How to load a UIColor from a Plist

Regarding saving the UIColor in a Plist: I have trie开发者_如何学Pythond different ways but not been able to do so, I want to save and retrieve the color values in a plist file.

I can not extract the data value of the color using nslog and save it in the plist.

Is there any other way to do so?

I prefer using string to store the color. The parsing code that does this shown below (cut out from https://github.com/xslim/TKThemeManager/blob/master/TKThemeManager.m#L162)

+ (UIColor *)colorFromString:(NSString *)hexString {    
    NSScanner *scanner = [NSScanner scannerWithString:hexString];
    unsigned hex;
    BOOL success = [scanner scanHexInt:&hex];

    if (!success) return nil;
    if ([hexString length] <= 6) {
        return UIColorFromRGB(hex);
    } else {
        unsigned color = (hex & 0xFFFFFF00) >> 8;
        CGFloat alpha = 1.0 * (hex & 0xFF) / 255.0;
        return UIColorFromRGBA(color, alpha);
    }
}

For a quick solution (but maybe not the most pretty one):

• Add the color property as a type Number into the plist
• Enter the color as an RGB-hexdecimal, for example: 0xff00e3
• Read it out and process it with a macro like below

Here is a code example:

// Add this code to some include, for reuse
#define UIColorFromRGBA(rgbValue, alphaValue) ([UIColor colorWithRed:((CGFloat)((rgbValue & 0xFF0000) >> 16)) / 255.0 \
                                                               green:((CGFloat)((rgbValue & 0xFF00) >> 8)) / 255.0 \
                                                                blue:((CGFloat)(rgbValue & 0xFF)) / 255.0 \
                                                               alpha:alphaValue])

// This goes into your controller / view
NSDictionary *myPropertiesDict = [NSDictionary dictionaryWithContentsOfFile:...];
UIColor *titleColor = UIColorFromRGBA([myPropertiesDict[@"titleColor"] integerValue], 1.0);

After entering the color as hexdecimal, the plist editor will show it as a decimal number. Not nice. As a developer you normally copy paste the colors from a design document anyway, so the need to read the color values is not that big.

I did a category for this:

@implementation UIColor (EPPZRepresenter)


NSString *NSStringFromUIColor(UIColor *color)
{
    const CGFloat *components = CGColorGetComponents(color.CGColor);
    return [NSString stringWithFormat:@"[%f, %f, %f, %f]",
            components[0],
            components[1],
            components[2],
            components[3]];
}

UIColor *UIColorFromNSString(NSString *string)
{
    NSString *componentsString = [[string stringByReplacingOccurrencesOfString:@"[" withString:@""] stringByReplacingOccurrencesOfString:@"]" withString:@""];
    NSArray *components = [componentsString componentsSeparatedByString:@", "];
    return [UIColor colorWithRed:[(NSString*)components[0] floatValue]
                           green:[(NSString*)components[1] floatValue]
                            blue:[(NSString*)components[2] floatValue]
                           alpha:[(NSString*)components[3] floatValue]];
}


@end

The same formatting that is used by NSStringFromCGAffineTransform. This is actually a part of a bigger scale plist object representer in [eppz!kit at GitHub][1].

Best solution I found for this problem is on the following site:

http://arstechnica.com/apple/guides/2009/02/iphone-development-accessing-uicolor-components.ars

After getting the string from a UIColor, it should be an easy enough task to save it to a plist file and retrieve it later on.