Each (default) tab bar item consists of text and icon. It is pretty easy to change the text colors globally by specifying the appearance:
// you can add this code to you AppDelegate application:didFinishLaunchingWithOptions:
// or add it to viewDidLoad method of your TabBarController class
UITabBarItem.appearance().setTitleTextAttributes([NSForegroundColorAttributeName: UIColor.magentaColor()], forState:.Normal)
UITabBarItem.appearance().setTitleTextAttributes([NSForegroundColorAttributeName: UIColor.redColor()], forState:.Selected)
With images situation is a little bit more complicated. You cannot define their appearance globally. You should redefine them in your TabBarController class. Add code bellow to viewDidLoad
method of your TabBarController
class:
for item in self.tabBar.items as [UITabBarItem] {
if let image = item.image {
item.image = image.imageWithColor(UIColor.yellowColor()).imageWithRenderingMode(.AlwaysOriginal)
}
}
As we know there is no imageWithColor(...)
method in UIImage class. So here is the extension implementation:
// Add anywhere in your app
extension UIImage {
func imageWithColor(tintColor: UIColor) -> UIImage {
UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
let context = UIGraphicsGetCurrentContext() as CGContextRef
CGContextTranslateCTM(context, 0, self.size.height)
CGContextScaleCTM(context, 1.0, -1.0);
CGContextSetBlendMode(context, .Normal)
let rect = CGRectMake(0, 0, self.size.width, self.size.height) as CGRect
CGContextClipToMask(context, rect, self.CGImage)
tintColor.setFill()
CGContextFillRect(context, rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext() as UIImage
UIGraphicsEndImageContext()
return newImage
}
}
imageWithColor
was borrowed from this answer: https://stackoverflow.com/a/24545102/3050466
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