist file ....
let plistfile = "myPlist.plist"
var myDictionary: NSMutableDictionary = ["Content": "This is a sample Plist file ........."]
let plistpath = dictionary.stringByAppendingPathComponent(plistfile);
if !fileManager .fileExistsAtPath(plistpath){//writing Plist file
myDictionary.writeToFile(plistpath, atomically: false)
}
else{ //Reading Plist file
println("Plist file found")
let resultDictionary = NSMutableDictionary(contentsOfFile: plistpath)
println(resultDictionary?.description)
}
// Create and insert the data into the Text file ....
let textfile = "myText.txt"
let sampleText = "This is a sample text file ......... "
let textpath = dictionary.stringByAppendingPathComponent(textfile);
if !fileManager .fileExistsAtPath(textpath){//writing text file
sampleText.writeToFile(textpath, atomically: false, encoding: NSUTF8StringEncoding, error: nil);
} else{
//Reading text file
let reulttext = String(contentsOfFile: textpath, encoding: NSUTF8StringEncoding, error: nil)
println(reulttext)
}
}
else {
println("directory is empty")
}
}
Swift 2.0 : Accessing Info.Plist
I have a Dictionary named CoachMarksDictionary with a boolean value in Info.Plist . I want to access the bool value and make it true.
let path = NSBundle.mainBundle().pathForResource("Info", ofType: "plist")!
let dict = NSDictionary(contentsOfFile: path) as! [String: AnyObject]
if let CoachMarksDict = dict["CoachMarksDictionary"] {
print("Info.plist : \(CoachMarksDict)")
var dashC = CoachMarksDict["DashBoardCompleted"] as! Bool
print("DashBoardCompleted state :\(dashC) ")
}
Writing To Plist:
From a Custom Plist:-
(Make from File-New-File-Resource-PropertyList. Added three strings named : DashBoard_New, DashBoard_Draft, DashBoard_Completed)
func writeToCoachMarksPlist(status:String?,keyName:String?)
{
let path1 = NSBundle.mainBundle().pathForResource("CoachMarks", ofType: "plist")
let coachMarksDICT = NSMutableDictionary(contentsOfFile: path1!)! as NSMutableDictionary
var coachMarksMine = coachMarksDICT.objectForKey(keyName!)
coachMarksMine = status
coachMarksDICT.setValue(status, forKey: keyName!)
coachMarksDICT.writeToFile(path1!, atomically: true)
}
The method can be called as
self.writeToCoachMarksPlist(" true - means user has checked the marks",keyName: "the key in the CoachMarks dictionary").
Converted into a convenience extension via Nick's answer:
extension Dictionary {
static func contentsOf(path: URL) -> Dictionary<String, AnyObject> {
let data = try! Data(contentsOf: path)
let plist = try! PropertyListSerialization.propertyList(from: data, options: .mutableContainers, format: nil)
return plist as! [String: AnyObject]
}
}
usage:
let path = Bundle.main.path(forResource: "plistName", ofType: "plist")!
let url = URL(fileURLWithPath: path)
let dict = Dictionary<String, AnyObject>.contentsOf(path: url)
I'd be willing to bet that it would also work to create a similar extension for Arrays
Since this answer isn't here yet, just wanted to point out you can also use the infoDictionary property to get the info plist as a dictionary, Bundle.main.infoDictionary.
Although something like Bundle.main.object(forInfoDictionaryKey: kCFBundleNameKey as String) may be faster if you're only interested in a specific item in the info plist.
// Swift 4
// Getting info plist as a dictionary
let dictionary = Bundle.main.infoDictionary
// Getting the app display name from the info plist
Bundle.main.infoDictionary?[kCFBundleNameKey as String]
// Getting the app display name from the info plist (another way)
Bundle.main.object(forInfoDictionaryKey: kCFBundleNameKey as String)
can actually do it in 1 line
var dict = NSDictionary(contentsOfFile: NSBundle.mainBundle().pathForResource("Config", ofType: "plist"))
You can read plist in SWIFT Language in this way:
let path = NSBundle.mainBundle().pathForResource("PriceList", ofType: "plist")
let dict = NSDictionary(contentsOfFile: path)
Read Single Dictionary value:
let test: AnyObject = dict.objectForKey("index1")
If you want to get full multi-dimensional dictionary in plist:
let value: AnyObject = dict.objectForKey("index2").objectForKey("date")
Here is the plist:
<plist version="1.0">
<dict>
<key>index2</key>
<dict>
<key>date</key>
<string>20140610</string>
<key>amount</key>
<string>110</string>
</dict>
<key>index1</key>
<dict>
<key>amount</key>
<string>125</string>
<key>date</key>
<string>20140212</string>
</dict>
</dict>
</plist>
in my case I create a NSDictionary called appSettings and add all needed keys. For this case, the solution is:
if let dict = NSBundle.mainBundle().objectForInfoDictionaryKey("appSettings") {
if let configAppToken = dict["myKeyInsideAppSettings"] as? String {
}
}
Step 1 : Simple and fastest way to parse plist in swift 3+
extension Bundle {
func parsePlist(ofName name: String) -> [String: AnyObject]? {
// check if plist data available
guard let plistURL = Bundle.main.url(forResource: name, withExtension: "plist"),
let data = try? Data(contentsOf: plistURL)
else {
return nil
}
// parse plist into [String: Anyobject]
guard let plistDictionary = try? PropertyListSerialization.propertyList(from: data, options: [], format: nil) as? [String: AnyObject] else {
return nil
}
return plistDictionary
}
}
Step 2: How to use:
Bundle().parsePlist(ofName: "Your-Plist-Name")
You can use that, I create a simple extension for Dictionary in github https://github.com/DaRkD0G/LoadExtension
extension Dictionary {
/**
Load a Plist file from the app bundle into a new dictionary
:param: File name
:return: Dictionary<String, AnyObject>?
