UILabel textColor property marked as nonnull, but comment as nil by default
In the Apple class of UILabel
open class UILabel : UIView, NSCoding, UIContentSizeCategoryAdjusting {
open var text: String? // default is nil
open var font: UIFont! // default is nil (system font 17 plain)
open var textColor: UIColor! // default is nil (text draws black)
but what totaly confuses me, is that font and textColor are marked as ! so they cannot be nil (or else crash), but the comment states
default is nil
am i missing smth. or not understand smth. proper, or is this some documentation fault or the var is assigned wrong with ! and should have had ?
swift uilabel
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
add a comment |
In the Apple class of UILabel
open class UILabel : UIView, NSCoding, UIContentSizeCategoryAdjusting {
open var text: String? // default is nil
open var font: UIFont! // default is nil (system font 17 plain)
open var textColor: UIColor! // default is nil (text draws black)
but what totaly confuses me, is that font and textColor are marked as ! so they cannot be nil (or else crash), but the comment states
default is nil
am i missing smth. or not understand smth. proper, or is this some documentation fault or the var is assigned wrong with ! and should have had ?
swift uilabel
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
add a comment |
In the Apple class of UILabel
open class UILabel : UIView, NSCoding, UIContentSizeCategoryAdjusting {
open var text: String? // default is nil
open var font: UIFont! // default is nil (system font 17 plain)
open var textColor: UIColor! // default is nil (text draws black)
but what totaly confuses me, is that font and textColor are marked as ! so they cannot be nil (or else crash), but the comment states
default is nil
am i missing smth. or not understand smth. proper, or is this some documentation fault or the var is assigned wrong with ! and should have had ?
swift uilabel
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
In the Apple class of UILabel
open class UILabel : UIView, NSCoding, UIContentSizeCategoryAdjusting {
open var text: String? // default is nil
open var font: UIFont! // default is nil (system font 17 plain)
open var textColor: UIColor! // default is nil (text draws black)
but what totaly confuses me, is that font and textColor are marked as ! so they cannot be nil (or else crash), but the comment states
default is nil
am i missing smth. or not understand smth. proper, or is this some documentation fault or the var is assigned wrong with ! and should have had ?
swift uilabel
swift uilabel
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
asked Nov 21 '18 at 18:11
Peter LapisuPeter Lapisu
12.4k1193147
12.4k1193147
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
Try this in playground
import UIKit
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 45)
print(label.font)
label.font = nil
print(label.font)
This will be result:
Optional(<UICTFont: 0x7ff122c059d0> font-family: ".SFUIDisplay"; font-weight: normal; font-style: normal; font-size: 45.00pt)
Optional(<UICTFont: 0x7ff122e04390> font-family: ".SFUIText"; font-weight: normal; font-style: normal; font-size: 17.00pt)
Optional seems and in my humble opinion is only the tool for setting the default value. Imagine scenario when it is not an optional. There would be no easy way to set it back. If it would be in Swift I bet it would look something like this:
class Label {
var font: UIFont! = nil {
//Set some default font in here
didSet { if font == nil { font = UIFont.systemFont(ofSize: 17)} }
}
}
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Try this in playground
import UIKit
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 45)
print(label.font)
label.font = nil
print(label.font)
This will be result:
Optional(<UICTFont: 0x7ff122c059d0> font-family: ".SFUIDisplay"; font-weight: normal; font-style: normal; font-size: 45.00pt)
Optional(<UICTFont: 0x7ff122e04390> font-family: ".SFUIText"; font-weight: normal; font-style: normal; font-size: 17.00pt)
Optional seems and in my humble opinion is only the tool for setting the default value. Imagine scenario when it is not an optional. There would be no easy way to set it back. If it would be in Swift I bet it would look something like this:
class Label {
var font: UIFont! = nil {
//Set some default font in here
didSet { if font == nil { font = UIFont.systemFont(ofSize: 17)} }
}
}
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
add a comment |
Try this in playground
import UIKit
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 45)
print(label.font)
label.font = nil
print(label.font)
This will be result:
Optional(<UICTFont: 0x7ff122c059d0> font-family: ".SFUIDisplay"; font-weight: normal; font-style: normal; font-size: 45.00pt)
Optional(<UICTFont: 0x7ff122e04390> font-family: ".SFUIText"; font-weight: normal; font-style: normal; font-size: 17.00pt)
Optional seems and in my humble opinion is only the tool for setting the default value. Imagine scenario when it is not an optional. There would be no easy way to set it back. If it would be in Swift I bet it would look something like this:
class Label {
var font: UIFont! = nil {
//Set some default font in here
didSet { if font == nil { font = UIFont.systemFont(ofSize: 17)} }
}
}
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
add a comment |
Try this in playground
import UIKit
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 45)
print(label.font)
label.font = nil
print(label.font)
This will be result:
Optional(<UICTFont: 0x7ff122c059d0> font-family: ".SFUIDisplay"; font-weight: normal; font-style: normal; font-size: 45.00pt)
Optional(<UICTFont: 0x7ff122e04390> font-family: ".SFUIText"; font-weight: normal; font-style: normal; font-size: 17.00pt)
Optional seems and in my humble opinion is only the tool for setting the default value. Imagine scenario when it is not an optional. There would be no easy way to set it back. If it would be in Swift I bet it would look something like this:
class Label {
var font: UIFont! = nil {
//Set some default font in here
didSet { if font == nil { font = UIFont.systemFont(ofSize: 17)} }
}
}
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
Try this in playground
import UIKit
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 45)
print(label.font)
label.font = nil
print(label.font)
This will be result:
Optional(<UICTFont: 0x7ff122c059d0> font-family: ".SFUIDisplay"; font-weight: normal; font-style: normal; font-size: 45.00pt)
Optional(<UICTFont: 0x7ff122e04390> font-family: ".SFUIText"; font-weight: normal; font-style: normal; font-size: 17.00pt)
Optional seems and in my humble opinion is only the tool for setting the default value. Imagine scenario when it is not an optional. There would be no easy way to set it back. If it would be in Swift I bet it would look something like this:
class Label {
var font: UIFont! = nil {
//Set some default font in here
didSet { if font == nil { font = UIFont.systemFont(ofSize: 17)} }
}
}
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
answered Nov 21 '18 at 18:44
LuzoLuzo
1,025614
1,025614
add a comment |
add a comment |
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