我在NSUserDefaults中保存颜色有一个小问题。在objective-c很容易:
-(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];
}
上面的代码在objective-c中工作正常,但是当我尝试在swift中编写相同的代码时,我在从NSUserDefaults读取颜色时收到错误。
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
}
谢谢,对不起我的英文!
对于Objective C
像这样的地方。
NSData *colorData = [NSKeyedArchiver archivedDataWithRootObject:color];
[[NSUserDefaults standardUserDefaults] setObject:colorData forKey:@"myColor"];
要像这样回来。
NSData *colorData = [[NSUserDefaults standardUserDefaults] objectForKey:@"myColor"];
UIColor *color = [NSKeyedUnarchiver unarchiveObjectWithData:colorData];
对于斯威夫特
像这样设置
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")
}
得到这样的。
if let userSelectedColorData = NSUserDefaults.standardUserDefaults().objectForKey("UserSelectedColor") as? NSData {
if let userSelectedColor = NSKeyedUnarchiver.unarchiveObjectWithData(userSelectedColorData) as? UIColor {
println(userSelectedColor)
}
}
对于Swift 4.2
像这样的地方。
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")
要像这样回来。
if let userSelectedColorData = UserDefaults.standard.object(forKey: "UserSelectedColor") as? Data {
if let userSelectedColor = NSKeyedUnarchiver.unarchiveObject(with:userSelectedColorData as Data) as? UIColor {
print(userSelectedColor)
}
}
在用户默认值中存储NSColor实例
将用户默认值中的值存储在aColor中作为键aKey的值
NSData * theData = [NSArchiver archivedDataWithRootObject:aColor]; [[NSUserDefaults standardUserDefaults] setObject:theData forKey:aKey];