*/
static func loadPlistFromProject(filename: String) -> Dictionary<String, AnyObject>? {
if let path = NSBundle.mainBundle().pathForResource("GameParam", ofType: "plist") {
return NSDictionary(contentsOfFile: path) as? Dictionary<String, AnyObject>
}
println("Could not find file: \(filename)")
return nil
}
}
And you can use that for load
/**
Example function for load Files Plist
:param: Name File Plist
*/
func loadPlist(filename: String) -> ExampleClass? {
if let dictionary = Dictionary<String, AnyObject>.loadPlistFromProject(filename) {
let stringValue = (dictionary["name"] as NSString)
let intergerValue = (dictionary["score"] as NSString).integerValue
let doubleValue = (dictionary["transition"] as NSString).doubleValue
return ExampleClass(stringValue: stringValue, intergerValue: intergerValue, doubleValue: doubleValue)
}
return nil
}
Here is a bit shorter version, based on #connor 's answer
guard let path = Bundle.main.path(forResource: "GoogleService-Info", ofType: "plist"),
let myDict = NSDictionary(contentsOfFile: path) else {
return nil
}
let value = dict.value(forKey: "CLIENT_ID") as! String?
Swift 3.0
if let path = Bundle.main.path(forResource: "config", ofType: "plist") {
let dict = NSDictionary(contentsOfFile: path)
// use dictionary
}
The easiest way to do this in my opinion.
I've created a simple Dictionary initializer that replaces NSDictionary(contentsOfFile: path). Just remove the NS.
extension Dictionary where Key == String, Value == Any {
public init?(contentsOfFile path: String) {
let url = URL(fileURLWithPath: path)
self.init(contentsOfURL: url)
}
public init?(contentsOfURL url: URL) {
guard let data = try? Data(contentsOf: url),
let dictionary = (try? PropertyListSerialization.propertyList(from: data, options: [], format: nil) as? [String: Any]) ?? nil
else { return nil }
self = dictionary
}
}
You can use it like so:
let filePath = Bundle.main.path(forResource: "Preferences", ofType: "plist")!
let preferences = Dictionary(contentsOfFile: filePath)!
UserDefaults.standard.register(defaults: preferences)
Swift 4.0 iOS 11.2.6 list parsed and code to parse it, based on https://stackoverflow.com/users/3647770/ashok-r answer above.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<array>
<dict>
<key>identity</key>
<string>blah-1</string>
<key>major</key>
<string>1</string>
<key>minor</key>
<string>1</string>
<key>uuid</key>
<string>f45321</string>
<key>web</key>
<string>http://web</string>
</dict>
<dict>
<key>identity</key>
<string></string>
<key>major</key>
<string></string>
<key>minor</key>
<string></string>
<key>uuid</key>
<string></string>
<key>web</key>
<string></string>
</dict>
</array>
</plist>
do {
let plistXML = try Data(contentsOf: url)
var plistData: [[String: AnyObject]] = [[:]]
var propertyListFormat = PropertyListSerialization.PropertyListFormat.xml
do {
plistData = try PropertyListSerialization.propertyList(from: plistXML, options: .mutableContainersAndLeaves, format: &propertyListFormat) as! [[String:AnyObject]]
} catch {
print("Error reading plist: \(error), format: \(propertyListFormat)")
}
} catch {
print("error no upload")
}
Here's the solution I found:
let levelBlocks = NSDictionary(contentsOfFile: NSBundle.mainBundle().pathForResource("LevelBlocks", ofType: "plist"))
let test: AnyObject = levelBlocks.objectForKey("Level1")
println(test) // Prints the value of test
I set the type of test to AnyObject to silence a warning about an unexpected inference that could occur.
Also, it has to be done in a class method.
To access and save a specific value of a known type:
let value = levelBlocks.objectForKey("Level1").objectForKey("amount") as Int
println(toString(value)) // Converts value to String and prints it
I use swift dictionaries but convert them to and from NSDictionaries in my file manager class like so:
func writePlist(fileName:String, myDict:Dictionary<String, AnyObject>){
let docsDir:String = dirPaths[0] as String
let docPath = docsDir + "/" + fileName
let thisDict = myDict as NSDictionary
if(thisDict.writeToFile(docPath, atomically: true)){
NSLog("success")
} else {
NSLog("failure")
}
}
func getPlist(fileName:String)->Dictionary<String, AnyObject>{
let docsDir:String = dirPaths[0] as String
let docPath = docsDir + "/" + fileName
let thisDict = NSDictionary(contentsOfFile: docPath)
return thisDict! as! Dictionary<String, AnyObject>
}
This seems the least troubling way to read and write but let's the rest of my code stay as swift as possible.
