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?
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
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
}
其他回答
在故事板和图像资产中。你也可以改变这两个:
更新渲染模式为模板图像
更新视图中的色调颜色。
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];
}
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
}
这是我的UIImage扩展,你可以直接使用changeTintColor函数的图像。
extension UIImage {
func changeTintColor(color: UIColor) -> UIImage {
var newImage = self.withRenderingMode(.alwaysTemplate)
UIGraphicsBeginImageContextWithOptions(self.size, false, newImage.scale)
color.set()
newImage.draw(in: CGRect(x: 0.0, y: 0.0, width: self.size.width, height: self.size.height))
newImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return newImage
}
func changeColor(color: UIColor) -> UIImage {
let backgroundSize = self.size
UIGraphicsBeginImageContext(backgroundSize)
guard let context = UIGraphicsGetCurrentContext() else {
return self
}
var backgroundRect = CGRect()
backgroundRect.size = backgroundSize
backgroundRect.origin.x = 0
backgroundRect.origin.y = 0
var red: CGFloat = 0
var green: CGFloat = 0
var blue: CGFloat = 0
var alpha: CGFloat = 0
color.getRed(&red, green: &green, blue: &blue, alpha: &alpha)
context.setFillColor(red: red, green: green, blue: blue, alpha: alpha)
context.translateBy(x: 0, y: backgroundSize.height)
context.scaleBy(x: 1.0, y: -1.0)
context.clip(to: CGRect(x: 0.0, y: 0.0, width: self.size.width, height: self.size.height),
mask: self.cgImage!)
context.fill(backgroundRect)
var imageRect = CGRect()
imageRect.size = self.size
imageRect.origin.x = (backgroundSize.width - self.size.width) / 2
imageRect.origin.y = (backgroundSize.height - self.size.height) / 2
context.setBlendMode(.multiply)
context.draw(self.cgImage!, in: imageRect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage!
}
}
示例用法如下
let image = UIImage(named: "sample_image")
imageView.image = image.changeTintColor(color: UIColor.red)
你可以使用change changeColor函数来改变图像的颜色
另外,对于以上的答案,在iOS 13及以后有一个干净的方法
let image = UIImage(named: "imageName")?.withTintColor(.white, renderingMode: .alwaysTemplate)