objective c - Why my NSColor class NSConcreteData? -

In the data model I have defined color as variable attribute and for this it has specified ColorTransformer it works, With the help of a single transformer, I can bind it with ColorPicker, save the document and open it. But when I try to get it from code:

  escocolor * color = corner Colour; NSLog (@ "corner color =% @ \ n% @", color, color class);  

I have found the purpose of NSMutableConcreteData:

  bezierMesh [22,164: 730,708] corner color = & lt; 040b7374 7265616d 74,797,065 6481e803 84,014,084 8484074e 53436f6c 6f720084 84084e53 4f626a65 63740085 84016301 84046666 66660183 6eb7613d 8357703e 3e8352b8 1e3f86 & gt; NSConcreteMutableData   
 Amendments getter and does not help them setter:  
  - (NSColor *) color {[self willAccessValueForKey: @ "color" ]; NSDT * color data = [self-esteemed: @ "color"]; [Self-made AccessValueForKey: @ "color"]; If (colorata == zero) {return zero; } Enkolar * Color = [NSKAdNeCeCeCeCejectedAdvancedToddataDataDataData]; The color of the return; } - (zero) set collar: (nscillor *) color {nslog (@ "--------------> color set% @", color); NSDTA * The Data = [stored on NSACriteDataAbject: Color]; [Will Will Changewolegore: @ "Color"]; [Auto setprimitative value: datatai for: @ "color"]; [Self-made variables: @ "color"]; }  
 
 This causes an error: 
 
  [NSKeyedUnarchiver initForReadingWithData:]: can not be decoded by non-stop collection NSKeyedUnarchiver  
 
 How to get the color NSColor? 
 

Here's a NSString & lt; -> NSColor I wrote a few times ago, which is designed to store colors using RGB values ​​within NSUserDefaults because I have the default using NSData did not like objects:

StringColourTransformer.h:

  @interface StringColourTransformer: NSValueTransformer + (NSString *) toString: (NSColor *) value; + (NSColor *) String: (NSString *) value; @end  

StringColourTransformer.m:

  #import "StringColourTransformer.h" @implementation StringColourTransformer + (NSString *) toString: (NSColor *) value { StringColor Transformers * Transformer = [[String Collar Transformer Alok] init]; NSString * str = [Transformer reverse transcript value: value]; Return str; } + (NSColor *) String: (NSString *) value {StringColourTransformer * Transformer = [[String Collar Transformer Alok] init]; NSColor * color = (NSColor *) [Transformer changed value: value]; The color of the return; } + (Class) changed value class {returns [enclosure class]; } + (BOOL) allowrevers Transformation {return yes; } - Value converted (id): (id) value {CGFloat r = 0.0, g = 0.0, b = 0.0, a = 1.0; // Only NSString classes are reverse-transworn if ([valueKindOfClass: [NSString class]]) {NSString * stringValue = (NSString *) value; sscanf ([stringValue UTF8String], #ifdef __x86_64 "% lf% lf% lf% lf", #else "% f% f% f% f", #endif & amp; r, & amp; G, and B & Amp; A); } Returns [Encooler color with-silicated red: R green: g blue: B alpha: A]; } - (ID) Reverse Transformed Value: (ID) Value {CGFloat r = 0.0, g = 0.0, b = 0.0, a = 1.0; // Only nssolar squares are converted if ([value iskindoff class: [enclosure class]]) {enocholar * color value = (nscillor *) value; Nscillore * converted = [colored colored coloring pattern spacingname: @ "nscilbrated rgbcularspace"]; [Converted Red: And R Green: And G Blue: & amp; B alpha: & amp; a;); } Return [NSString stringWithFormat: @ "% 3.f% .3f% .3f% .3f", r, g, b, a]; } @end  

As you can see I have provided some class methods to make it easier using the code ( toString and FromString ).

It should be registered early in the life cycle of the app so that its use can be used to change the values ​​within the IB (this is called a singleton where _stringColourTransformer is example Variable):

  _stringColourTransformer = [[string collar transformer light] init]; [NSValueTransformer setValueTransformer: _stringColourTransformer forName: @ "StringColor Transformer"];  

And the conversion is as simple:

  NSColor * color = [StringColourTransformer fromString: @ "1.0 1.0 0.0 1.0"];   
 Note: By looking at the code I can now probably use  [NSValueTranformer valueTransformerForName:]  in  toString  /  string  Instead of making a new instance every time, it is probably less expensive.