I noticed that when I place a white or black UIImage into a UISegmentedControl it automatically color masks it to match the tint of the segmented control. I thought this was really cool, and was wondering if I could do this elsewhere as well. For example, I have a bunch of buttons that have a uniform shape but varied colors. Instead of making a PNG for each button, could I somehow use this color masking to use the same image for all of them but then set a tint color or something to change their actual color?


当前回答

在Swift中,你可以这样做:

var exampleImage = UIImage(named: "ExampleImage.png")?.imageWithRenderingMode(.AlwaysTemplate)

然后在viewDidLoad中

exampleButtonOutlet.setImage(exampleImage, forState: UIControlState.Normal)

并修改颜色

exampleButtonOutlet.tintColor = UIColor(red: 1, green: 0, blue: 0, alpha: 1) //your color

编辑Xcode 8 现在你也可以在你的.xcassets to Template image中设置图像的呈现模式,然后你就不需要在var exampleImage中特别声明它了

其他回答

为了在按钮上设置白色的图像(箭头图标),我们使用:

let imageOnButton = UIImage(named: "navForwardArrow")?.imageWithColor(color: UIColor.white)
button.setImage(imageOnButton, for: .normal)

已知问题:当按下按钮时,图标会失去白色。

截图:

你应该试试

设置好框架后

NSArray *arr10 =[NSArray arrayWithObjects:btn1,btn2,nil];
for(UIButton *btn10 in arr10)
{
CAGradientLayer *btnGradient2 = [CAGradientLayer layer];
btnGradient2.frame = btn10.bounds;

btnGradient2.colors = [NSArray arrayWithObjects:
                       (id)[[UIColor colorWithRed:151.0/255.0f green:206.0/255.5 blue:99.0/255.0 alpha:1] CGColor],
                       (id)[[UIColor colorWithRed:126.0/255.0f green:192.0/255.5 blue:65.0/255.0 alpha:1]CGColor],
                       nil];
[btn10.layer insertSublayer:btnGradient2 atIndex:0];

}

改变按钮图像或图像视图色调颜色

btn.imageView?.image = btn.imageView?.image?.withRenderingMode(.alwaysTemplate)

btn.imageView?.tintColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 1)

不确定你到底想要什么,但这个category方法会用指定的颜色掩盖一个UIImage,所以你可以有一个单独的图像,改变它的颜色为任何你想要的。

ImageUtils.h

- (UIImage *) maskWithColor:(UIColor *)color;

ImageUtils.m

-(UIImage *) maskWithColor:(UIColor *)color 
{
    CGImageRef maskImage = self.CGImage;
    CGFloat width = self.size.width;
    CGFloat height = self.size.height;
    CGRect bounds = CGRectMake(0,0,width,height);

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef bitmapContext = CGBitmapContextCreate(NULL, width, height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast);
    CGContextClipToMask(bitmapContext, bounds, maskImage);
    CGContextSetFillColorWithColor(bitmapContext, color.CGColor);    
    CGContextFillRect(bitmapContext, bounds);

    CGImageRef cImage = CGBitmapContextCreateImage(bitmapContext);
    UIImage *coloredImage = [UIImage imageWithCGImage:cImage];

    CGContextRelease(bitmapContext);
    CGColorSpaceRelease(colorSpace);
    CGImageRelease(cImage);

    return coloredImage;    
}

导入ImageUtils类别并执行如下操作…

#import "ImageUtils.h"

...

UIImage *icon = [UIImage imageNamed:ICON_IMAGE];

UIImage *redIcon = [icon maskWithColor:UIColor.redColor];
UIImage *blueIcon = [icon maskWithColor:UIColor.blueColor];
let button = UIButton(type: .custom)
let image = UIImage(named: "image_name")?.withRenderingMode(.alwaysTemplate)
button.setImage(image, for: .normal)
button.tintColor = UIColor.red

如果你在设置UIButton。tintColor by UIColor(r:g:b:alpha:),记住值除以255。这些RGB值应该在0和1之间。