Questions tagged [optional-values]
79 questions
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1 answer
Converting from one nullable type to another nullable type
How can one convert from a nullable instance of class A to nullable instance of class B, while B is subclass of A, I tried this but it crashes:
class A
{
}
class B:A
{
}
A? instance_1=something_maybe_null;
if (instance_1.GetType() ==…
AVEbrahimi
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2 answers
iOS and Swift: Ok to force unwrap tableView.indexPath?
I have a segue from a table view controller to another view controller. Inside the method prepare(for: sender) I need to get the indexPath of the cell that triggered the segue. Is it Ok to force unwrap the index path in this case? After all the…
ehmjaysee
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1 answer
Swift: array check for object at index
I have an data model object with several properties. I have a dynamic array that will sometimes have some but not all of the object properties inside of it.
How do I safely check if the array as anything at it's index
DataModel
class Order{
var…
Lance Samaria
- 17,576
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4 answers
Swift 2.0 fatal error: unexpectedly found nil while unwrapping an Optional value (lldb)
let imgURL:NSURL = NSURL(string: "\(ImageName)")!
at the above line,i'm getting fatal error
fatal error: unexpectedly found nil while unwrapping an Optional value
(lldb)
Code :
let ImageName = obj["image"] as! String
let imgURL:NSURL =…
Sridhar G.K
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6 answers
Why is Optional("Text") - Swift
I just started with Swift. So I created a simple application with a label, button and a text field. When you click the button, the app has to change the label with the text of the text field.
class ViewController: UIViewController {
@IBOutlet…
DaniSDE
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3 answers
Ignore an optional prefix in expression
How can I get a string after a prefix that is optional? Example:
Expression Result
------------------------
[asdf]xxx => xxx
[foo]bar => bar
[]bla => bla
test => test
[...] is the optional part.
Obviously, I need a look-around…
robsch
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3 answers
Concatenating an array to another optional values array with the “+=” operator
I have an array of object :
var fooArray = [Foo]()
If I want to append another array with Foo object i can use the += :
fooArray += anotherFooArray
This one works.
But if i'm making the Foo objects in the array optional :
var fooArray =…
Sylver
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1 answer
Swift - unexpectedly found nil while unwrapping an Optional value - calling variable from delegate
I'm trying to create my first iOS app
I got this error "unexpectedly found nil while unwrapping an Optional value" when I try to access variable from my delegate view controller
I'm trying to get a pressed cell value to be set as label text on my…
StereoNight
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4 answers
Found nil while unwrapping an Optional value (Music Library)
var songList = NSMutableArray()
var player = AVPlayer()
var isSelected = false
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
var songs = MPMediaQuery() //…
Abdou23
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2 answers
Swift Optional Type Syntax
According to Apple's Swift guide, when you have the following Array and the following function to search through an Array:
let namesArray = ["John", "Lisa", "Bill", "Jennifer"]
// Note this function is set-up to return an OPTIONAL Int:
func…
sirab333
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1 answer
Why does this work (not using vs. using optionals)?
Why does alternative1 below work flawlessly?
The macros are bogus of course and for illustration purposes only:
func commonPrefixLength
JanX2
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1 answer
HSQLDB optional IN parameter or default parameter value of stored procedure
how can I set default value for an IN parameter of a stored procedure or
how can I set an IN parameter to optional in a stored procedure
in HSQLDB?
I have already tried all of the solution what I learned in SQL generally
and I have already red…
Kata
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How Do You Cause An Optional Element To Be Absent In C# Code Generated With Svcutil.exe's Default Serializer?
I have a WSDL from a web service server which includes the following in its types:
ALEXintlsos
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How do I enable google sheets value bubbles when highlighting portions of formulas
When I would create a formulas like =IF(A2=B2,"yes","no") and I highlighted the A2, it would create a little comment bubble above the highlighted text that gave the value that was in A2. And if I selected A2=B2 it would give me a comment bubble…
0
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0 answers
Paginated Report Matrix Fill Value if Blank from another column
I have the below matrix in the paginated report, if a cell is blank I want to fill the value from the column "All". Any idea?
Image
From the above example for the first row, all blank cells should be filled with a value from "All" column (49).
