Can I reuse colors in Interface Builder? - iphone

Question

I've got several yellow buttons created using Inteface Builder. All have the same color. Currently I declare color in each xib. Can I declared it globally and reuse across all xibs?

Answer 1

Not possible in Interface Builder. Do it in code, for example by creating special subclass of the button.
You could use system Color Palette to save the color, but you still need to apply it to all buttons every time you decide to change it. Or you can just use Recently Used Colors in the color chooser, but neither way is enough dynamic.

Answer 2

Yes, you can do this.
At the bottom of the color picker popup in Interface Builder, there's a row of squares you can use to store colors for later use. Drag a color into it from the rectangle where the current color is shown at the top of the color picker to store it, and then just click a stored color later to use it.

Answer 3

I don't believe there is a way to do this entirely in interface builder, unfortunately. However, you can come pretty close with a little bit of code. The best way I've found to be able to change colors throughout the app in one go is to subclass the item that you want to color (UILabel, for instance) to set the color upon initialization:
#interface HuedUILabel : UILabel
#end
#implementation HuedUILabel
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self) {
// Initialization code
self.textColor = [AppConfig primaryColor];
}
return self;
}
#end
Then, set the label to have a custom class in IB:
Now, when you want to change the color of all your UILabels, you can do it by changing your one color def AND you don't have to clutter your code with a bunch of appearance assignments.

Answer 4

Most definitely!
Create a singleton object (you can call it OksanaColor, to be cool)...
... or, if you're really lazy, a read-only UIColor property that you can access from your app delegate.

Answer 5

You can also add a category on UIColor, so you can use it same as when you use UIColor. For example in my App I add a new file called ApplicationColors which contains all my app colors.
#interface UIColor (ApplicationColours)
+(UIColor *)savaColor;
#end
Implementation:
#implementation UIColor (ApplicationColours)
+(UIColor *)savaColor
{
return [UIColor colorWithRed:228.0f/255.0f green:86.0f/255.0f blue:86.0f/255.0f alpha:1.0f];
}
#end
Then to use it in my app, I import the ApplicationColours.h and use the same as any other UIColor. i.e:
label.textColor = [UIColor savaColor];

Answer 6

Here's a very simple implementation of a named colors category for UIColor. With this code in your project, UIColor will remember any colors you want to save, and will let you access your own colors or system colors using +colorWithName:
#interface UIColor (namedColors)
+ (UIColor *) colorWithName:(NSString *) name;
+ (void) setColor:(UIColor *) color forName:(NSString *) name;
#end
static NSMutableDictionary *colorStorage;
#implementation UIColor (namedColors)
+ (NSMutableDictionary *) colorStorage
{
if (!colorStorage)
colorStorage = [[NSMutableDictionary alloc] initWithCapacity:10];
return colorStorage;
}
+ (UIColor *) colorWithName:(NSString *) name
{
UIColor *result =[[self colorStorage] valueForKey:name]; // See if we have a color with this name in the colorStorage.
if (result) return result;
SEL selector = NSSelectorFromString(name); // look for a class method whose selector matches the given name, such as "blueColor" or "clearColor".
if ([self respondsToSelector:selector] && (result = [self performSelector:selector]))
if ([result isKindOfClass:[self class]])
return result;
return nil;
}
+ (void) setColor:(UIColor *) color forName:(NSString *) name
{
[[self colorStorage] setValue:color forKey:name];
}
#end