Accessing properties via interface builder is quite easy and more developer friendly.

Here I’m guiding you how to to add new/custom properties to interface builder.

1- Subclass any UIObject, we are considering here UIButton for now, as shown below:
 

class YourCustomButton: UIButton {

}

2- Add properties that you want to be visible in interface builder attribute inspector for the object.

class YourCustomButton: UIButton {
    
   	@IBInspectable var buttonCornerRadius:CGFloat{
        
      	set{
		    self.layer.cornerRadius = newValue // Setting corner radius of button; newValue is changed value.
        }
        get{
            return self.layer.cornerRadius		// returning corner radius of button
        }
    } 
}

We have added buttonCornerRadius as a new property having getter and setter. Using this property we are setting corner radius of Button

3- Now in interface Builder change the class of UIButton to TDCustomButton.

4- Once you are done with changing the button class, “buttonCornerRadius” property will start appearing on the attribute inspector.

5- Now you can change the corner radius directly from interface builder attribute inspector.

If you want to get result at build time then use “@IBDesignable” before “class” as below:

@IBDesignable class YourCustomButton: UIButton {
    
}

using @IBDesignable will show the changes immediately while changing values in interface builder.