Facing issue while unarchivedObject data - ios

Question

I have created a generic function for NSKeyedArchiver and NSKeyedUnarchiver. I am able to archive the array data but while doing unarchive facing an issue. Below is my code:
NSKeyedArchiver code:
func cacheData<T>(data: T) {
do {
let codedData = try NSKeyedArchiver.archivedData(withRootObject: data, requiringSecureCoding: false)
} catch {
print("Exception while caching data \(error)")
}
}
NSKeyedUnarchiver code:
func getCacheData<T>(encodedData: Data, ofClass: T.Type) -> [T]? {
do{
if let decodedData = try NSKeyedUnarchiver.unarchivedObject(ofClasses: [NSArray.self, T.self as! AnyClass], from: encodedData){
return decodedData as? [T]
}
} catch {
print("Exception while decode array cache data \(error)")
}
return nil
}
Above code works fine for having only strings, integers variables but it failed if having custom classes variables. How to allow these custom classes in NSKeyedUnarchiver.
I am getting below error:
Exception while decode array cache data Error
Domain=NSCocoaErrorDomain Code=4864 "value for key 'customclass1' was of
unexpected class 'CustomClass1'. Allowed classes are '{(
NSArray,
MainClass )}'." UserInfo={NSDebugDescription=value for key 'customclass2' was of unexpected class 'CustomClass2'. Allowed classes are
'{(
NSArray,
MainClass )}'.}
Any idea how to solve this?

Answer 1

Make sure all your class are confirming to NSCoding. Something like this:
func archiveAndUnarchive() {
let class2 = Class2(value: "Value")
let class1 = Class1(name: "Name", class2: class2)
do {
// ARCHIVING
let data = try NSKeyedArchiver.archivedData(withRootObject: class1, requiringSecureCoding: false)
// UNARCHIVING
if let decodedData = try NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(data) as? Class1 {
print(decodedData)
}
} catch {
print(error)
}
}
class Class1: NSObject, NSCoding {
var name: String?
var class2: Class2?
func encode(with coder: NSCoder) {
coder.encode(name, forKey: "name")
coder.encode(class2, forKey: "class2")
}
required init?(coder: NSCoder) {
super.init()
self.name = coder.decodeObject(forKey: "name") as? String ?? ""
self.class2 = coder.decodeObject(forKey: "class2") as? Class2
}
init(name: String, class2: Class2) {
super.init()
self.name = name
self.class2 = class2
}
}
class Class2: NSObject, NSCoding {
var value: String?
func encode(with coder: NSCoder) {
coder.encode(value, forKey: "value")
}
required init?(coder: NSCoder) {
super.init()
self.value = coder.decodeObject(forKey: "value") as? String
}
init(value: String) {
super.init()
self.value = value
}
}