Question

我正在开发一个应用程序，其中元素需要以不同的颜色进行自定义。到目前为止，我一直在利用tintColor和imageWithRenderingMode来更改图片颜色。我目前处于需要使用UIColor(patternImage:)和backgroundColor添加背景图块图像的情况。有没有办法将一种色调应用于背景图块图像，以便我可以在运行时更改背景图像颜色？

Answer 1

您可以将TintColor应用于UIImage并使用该UIImage作为平铺的背景颜色。

将tintColor应用于UIImage：

- (UIImage *) addOverlaytoImage:(UIImage *)mySourceImage
{
    UIImage * image = mySourceImage;
    UIColor * color = [UIColor yellowColor];
    UIGraphicsBeginImageContext(image.size);
    [image drawInRect:CGRectMake(0, 0, image.size.width, image.size.height) blendMode:kCGBlendModeNormal alpha:1];
    UIBezierPath * path = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, image.size.width, image.size.height)];
    [color setFill];
    [path fillWithBlendMode:kCGBlendModeMultiply alpha:1]; //look up blending modes for your needs
    UIImage * newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return newImage;
}

然后将此图像添加到背景颜色参数：

yourView.backgroundColor = [UIColor colorWithPatternImage:[self addOverlaytoImage:myImage]];

请参阅以下链接：Designing for iOS: Blending Modes

Answer 2

通过我找到here的链接，这就是我的工作原理

// originalImage and originalColor are defined
var image = originalImage.imageWithRenderingMode(.AlwaysTemplate)
UIGraphicsBeginImageContextWithOptions(
    originalImage.size,
    false,
    originalImage.scale)
originalColor.set()
image.drawInRect(CGRectMake(
    0,
    0,
    originalImage.size.width,
    originalImage.size.height))
image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return UIColor(patternImage: image)

Answer 3

J_P，谢谢您的回答！真的很有帮助。我只想发布Swift 5的更新版本

extension UIColor {
    convenience init(patternImage: UIImage, tintColor: UIColor) {
        var image = patternImage.withRenderingMode(.alwaysTemplate)
        UIGraphicsBeginImageContextWithOptions(patternImage.size,
                                               false,
                                               patternImage.scale)
        tintColor.set()   
        image.draw(in: CGRect(x: 0, y: 0,
                              width: patternImage.size.width,
                              height: patternImage.size.height))
        image = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        self.init(patternImage: image)
    }
}

UIColor图案图像和色调

3 个答案: