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

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]];

其他回答

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
    }
}

斯威夫特5

重绘图像的背景和填充颜色

extension UIImage {
  func withBackground(color: UIColor, fill fillColor: UIColor) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(size, true, scale)
    
    guard let ctx = UIGraphicsGetCurrentContext(), let image = cgImage else { return self }
    defer { UIGraphicsEndImageContext() }
    
    ctx.concatenate(CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: size.height))
    
    let rect = CGRect(origin: .zero, size: size)
    
    // draw background
    ctx.setFillColor(color.cgColor)
    ctx.fill(rect)
    
    // draw image with fill color
    ctx.clip(to: rect, mask: image)
    ctx.setFillColor(fillColor.cgColor)
    ctx.fill(rect)
    
    return UIGraphicsGetImageFromCurrentImageContext() ?? self
  }
}

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

用于着色UIButton的图像

let image1 = "ic_shopping_cart_empty"
btn_Basket.setImage(UIImage(named: image1)?.withRenderingMode(.alwaysTemplate), for: .normal)
btn_Basket.setImage(UIImage(named: image1)?.withRenderingMode(.alwaysTemplate), for: .selected)
btn_Basket.imageView?.tintColor = UIColor(UIColor.Red)

试试这个

http://robots.thoughtbot.com/designing-for-ios-blending-modes

or

- (void)viewDidLoad
{
[super viewDidLoad];

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(10, 30, 300, 50)];
label.numberOfLines = 0;
label.font = [UIFont systemFontOfSize:13];
label.text = @"These checkmarks use the same gray checkmark image with a tintColor applied to the image view";
[self.view addSubview:label];

[self _createImageViewAtY:100 color:[UIColor purpleColor]];
}

- (void)_createImageViewAtY:(int)y color:(UIColor *)color {
UIImage *image = [[UIImage imageNamed:@"gray checkmark.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
CGRect frame = imageView.frame;
frame.origin.x = 100;
frame.origin.y = y;
imageView.frame = frame;

if (color)
    imageView.tintColor = color;

[self.view addSubview:imageView];
}