Plist is a simple Swift enum I made for working with property lists.
// load an applications info.plist data
let info = Plist(NSBundle.mainBundle().infoDictionary)
let identifier = info["CFBundleIndentifier"].string!
More examples:
import Plist
// initialize using an NSDictionary
// and retrieve keyed values
let info = Plist(dict)
let name = info["name"].string ?? ""
let age = info["age"].int ?? 0
// initialize using an NSArray
// and retrieve indexed values
let info = Plist(array)
let itemAtIndex0 = info[0].value
// utility initiaizer to load a plist file at specified path
let info = Plist(path: "path_to_plist_file")
// we support index chaining - you can get to a dictionary from an array via
// a dictionary and so on
// don't worry, the following will not fail with errors in case
// the index path is invalid
if let complicatedAccessOfSomeStringValueOfInterest = info["dictKey"][10]["anotherKey"].string {
// do something
}
else {
// data cannot be indexed
}
// you can also re-use parts of a plist data structure
let info = Plist(...)
let firstSection = info["Sections"][0]["SectionData"]
let sectionKey = firstSection["key"].string!
let sectionSecret = firstSection["secret"].int!
Plist.swift
Plist itself is quite simple, here's its listing in case you to refer directly.
//
// Plist.swift
//
import Foundation
public enum Plist {
case dictionary(NSDictionary)
case Array(NSArray)
case Value(Any)
case none
public init(_ dict: NSDictionary) {
self = .dictionary(dict)
}
public init(_ array: NSArray) {
self = .Array(array)
}
public init(_ value: Any?) {
self = Plist.wrap(value)
}
}
// MARK:- initialize from a path
extension Plist {
public init(path: String) {
if let dict = NSDictionary(contentsOfFile: path) {
self = .dictionary(dict)
}
else if let array = NSArray(contentsOfFile: path) {
self = .Array(array)
}
else {
self = .none
}
}
}
// MARK:- private helpers
extension Plist {
/// wraps a given object to a Plist
fileprivate static func wrap(_ object: Any?) -> Plist {
if let dict = object as? NSDictionary {
return .dictionary(dict)
}
if let array = object as? NSArray {
return .Array(array)
}
if let value = object {
return .Value(value)
}
return .none
}
/// tries to cast to an optional T
fileprivate func cast<T>() -> T? {
switch self {
case let .Value(value):
return value as? T
default:
return nil
}
}
}
// MARK:- subscripting
extension Plist {
/// index a dictionary
public subscript(key: String) -> Plist {
switch self {
case let .dictionary(dict):
let v = dict.object(forKey: key)
return Plist.wrap(v)
default:
return .none
}
}
/// index an array
public subscript(index: Int) -> Plist {
switch self {
case let .Array(array):
if index >= 0 && index < array.count {
return Plist.wrap(array[index])
}
return .none
default:
return .none
}
}
}
// MARK:- Value extraction
extension Plist {
public var string: String? { return cast() }
public var int: Int? { return cast() }
public var double: Double? { return cast() }
public var float: Float? { return cast() }
public var date: Date? { return cast() }
public var data: Data? { return cast() }
public var number: NSNumber? { return cast() }
public var bool: Bool? { return cast() }
// unwraps and returns the underlying value
public var value: Any? {
switch self {
case let .Value(value):
return value
case let .dictionary(dict):
return dict
case let .Array(array):
return array
case .none:
return nil
}
}
// returns the underlying array
public var array: NSArray? {
switch self {
case let .Array(array):
return array
default:
return nil
}
}
// returns the underlying dictionary
public var dict: NSDictionary? {
switch self {
case let .dictionary(dict):
return dict
default:
return nil
}
}
}
// MARK:- CustomStringConvertible
extension Plist : CustomStringConvertible {
public var description:String {
switch self {
case let .Array(array): return "(array \(array))"
case let .dictionary(dict): return "(dict \(dict))"
case let .Value(value): return "(value \(value))"
case .none: return "(none)"
}
}
}
Swift 3.0
if you want to read a "2-dimensional Array" from .plist, you can try it like this:
if let path = Bundle.main.path(forResource: "Info", ofType: "plist") {
if let dimension1 = NSDictionary(contentsOfFile: path) {
if let dimension2 = dimension1["key"] as? [String] {
destination_array = dimension2
}
}
}
If you have Info.plist, then use
Bundle.main.infoDictionary
Simple struct to access plist file (Swift 2.0)
struct Configuration {
static let path = NSBundle.mainBundle().pathForResource("Info", ofType: "plist")!
static let dict = NSDictionary(contentsOfFile: path) as! [String: AnyObject]
static let someValue = dict["someKey"] as! String
}
Usage:
print("someValue = \(Configuration.someValue)")