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

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

其他回答

iOS 对于iOS应用程序,在Swift 3,4或5中:

theImageView.image = theImageView.image?.withRenderingMode(.alwaysTemplate)
theImageView.tintColor = UIColor.red

对于Swift 2:

theImageView.image = theImageView.image?.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate)
theImageView.tintColor = UIColor.redColor()

同时,现代的Objective-C解决方案是:

theImageView.image = [theImageView.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[theImageView setTintColor:[UIColor redColor]];

Watchkit 在Apple Watch应用程序的WatchKit中,您可以为模板图像设置色调颜色。

您必须将图像添加到WatchKit应用程序中的资产目录,并将图像集设置为在属性检查器中呈现为模板图像。与iPhone应用程序不同,您目前不能在WatchKit扩展的代码中设置模板渲染。 设置该图像用于你的WKInterfaceImage在界面生成器为你的应用程序 创建一个IBOutlet在你的WKInterfaceController为WKInterfaceImage称为“theImage”…

然后在Swift 3或4中设置色调颜色:

theImage.setTintColor(UIColor.red)

斯威夫特2:

theImage.setTintColor(UIColor.redColor())

然后在Objective-C中设置色调颜色:

[self.theImage setTintColor:[UIColor redColor]];

如果您使用模板图像并且没有应用着色颜色,则将应用WatchKit应用程序的全局着色。如果你没有设置全局色调,当作为模板图像使用时,图像将默认为浅蓝色。

与迅速

let commentImageView = UIImageView(frame: CGRectMake(100, 100, 100, 100))
commentImageView.image = UIImage(named: "myimage.png")!.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate)
commentImageView.tintColor = UIColor.blackColor()
addSubview(commentImageView)

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]];

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
}

你可以在Swift 3中使用它,如果你有一个图像来替换清除按钮

func addTextfieldRightView(){

    let rightViewWidth:CGFloat = 30

    let viewMax = self.searchTxt.frame.height
    let buttonMax = self.searchTxt.frame.height - 16

    let buttonView = UIView(frame: CGRect(
        x: self.searchTxt.frame.width - rightViewWidth,
        y: 0,
        width: viewMax,
        height: viewMax))

    let myButton = UIButton(frame: CGRect(
        x: (viewMax - buttonMax) / 2,
        y: (viewMax - buttonMax) / 2,
        width: buttonMax,
        height: buttonMax))

    myButton.setImage(UIImage(named: "BlueClear")!, for: .normal)

    buttonView.addSubview(myButton)

    let clearPressed = UITapGestureRecognizer(target: self, action: #selector(SearchVC.clearPressed(sender:)))
    buttonView.isUserInteractionEnabled = true
    buttonView.addGestureRecognizer(clearPressed)

    myButton.addTarget(self, action: #selector(SearchVC.clearPressed(sender:)), for: .touchUpInside)

    self.searchTxt.rightView = buttonView
    self.searchTxt.rightViewMode = .whileEditing
}