I have a litle problem with saving a color in NSUserDefaults . In objective-c is easy :
-(NSColor *)colorForKey:(NSString *)key{
NSData *data;
NSColor *color;
data = [[NSUserDefaults standardUserDefaults] objectForKey:key];
color= [NSUnarchiver unarchiveObjectWithData:data];
if( ! [color isKindOfClass:[NSColor class]] ){
color = nil;
}
return color;
}
-(void)setColor:(NSColor *)color forKey:(NSString *)key{
NSData *data = [NSArchiver archivedDataWithRootObject:color];
[[NSUserDefaults standardUserDefaults] setObject:data forKey:key];
}
The above code works fine in objective-c, but when i try to write same code in swift, I receive errors at reading color from NSUserDefaults.
func saveColorForKey (color:NSColor , key:NSString ) {
var data:NSData = NSData()
data = NSArchiver.archivedDataWithRootObject(color)
NSUserDefaults.standardUserDefaults().setObject(data, forKey: key)
}
func colorForKey(key:NSString) -> NSColor{
var data: AnyObject? = NSUserDefaults.standardUserDefaults().objectForKey(key)
var color: AnyObject? = NSUnarchiver.unarchiveObjectWithData(data? as NSData)
return color as NSColor
}
Thanks , and sorry for my english !
The easiest way would be using NSUserDefaults . In this case you are storing the string "Coding Explorer" and you can reference by the key "userNameKey" .
It appears the limit is the maximum file size for iOS (logically), which is currently 4GB: https://discussions.apple.com/thread/1763096?tstart=0. The precise size of the data is circumscribed by the compiler types (NSData, NSString, etc.) or the files in your asset bundle.
Saving to NSUserDefaults : Basically, all you have to do is load NSUserDefaults, and then tell it to save a value to a specific key. Here is a simple example of writing an integer to NSUserDefaults: NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
Overview. The NSUserDefaults class provides a programmatic interface for interacting with the defaults system. The defaults system allows an app to customize its behavior to match a user's preferences. For example, you can allow users to specify their preferred units of measurement or media playback speed.
For Objective C
place like this.
NSData *colorData = [NSKeyedArchiver archivedDataWithRootObject:color];
[[NSUserDefaults standardUserDefaults] setObject:colorData forKey:@"myColor"];
To get back like this.
NSData *colorData = [[NSUserDefaults standardUserDefaults] objectForKey:@"myColor"];
UIColor *color = [NSKeyedUnarchiver unarchiveObjectWithData:colorData];
For Swift
set like this
var userSelectedColor : NSData? = (NSUserDefaults.standardUserDefaults().objectForKey("UserSelectedColor") as? NSData)
if (userSelectedColor != nil) {
var colorToSetAsDefault : UIColor = UIColor.redColor()
var data : NSData = NSKeyedArchiver.archivedDataWithRootObject(colorToSetAsDefault)
NSUserDefaults.standardUserDefaults().setObject(data, forKey: "UserSelectedColor")
NSUserDefaults.standardUserDefaults().synchronize()
println("SET DEFAULT USER COLOR TO RED")
}
get like this.
if let userSelectedColorData = NSUserDefaults.standardUserDefaults().objectForKey("UserSelectedColor") as? NSData {
if let userSelectedColor = NSKeyedUnarchiver.unarchiveObjectWithData(userSelectedColorData) as? UIColor {
println(userSelectedColor)
}
}
For Swift 4.2
place like this.
let colorToSetAsDefault : UIColor = UIColor.red
let data : Data = NSKeyedArchiver.archivedData(withRootObject: colorToSetAsDefault) as Data
UserDefaults.standard.set(data, forKey: "UserSelectedColor")
UserDefaults.standard.synchronize()
print("SET DEFAULT USER COLOR TO RED")
To get back like this.
if let userSelectedColorData = UserDefaults.standard.object(forKey: "UserSelectedColor") as? Data {
if let userSelectedColor = NSKeyedUnarchiver.unarchiveObject(with:userSelectedColorData as Data) as? UIColor {
print(userSelectedColor)
}
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With