UIView's border color in Interface builder doe

Question

I am trying to set up a view's layer properties via IB. Everything works except for color of the border (property layer.borderColor):

I remember running into this problem a year ago and I ended up doing it programatically. And still, I can do this programmatically, but I am curious why the layer.borderColorproperty never works via interface builder. I don't want to import QuartzCore, and then write extra line of code just because of this, seems like an overkill.

Answer 1

You can set a value for the "borderColor" key in the XIB and use:

extension UIView {

    open override func setValue(_ value: Any?, forKey key: String) {
        guard key == "borderColor", let color = value as? UIColor else {
            super.setValue(value, forKey: key)
            return
        }

        layer.borderColor = color.cgColor
    }
}

Answer 2

Here's a quick way to overcome this. Categories...

@interface UIView (IBAppearance)

@property (nonatomic, strong) UIColor *borderColor;

@end

You don't have to store it, it's just nice so you can query later. The important thing is taking the value and assigning the UIColor's CGColor to the layer.

#import <objc/runtime.h>

#define BORDER_COLOR_KEYPATH @"borderColor"

@implementation UIView (IBAppearance)

- (void)setBorderColor:(UIColor *)borderColor {
    UIColor *bc = objc_getAssociatedObject(self, BORDER_COLOR_KEYPATH);
    if(bc == borderColor) return;
    else {
        objc_setAssociatedObject(self, BORDER_COLOR_KEYPATH, borderColor, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
        self.layer.borderColor = [borderColor CGColor];
    }
}

- (UIColor *)borderColor {
    return objc_getAssociatedObject(self, BORDER_COLOR_KEYPATH);
}

@end

Of course, in the Interface Builder you're not setting the value on layer.borderColor, rather just on borderColor.

Answer 3

You can customise border with 2 methods. First one is this. Just click on the object go to the identity inspector and set the attributes.

Second one is this. make an IBOutlet of required object and put this code in view did load.

@IBOutlet weak var uploadView: UIView!

    override func viewDidLoad() {
        super.viewDidLoad()

        uploadView.layer.cornerRadius = 10
        uploadView.layer.borderWidth = 1.0
        uploadView.layer.borderColor = #colorLiteral(red: 0.08235294118, green: 0.5058823529, blue: 0.9450980392, alpha: 1)
    }

Answer 4

Use IBDesignable instead of Runtime Attributes it is more clear.

Put this code in any class and edit the properties direct on the storyboard.

import UIKit

@IBDesignable extension UIView {
    @IBInspectable var borderColor:UIColor? {
        set {
            layer.borderColor = newValue!.CGColor
        }
        get {
            if let color = layer.borderColor {
                return UIColor(CGColor:color)
            }
            else {
                return nil
            }
        }
    }
    @IBInspectable var borderWidth:CGFloat {
        set {
            layer.borderWidth = newValue
        }
        get {
            return layer.borderWidth
        }
    }
    @IBInspectable var cornerRadius:CGFloat {
        set {
            layer.cornerRadius = newValue
            clipsToBounds = newValue > 0
        }
        get {
            return layer.cornerRadius
        }
    }
}

Answer 5

You have to create Category for CALayer:

CALayer+UIColor.h

#import <QuartzCore/QuartzCore.h>
#import <UIKit/UIKit.h>

@interface CALayer(UIColor)

// This assigns a CGColor to borderColor.
@property(nonatomic, assign) UIColor* borderUIColor;

@end

CALayer+UIColor.m

#import "CALayer+UIColor.h"

@implementation CALayer(UIColor)

- (void)setBorderUIColor:(UIColor*)color {
    self.borderColor = color.CGColor;
}

- (UIColor*)borderUIColor {
    return [UIColor colorWithCGColor:self.borderColor];
}

@end

And then in User Defined Runtime attributes You can use it as it is on image below:

For Swift it is much more simple:

@IBInspectable var borderColor: UIColor? {
    didSet {
        layer.borderColor = borderColor?.CGColor
        layer.borderWidth = 1
    }
}

Then in Xcode you can use it like this:

Once you choose sth it is automatically added to your runtime attributes:

Answer 6

It's possible to do this, but it's not a built-in feature. This is because the Color type in the User Defined Runtime Attributes panel creates a UIColor, but layer.borderColor holds a CGColorRef type. Unfortunately, there's no way to assign a CGColorRef type in Interface Builder.

However, this is possible through a proxy property. See Peter DeWeese's answer to a different question for a possible solution to this problem. His answer defines a category that allows a proxy color to be set through Interface Builder.