我有一个名为theImageView的UIImageView, UIImage是单色的(透明背景),就像下面左边的黑色心形。我如何在iOS 7或更高的系统中,根据iOS 7+导航栏图标中使用的色调方法,以编程方式更改此图像的色调颜色?

这个方法也适用于WatchKit的Apple Watch应用程序吗?


当前回答

如果有人关心没有UIImageView的解决方案:

// (Swift 3)
extension UIImage {
    func tint(with color: UIColor) -> UIImage {
        var image = withRenderingMode(.alwaysTemplate)
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        color.set()

        image.draw(in: CGRect(origin: .zero, size: size))
        image = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return image
    }
}

其他回答

这里有一个类别应该可以做到这一点

@interface UIImage(Overlay)
@end

@implementation UIImage(Overlay)

- (UIImage *)imageWithColor:(UIColor *)color1
{
        UIGraphicsBeginImageContextWithOptions(self.size, NO, self.scale);
        CGContextRef context = UIGraphicsGetCurrentContext();
        CGContextTranslateCTM(context, 0, self.size.height);
        CGContextScaleCTM(context, 1.0, -1.0);
        CGContextSetBlendMode(context, kCGBlendModeNormal);
        CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
        CGContextClipToMask(context, rect, self.CGImage);
        [color1 setFill];
        CGContextFillRect(context, rect);
        UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        return newImage;
}
@end

所以你会这样做:

theImageView.image = [theImageView.image imageWithColor:[UIColor redColor]];

这是一个简单的扩展,适用于Swift 5:

extension UIImageView {

func setImageTintColor(_ color: UIColor) {
    let tintedImage = self.image?.withRenderingMode(.alwaysTemplate)
    self.image = tintedImage
    self.tintColor = color
  }
}

用法:

myImageView.setImageTintColor(.systemBlue)

子类,也可以从代码和接口生成器中使用:

@implementation TintedImageView

- (instancetype)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (self) {
        [self setup];
    }
    return self;
}

- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    self = [super initWithCoder:aDecoder];
    if (self) {
        [self setup];
    }
    return self;
}

-(void)setup {
    self.image = [self.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
}

@end

iOS

解决方案从接口生成器,设置templateImage参数在keyPath和选择您的色调颜色从IB

extension UIImageView {

// make template image with tint color
var templateImage: Bool {
    set {
        if newValue, let image = self.image {
            let newImage = image.withRenderingMode(.alwaysTemplate)
            self.image = newImage
        }
    } get {
        return false
    }
}

}

Swift 3版本的扩展答案从模糊

func imageWithColor(color: UIColor) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
    color.setFill()

    let context = UIGraphicsGetCurrentContext()! as CGContext
    context.translateBy(x: 0, y: self.size.height)
    context.scaleBy(x: 1.0, y: -1.0);
    context.setBlendMode(.normal)

    let rect = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height) as CGRect
    context.clip(to: rect, mask: self.cgImage!)
    context.fill(rect)

    let newImage = UIGraphicsGetImageFromCurrentImageContext()! as UIImage
    UIGraphicsEndImageContext()

    return newImage
}